TY  - JOUR
AU  - Homšek, Ana
AU  - Marković, Bojan
AU  - Bogavac-Stanojević, Nataša
AU  - Vladimirov, Sote
AU  - Karljiković-Rajić, Katarina
PY  - 2020
UR  - https://farfar.pharmacy.bg.ac.rs/handle/123456789/4833
AB  - The application assessment of different programs was performed with equivalence tests for method transfer pro second-order derivative spectrophotometry. The digital second-order derivative spectra were calculated on different instruments; GBC Scientific Equipment Cintra 20 (Cintral v.2.6 and Spectral v.1.70 software programs) and Thermo Scientific Evolution 300 (VISIONPro software) were analyzed using the amplitude A/B ratio (A = 2D265,263; B = 2D263,261). Amplitude A/B ratio is the resolution parameter for derivative spectrophotometry prescribed in European Pharmacopoeia. The obtained values for A/B ratio were either very similar or significantly different among programs: 0.669 (Cintral v.2.6), 0.549 (Spectral v.1.70), 0.556 (medium indirect VISIONPro), 0.557 (one-step Savitzky–Golay 7 VISIONPro), 0.689 (two-step Savitzky–Golay 7 VISIONPro). Method transfer was possible between Spectral v.1.70 and VISIONPro (medium indirect and one-step Savitzky–Golay 7), but the values obtained in Cintral v.2.6 were not comparable to the other programs. The absorbance data exported from both instruments were additionally calculated in OriginPro8 which provided almost the same mean A/B values (0.627 Cintral v.2.6; 0.624 VISIONPro), confirming that the two instruments recorded the same zero-order spectra. The calculation of resolution parameter could be used for verification of program comparison, which would enable transfer between sender and receiver laboratory. The accordance between program algorithms was confirmed when acceptable differences for values of resolution parameter (A/B ratios) were achieved.
PB  - SAGE Publications
T2  - Applied Spectroscopy
T1  - Method Transfer Evaluation for Digital Derivative Spectrophotometry Through its Resolution Parameter Comparison of Different Computer Programs
VL  - 74
IS  - 5
SP  - 525
EP  - 535
DO  - 10.1177/0003702819889374
ER  - 

@article{
author = "Homšek, Ana and Marković, Bojan and Bogavac-Stanojević, Nataša and Vladimirov, Sote and Karljiković-Rajić, Katarina",
year = "2020",
abstract = "The application assessment of different programs was performed with equivalence tests for method transfer pro second-order derivative spectrophotometry. The digital second-order derivative spectra were calculated on different instruments; GBC Scientific Equipment Cintra 20 (Cintral v.2.6 and Spectral v.1.70 software programs) and Thermo Scientific Evolution 300 (VISIONPro software) were analyzed using the amplitude A/B ratio (A = 2D265,263; B = 2D263,261). Amplitude A/B ratio is the resolution parameter for derivative spectrophotometry prescribed in European Pharmacopoeia. The obtained values for A/B ratio were either very similar or significantly different among programs: 0.669 (Cintral v.2.6), 0.549 (Spectral v.1.70), 0.556 (medium indirect VISIONPro), 0.557 (one-step Savitzky–Golay 7 VISIONPro), 0.689 (two-step Savitzky–Golay 7 VISIONPro). Method transfer was possible between Spectral v.1.70 and VISIONPro (medium indirect and one-step Savitzky–Golay 7), but the values obtained in Cintral v.2.6 were not comparable to the other programs. The absorbance data exported from both instruments were additionally calculated in OriginPro8 which provided almost the same mean A/B values (0.627 Cintral v.2.6; 0.624 VISIONPro), confirming that the two instruments recorded the same zero-order spectra. The calculation of resolution parameter could be used for verification of program comparison, which would enable transfer between sender and receiver laboratory. The accordance between program algorithms was confirmed when acceptable differences for values of resolution parameter (A/B ratios) were achieved.",
publisher = "SAGE Publications",
journal = "Applied Spectroscopy",
title = "Method Transfer Evaluation for Digital Derivative Spectrophotometry Through its Resolution Parameter Comparison of Different Computer Programs",
volume = "74",
number = "5",
pages = "525-535",
doi = "10.1177/0003702819889374"
}

Homšek, A., Marković, B., Bogavac-Stanojević, N., Vladimirov, S.,& Karljiković-Rajić, K.. (2020). Method Transfer Evaluation for Digital Derivative Spectrophotometry Through its Resolution Parameter Comparison of Different Computer Programs. in Applied Spectroscopy
SAGE Publications., 74(5), 525-535.
https://doi.org/10.1177/0003702819889374

Homšek A, Marković B, Bogavac-Stanojević N, Vladimirov S, Karljiković-Rajić K. Method Transfer Evaluation for Digital Derivative Spectrophotometry Through its Resolution Parameter Comparison of Different Computer Programs. in Applied Spectroscopy. 2020;74(5):525-535.
doi:10.1177/0003702819889374 .

Homšek, Ana, Marković, Bojan, Bogavac-Stanojević, Nataša, Vladimirov, Sote, Karljiković-Rajić, Katarina, "Method Transfer Evaluation for Digital Derivative Spectrophotometry Through its Resolution Parameter Comparison of Different Computer Programs" in Applied Spectroscopy, 74, no. 5 (2020):525-535,
https://doi.org/10.1177/0003702819889374 . .

TY  - JOUR
AU  - Radulović, Valentina
AU  - Ivković, Branka
AU  - Bogavac-Stanojević, Nataša
AU  - Karljiković-Rajić, Katarina
PY  - 2020
UR  - https://farfar.pharmacy.bg.ac.rs/handle/123456789/3708
AB  - The background of this study was transfer assessment for H3BO3 assays according to different pharmacopoeias’ monographs and verification of the crucial parameters—the polyols’ excess (mannitol, glycerine, sorbitol), the initial H3BO3 concentrations and the indicator’s concentrations. The purpose of the work was the comparative study according to different pharmacopoeias: the European (EP 9), the American (USP 35-NF 30), the Japanese (JP XVII), important for quality control of H3BO3, as an active component or an excipient. pH analyses were set up to establish the effects of selected polyols and the initial H3BO3 concentrations. For evaluation of assay results and methods’ equivalence, standard t test and two one-sided t test (TOST) were applied. Pharmacopoeias’ procedures propose volumetric analyses by 1 M NaOH standard solution with visual end-point detection (phenolphthalein) using sufficiently high H3BO3 concentrations and less excess of polyols, as the good alternative to potentiometric method. The influence of phenolphthalein’s concentration (0.1%, 1%), evidenced as relevant factor, caused the difference shown by standard t test: 99.82% (EP 9) and 99.66% (JP XVII). Equivalences between three methods were confirmed by TOST procedures with defined acceptance criterion ± 2% derived from the mean value (99.83%). The comparative study results pointed out that the initial phenolphthalein’s concentration was the crucial influencing factor on harmonization of assay mean values, which was confirmed by TOST application for the methods’ equivalency in method transfer evaluation. The best possible correlation between the lowest excess of polyol-sorbitol and the highest initial boric acid concentration was proved by JP XVII, which was indicated by pH-metric analyses. Graphic abstract: [Figure not available: see fulltext.]
PB  - Springer  Nature
T2  - Chemical Papers
T1  - Method transfer assessment for boric acid assays according to different pharmacopoeias' monographs
DO  - 10.1007/s11696-020-01377-x
ER  - 

@article{
author = "Radulović, Valentina and Ivković, Branka and Bogavac-Stanojević, Nataša and Karljiković-Rajić, Katarina",
year = "2020",
abstract = "The background of this study was transfer assessment for H3BO3 assays according to different pharmacopoeias’ monographs and verification of the crucial parameters—the polyols’ excess (mannitol, glycerine, sorbitol), the initial H3BO3 concentrations and the indicator’s concentrations. The purpose of the work was the comparative study according to different pharmacopoeias: the European (EP 9), the American (USP 35-NF 30), the Japanese (JP XVII), important for quality control of H3BO3, as an active component or an excipient. pH analyses were set up to establish the effects of selected polyols and the initial H3BO3 concentrations. For evaluation of assay results and methods’ equivalence, standard t test and two one-sided t test (TOST) were applied. Pharmacopoeias’ procedures propose volumetric analyses by 1 M NaOH standard solution with visual end-point detection (phenolphthalein) using sufficiently high H3BO3 concentrations and less excess of polyols, as the good alternative to potentiometric method. The influence of phenolphthalein’s concentration (0.1%, 1%), evidenced as relevant factor, caused the difference shown by standard t test: 99.82% (EP 9) and 99.66% (JP XVII). Equivalences between three methods were confirmed by TOST procedures with defined acceptance criterion ± 2% derived from the mean value (99.83%). The comparative study results pointed out that the initial phenolphthalein’s concentration was the crucial influencing factor on harmonization of assay mean values, which was confirmed by TOST application for the methods’ equivalency in method transfer evaluation. The best possible correlation between the lowest excess of polyol-sorbitol and the highest initial boric acid concentration was proved by JP XVII, which was indicated by pH-metric analyses. Graphic abstract: [Figure not available: see fulltext.]",
publisher = "Springer  Nature",
journal = "Chemical Papers",
title = "Method transfer assessment for boric acid assays according to different pharmacopoeias' monographs",
doi = "10.1007/s11696-020-01377-x"
}

Radulović, V., Ivković, B., Bogavac-Stanojević, N.,& Karljiković-Rajić, K.. (2020). Method transfer assessment for boric acid assays according to different pharmacopoeias' monographs. in Chemical Papers
Springer  Nature..
https://doi.org/10.1007/s11696-020-01377-x

Radulović V, Ivković B, Bogavac-Stanojević N, Karljiković-Rajić K. Method transfer assessment for boric acid assays according to different pharmacopoeias' monographs. in Chemical Papers. 2020;.
doi:10.1007/s11696-020-01377-x .

Radulović, Valentina, Ivković, Branka, Bogavac-Stanojević, Nataša, Karljiković-Rajić, Katarina, "Method transfer assessment for boric acid assays according to different pharmacopoeias' monographs" in Chemical Papers (2020),
https://doi.org/10.1007/s11696-020-01377-x . .

TY  - JOUR
AU  - Marković, Bojan
AU  - Ignjatović, Janko
AU  - Vujadinović, Mirjana
AU  - Savić, Vedrana
AU  - Vladimirov, Sote
AU  - Karljiković-Rajić, Katarina
PY  - 2015
UR  - https://farfar.pharmacy.bg.ac.rs/handle/123456789/2323
AB  - Inter-laboratory verification of European pharmacopoeia (EP) monograph on derivative spectrophotometry (DS) method and its application for chitosan hydrochloride was carried out on two generation of instruments (earlier GBC Cintra 20 and current technology TS Evolution 300). Instruments operate with different versions of Savitzky-Golay algorithm and modes of generating digital derivative spectra. For resolution power parameter, defined as the amplitude ratio A/B in DS method EP monograph, comparable results were obtained only with algorithm's parameters smoothing points (SP) 7 and the 2nd degree polynomial and those provided corresponding data with other two modes on TS Evolution 300 Medium digital indirect and Medium digital direct. Using quoted algorithm's parameters, the differences in percentages between the amplitude ratio A/B averages, were within accepted criteria (+/- 13%) for assay of drug product for method transfer. The deviation of 1.76% for the degree of deacetylation assessment of chitosan hydrochloride, determined on two instruments, (amplitude D-1(202); the 2nd degree polynomial and SP 9 in Savitzky-Golay algorithm), was acceptable, since it was within allowed criteria (+/- 2%) for assay deviation of drug substance, for method transfer in pharmaceutical analyses.
PB  - Pergamon-Elsevier Science Ltd, Oxford
T2  - Spectroscopy Letters
T1  - Inter-laboratory verification of European pharmacopoeia monograph on derivative spectrophotometry method and its application for chitosan hydrochloride
VL  - 150
SP  - 792
EP  - 798
DO  - 10.1016/j.saa.2015.06.022
ER  - 

@article{
author = "Marković, Bojan and Ignjatović, Janko and Vujadinović, Mirjana and Savić, Vedrana and Vladimirov, Sote and Karljiković-Rajić, Katarina",
year = "2015",
abstract = "Inter-laboratory verification of European pharmacopoeia (EP) monograph on derivative spectrophotometry (DS) method and its application for chitosan hydrochloride was carried out on two generation of instruments (earlier GBC Cintra 20 and current technology TS Evolution 300). Instruments operate with different versions of Savitzky-Golay algorithm and modes of generating digital derivative spectra. For resolution power parameter, defined as the amplitude ratio A/B in DS method EP monograph, comparable results were obtained only with algorithm's parameters smoothing points (SP) 7 and the 2nd degree polynomial and those provided corresponding data with other two modes on TS Evolution 300 Medium digital indirect and Medium digital direct. Using quoted algorithm's parameters, the differences in percentages between the amplitude ratio A/B averages, were within accepted criteria (+/- 13%) for assay of drug product for method transfer. The deviation of 1.76% for the degree of deacetylation assessment of chitosan hydrochloride, determined on two instruments, (amplitude D-1(202); the 2nd degree polynomial and SP 9 in Savitzky-Golay algorithm), was acceptable, since it was within allowed criteria (+/- 2%) for assay deviation of drug substance, for method transfer in pharmaceutical analyses.",
publisher = "Pergamon-Elsevier Science Ltd, Oxford",
journal = "Spectroscopy Letters",
title = "Inter-laboratory verification of European pharmacopoeia monograph on derivative spectrophotometry method and its application for chitosan hydrochloride",
volume = "150",
pages = "792-798",
doi = "10.1016/j.saa.2015.06.022"
}

Marković, B., Ignjatović, J., Vujadinović, M., Savić, V., Vladimirov, S.,& Karljiković-Rajić, K.. (2015). Inter-laboratory verification of European pharmacopoeia monograph on derivative spectrophotometry method and its application for chitosan hydrochloride. in Spectroscopy Letters
Pergamon-Elsevier Science Ltd, Oxford., 150, 792-798.
https://doi.org/10.1016/j.saa.2015.06.022

Marković B, Ignjatović J, Vujadinović M, Savić V, Vladimirov S, Karljiković-Rajić K. Inter-laboratory verification of European pharmacopoeia monograph on derivative spectrophotometry method and its application for chitosan hydrochloride. in Spectroscopy Letters. 2015;150:792-798.
doi:10.1016/j.saa.2015.06.022 .

Marković, Bojan, Ignjatović, Janko, Vujadinović, Mirjana, Savić, Vedrana, Vladimirov, Sote, Karljiković-Rajić, Katarina, "Inter-laboratory verification of European pharmacopoeia monograph on derivative spectrophotometry method and its application for chitosan hydrochloride" in Spectroscopy Letters, 150 (2015):792-798,
https://doi.org/10.1016/j.saa.2015.06.022 . .

TY  - JOUR
AU  - Odović, Jadranka
AU  - Marković, Bojan
AU  - Vladimirov, Sote
AU  - Karljiković-Rajić, Katarina
PY  - 2015
UR  - https://farfar.pharmacy.bg.ac.rs/handle/123456789/2354
AB  - Twelve angiotensin-converting enzyme (ACE) inhibitors were studied to evaluate correlation between their absorption (ABS) data available in the literature (22-96%) and hydrophobicity parameters (k(m) and P-m/w) obtained in micellar thin-layer chromatography (MTLC) using Brij 35. The theoretical considerations showed that the geometric molecular descriptor-volume value (Vol) should be considered as an independent variable simultaneously with calculated hydrophobicity parameters in multiple linear regression analysis to obtain reliable correlation between ACE inhibitor's absorption and lipophilicity (calculated KOWWINlog P) and that captopril should be excluded from further correlations. The results of MTLC confirmed that between the two hydrophobicity parameters k(m) and P-m/w, for absorption prediction of 11 ACE inhibitors, the micelle-water partition coefficient P-m/w provided higher correlation (R-2 = 0.756), while for the k(m) parameter R-2 = 0.612 was obtained. The micelle-water partition coefficient Pm/w could be considered as analogous to hydrophobicity parameter C-0 from reversed-phase thin-layer chromatography. Dissimilar retention behavior of lisinopril indicated its lowest non-polar interaction with micelle, because of its di-acid form. The proposed model which included ACE inhibitors on the opposite site of lipophilicity-lisinopril and fosinopril (KOWWINlog P = -0.96 and KOWWINlog P = 6.61, respectively), both with similar absorption values (25 and 36%, respectively), could indicate that absorption of investigated compounds occurs via two different mechanisms: active and passive transport.
PB  - Oxford Univ Press Inc, Cary
T2  - Journal of Chromatographic Science
T1  - Evaluation of Angiotensin-Converting Enzyme Inhibitor's Absorption with Retention Data of Micellar Thin-Layer Chromatography and Suitable Molecular Descriptor
VL  - 53
IS  - 10
SP  - 1780
EP  - 1785
DO  - 10.1093/chromsci/bmv091
ER  - 

@article{
author = "Odović, Jadranka and Marković, Bojan and Vladimirov, Sote and Karljiković-Rajić, Katarina",
year = "2015",
abstract = "Twelve angiotensin-converting enzyme (ACE) inhibitors were studied to evaluate correlation between their absorption (ABS) data available in the literature (22-96%) and hydrophobicity parameters (k(m) and P-m/w) obtained in micellar thin-layer chromatography (MTLC) using Brij 35. The theoretical considerations showed that the geometric molecular descriptor-volume value (Vol) should be considered as an independent variable simultaneously with calculated hydrophobicity parameters in multiple linear regression analysis to obtain reliable correlation between ACE inhibitor's absorption and lipophilicity (calculated KOWWINlog P) and that captopril should be excluded from further correlations. The results of MTLC confirmed that between the two hydrophobicity parameters k(m) and P-m/w, for absorption prediction of 11 ACE inhibitors, the micelle-water partition coefficient P-m/w provided higher correlation (R-2 = 0.756), while for the k(m) parameter R-2 = 0.612 was obtained. The micelle-water partition coefficient Pm/w could be considered as analogous to hydrophobicity parameter C-0 from reversed-phase thin-layer chromatography. Dissimilar retention behavior of lisinopril indicated its lowest non-polar interaction with micelle, because of its di-acid form. The proposed model which included ACE inhibitors on the opposite site of lipophilicity-lisinopril and fosinopril (KOWWINlog P = -0.96 and KOWWINlog P = 6.61, respectively), both with similar absorption values (25 and 36%, respectively), could indicate that absorption of investigated compounds occurs via two different mechanisms: active and passive transport.",
publisher = "Oxford Univ Press Inc, Cary",
journal = "Journal of Chromatographic Science",
title = "Evaluation of Angiotensin-Converting Enzyme Inhibitor's Absorption with Retention Data of Micellar Thin-Layer Chromatography and Suitable Molecular Descriptor",
volume = "53",
number = "10",
pages = "1780-1785",
doi = "10.1093/chromsci/bmv091"
}

Odović, J., Marković, B., Vladimirov, S.,& Karljiković-Rajić, K.. (2015). Evaluation of Angiotensin-Converting Enzyme Inhibitor's Absorption with Retention Data of Micellar Thin-Layer Chromatography and Suitable Molecular Descriptor. in Journal of Chromatographic Science
Oxford Univ Press Inc, Cary., 53(10), 1780-1785.
https://doi.org/10.1093/chromsci/bmv091

Odović J, Marković B, Vladimirov S, Karljiković-Rajić K. Evaluation of Angiotensin-Converting Enzyme Inhibitor's Absorption with Retention Data of Micellar Thin-Layer Chromatography and Suitable Molecular Descriptor. in Journal of Chromatographic Science. 2015;53(10):1780-1785.
doi:10.1093/chromsci/bmv091 .

Odović, Jadranka, Marković, Bojan, Vladimirov, Sote, Karljiković-Rajić, Katarina, "Evaluation of Angiotensin-Converting Enzyme Inhibitor's Absorption with Retention Data of Micellar Thin-Layer Chromatography and Suitable Molecular Descriptor" in Journal of Chromatographic Science, 53, no. 10 (2015):1780-1785,
https://doi.org/10.1093/chromsci/bmv091 . .

TY  - JOUR
AU  - Odović, Jadranka
AU  - Marković, Bojan
AU  - Vladimirov, Sote
AU  - Karljiković-Rajić, Katarina
PY  - 2014
UR  - https://farfar.pharmacy.bg.ac.rs/handle/123456789/2160
AB  - Set of nine angiotensin-converting enzyme inhibitors (enalapril, quinapril, fosinopril, lisinopril, cilazapril, ramipril, benazepril, perindopril and moexipril) were studied to evaluate the correlation between their intestinal absorption and salting-out thin-layer chromatography hydrophobicity parameters (R-M(0) or C-0) obtained by ascending technique applying four different salts, (NH4)(2)SO4, NH4NO3, NH4Cl and NaCl as mobile phases. The best correlations between KOWWIN log P and both hydrophobicity parameters, R-M(0) and C-0, (R-2 > 0.850) were observed for NaCl (1.0-3.0 M) while the lowest R-2 was obtained for (NH4)(2)SO4 (0.649 and 0.427, respectively) due to highest salting-out effect of (NH4)(2)SO4. The effect of selected inorganic salts in the salting-out mobile phases, on the solutes solubility and retention was evaluated. The topological polar surface area should be selected as independent variable (only this molecular descriptor showed low correlation with chromatographic hydrophobicity parameters) for multiple linear regression analysis, to obtain reliable correlation between angiotensin-converting enzyme inhibitor's intestinal absorption data and salting-out thin-layer chromatograpic hydrophobicity parameters. These correlations provide R-2 =0.823 for R-M(0) or R-2 =0.799 for C-0 indicating good relationship between predicted and literature available intestinal absorption (ranged from 22% to 70%) of investigated angiotensin-converting enzyme inhibitors. The proposed in vitro model was checked with three in addition experimentally analyzed drugs, zofenopril, trandolapril and captoril. The satisfactory absorption prediction was obtained for zofenopril and trandolapril, while divergence established for captopril resulted from considerably different structure.
PB  - Elsevier Science BV, Amsterdam
T2  - Journal of Chromatography B-Analytical Technologies in the Biomedical and Life Sciences
T1  - In Vitro modeling of angiotensin-converting enzyme inhibitor's absorption with chromatographic retention data and selected molecular descriptors
VL  - 953
SP  - 102
EP  - 107
DO  - 10.1016/j.jchromb.2014.02.004
ER  - 

@article{
author = "Odović, Jadranka and Marković, Bojan and Vladimirov, Sote and Karljiković-Rajić, Katarina",
year = "2014",
abstract = "Set of nine angiotensin-converting enzyme inhibitors (enalapril, quinapril, fosinopril, lisinopril, cilazapril, ramipril, benazepril, perindopril and moexipril) were studied to evaluate the correlation between their intestinal absorption and salting-out thin-layer chromatography hydrophobicity parameters (R-M(0) or C-0) obtained by ascending technique applying four different salts, (NH4)(2)SO4, NH4NO3, NH4Cl and NaCl as mobile phases. The best correlations between KOWWIN log P and both hydrophobicity parameters, R-M(0) and C-0, (R-2 > 0.850) were observed for NaCl (1.0-3.0 M) while the lowest R-2 was obtained for (NH4)(2)SO4 (0.649 and 0.427, respectively) due to highest salting-out effect of (NH4)(2)SO4. The effect of selected inorganic salts in the salting-out mobile phases, on the solutes solubility and retention was evaluated. The topological polar surface area should be selected as independent variable (only this molecular descriptor showed low correlation with chromatographic hydrophobicity parameters) for multiple linear regression analysis, to obtain reliable correlation between angiotensin-converting enzyme inhibitor's intestinal absorption data and salting-out thin-layer chromatograpic hydrophobicity parameters. These correlations provide R-2 =0.823 for R-M(0) or R-2 =0.799 for C-0 indicating good relationship between predicted and literature available intestinal absorption (ranged from 22% to 70%) of investigated angiotensin-converting enzyme inhibitors. The proposed in vitro model was checked with three in addition experimentally analyzed drugs, zofenopril, trandolapril and captoril. The satisfactory absorption prediction was obtained for zofenopril and trandolapril, while divergence established for captopril resulted from considerably different structure.",
publisher = "Elsevier Science BV, Amsterdam",
journal = "Journal of Chromatography B-Analytical Technologies in the Biomedical and Life Sciences",
title = "In Vitro modeling of angiotensin-converting enzyme inhibitor's absorption with chromatographic retention data and selected molecular descriptors",
volume = "953",
pages = "102-107",
doi = "10.1016/j.jchromb.2014.02.004"
}

Odović, J., Marković, B., Vladimirov, S.,& Karljiković-Rajić, K.. (2014). In Vitro modeling of angiotensin-converting enzyme inhibitor's absorption with chromatographic retention data and selected molecular descriptors. in Journal of Chromatography B-Analytical Technologies in the Biomedical and Life Sciences
Elsevier Science BV, Amsterdam., 953, 102-107.
https://doi.org/10.1016/j.jchromb.2014.02.004

Odović J, Marković B, Vladimirov S, Karljiković-Rajić K. In Vitro modeling of angiotensin-converting enzyme inhibitor's absorption with chromatographic retention data and selected molecular descriptors. in Journal of Chromatography B-Analytical Technologies in the Biomedical and Life Sciences. 2014;953:102-107.
doi:10.1016/j.jchromb.2014.02.004 .

Odović, Jadranka, Marković, Bojan, Vladimirov, Sote, Karljiković-Rajić, Katarina, "In Vitro modeling of angiotensin-converting enzyme inhibitor's absorption with chromatographic retention data and selected molecular descriptors" in Journal of Chromatography B-Analytical Technologies in the Biomedical and Life Sciences, 953 (2014):102-107,
https://doi.org/10.1016/j.jchromb.2014.02.004 . .

TY  - CONF
AU  - Odović, Jadranka
AU  - Marković, Bojan
AU  - Vladimirov, Sote
AU  - Karljiković-Rajić, Katarina
PY  - 2013
UR  - https://farfar.pharmacy.bg.ac.rs/handle/123456789/5363
AB  - Lipophilicity is one of the most significant biologically active substances properties that
attract considerable interest in medicinal chemistry, pharmacokinetics and environmental
science. Lipophilicity influences drugs absorption, distribution, binding to plasma proteins
and elimination. Thin-layer chromatography (TLC) is known as well established method for
lipophilicity evaluation. Angiotensin – converting enzyme (ACE) inhibitors represent the
group of drugs widely used in treatment of hypertension. In addition to our previous
chromatographic studies of ACE inhibitors [1] in this work lipophilicity of ten ACE inhibitors
under conditions of micellar thin-layer chromatography has been examined.
The substances investigated were: 1. Lisinopril, 2. Cilazapril, 3. Enalapril, 4. Perindopril, 5.
Ramipril, 6. Moexipril, 7. Benazepril, 8. Quinapril, 9. Zofenopril, 10. Fosinopril. The
experiments were performed on RP-TLC C18 plates, commercially available, (Art. 5559, E.
Merck, Germany). The plates were spotted with 1μL aliquots of freshly prepared ethanolic
solutions (about 2mg/mL) of investigated drugs. The mobile phase was composed of 20%
tetrahydrofuran (THF) and 80% phosphate buffer (pH = 6.8) with addition of
polyoxyethylene (23) lauryl ether, Brij 35, (0.01-0.06 M). After development, by ascending
technique, the detection was performed under UV lump. All investigations were
performed at room temperature (25  2 C).
The increase of micelle concentration in mobile phase led to decrease of retention of all
lipophilic investigated substances. Only lisinopril as very polar compound showed increase
of retention with increase of micelle concentration. The linear dependences between Brij
35 concentrations and RM values were established for all investigated compounds. From
these linear relationships, values of RM
0 (intercept) and m (slope) were obtained and C0
values for each solute were calculated (C0 = -RM
0/m).
The correlations between hydrophobicity parameters RM
0 or C0 and KOWWIN logP were
investigated. The very good correlation with r2 = 0.8606 was established for RM
0 and
KOWWIN logP relationship, while for C0 and KOWWIN logP significantly lower correlation
was obtained r2 = 0.2878 probably due to micelle’s concentration influence on solutes
retention rate.
PB  - Serbian Chemical Society
C3  - ICOSECS 8, 8th International Conference of the Chemical Societies of the South-East European Countries, BOOK OF ABSTRACTS, Belgrade, Serbia, June 27-29
T1  - Micellar thin-layer chromatography in angiotensin-converting enzyme inhibitors lipophilicity evaluation
SP  - 208
EP  - 208
UR  - https://hdl.handle.net/21.15107/rcub_farfar_5363
ER  - 

@conference{
author = "Odović, Jadranka and Marković, Bojan and Vladimirov, Sote and Karljiković-Rajić, Katarina",
year = "2013",
abstract = "Lipophilicity is one of the most significant biologically active substances properties that
attract considerable interest in medicinal chemistry, pharmacokinetics and environmental
science. Lipophilicity influences drugs absorption, distribution, binding to plasma proteins
and elimination. Thin-layer chromatography (TLC) is known as well established method for
lipophilicity evaluation. Angiotensin – converting enzyme (ACE) inhibitors represent the
group of drugs widely used in treatment of hypertension. In addition to our previous
chromatographic studies of ACE inhibitors [1] in this work lipophilicity of ten ACE inhibitors
under conditions of micellar thin-layer chromatography has been examined.
The substances investigated were: 1. Lisinopril, 2. Cilazapril, 3. Enalapril, 4. Perindopril, 5.
Ramipril, 6. Moexipril, 7. Benazepril, 8. Quinapril, 9. Zofenopril, 10. Fosinopril. The
experiments were performed on RP-TLC C18 plates, commercially available, (Art. 5559, E.
Merck, Germany). The plates were spotted with 1μL aliquots of freshly prepared ethanolic
solutions (about 2mg/mL) of investigated drugs. The mobile phase was composed of 20%
tetrahydrofuran (THF) and 80% phosphate buffer (pH = 6.8) with addition of
polyoxyethylene (23) lauryl ether, Brij 35, (0.01-0.06 M). After development, by ascending
technique, the detection was performed under UV lump. All investigations were
performed at room temperature (25  2 C).
The increase of micelle concentration in mobile phase led to decrease of retention of all
lipophilic investigated substances. Only lisinopril as very polar compound showed increase
of retention with increase of micelle concentration. The linear dependences between Brij
35 concentrations and RM values were established for all investigated compounds. From
these linear relationships, values of RM
0 (intercept) and m (slope) were obtained and C0
values for each solute were calculated (C0 = -RM
0/m).
The correlations between hydrophobicity parameters RM
0 or C0 and KOWWIN logP were
investigated. The very good correlation with r2 = 0.8606 was established for RM
0 and
KOWWIN logP relationship, while for C0 and KOWWIN logP significantly lower correlation
was obtained r2 = 0.2878 probably due to micelle’s concentration influence on solutes
retention rate.",
publisher = "Serbian Chemical Society",
journal = "ICOSECS 8, 8th International Conference of the Chemical Societies of the South-East European Countries, BOOK OF ABSTRACTS, Belgrade, Serbia, June 27-29",
title = "Micellar thin-layer chromatography in angiotensin-converting enzyme inhibitors lipophilicity evaluation",
pages = "208-208",
url = "https://hdl.handle.net/21.15107/rcub_farfar_5363"
}

Odović, J., Marković, B., Vladimirov, S.,& Karljiković-Rajić, K.. (2013). Micellar thin-layer chromatography in angiotensin-converting enzyme inhibitors lipophilicity evaluation. in ICOSECS 8, 8th International Conference of the Chemical Societies of the South-East European Countries, BOOK OF ABSTRACTS, Belgrade, Serbia, June 27-29
Serbian Chemical Society., 208-208.
https://hdl.handle.net/21.15107/rcub_farfar_5363

Odović J, Marković B, Vladimirov S, Karljiković-Rajić K. Micellar thin-layer chromatography in angiotensin-converting enzyme inhibitors lipophilicity evaluation. in ICOSECS 8, 8th International Conference of the Chemical Societies of the South-East European Countries, BOOK OF ABSTRACTS, Belgrade, Serbia, June 27-29. 2013;:208-208.
https://hdl.handle.net/21.15107/rcub_farfar_5363 .

Odović, Jadranka, Marković, Bojan, Vladimirov, Sote, Karljiković-Rajić, Katarina, "Micellar thin-layer chromatography in angiotensin-converting enzyme inhibitors lipophilicity evaluation" in ICOSECS 8, 8th International Conference of the Chemical Societies of the South-East European Countries, BOOK OF ABSTRACTS, Belgrade, Serbia, June 27-29 (2013):208-208,
https://hdl.handle.net/21.15107/rcub_farfar_5363 .

TY  - JOUR
AU  - Odović, Jadranka
AU  - Marković, Bojan
AU  - Trbojević-Stanković, Jasna
AU  - Vladimirov, Sote
AU  - Karljiković-Rajić, Katarina
PY  - 2013
UR  - https://farfar.pharmacy.bg.ac.rs/handle/123456789/2066
AB  - The aim of this study was to compare different calculation methods to determine the lipophilicity, expressed as log P value, of seven ACE inhibitors (enalapril, quinapril, fosinopril, lisinopril, cilazapril, ramipril and benazepril) with significantly different structures. Experimentally determined n-octanol/water partition coefficients, log PO/W values, were obtained from relevant literature. The correlations between all collected log P values were studied and the best agreement between calculated log P and experimentally determined log PO/W values was observed for KOWWINlog P or Milog P values (r = 0.999 or r = 0.974, respectively). The correlations between all collected log P values and chromatographically (reversed-phase thin-layer chromatography) obtained hydrophobicity parameters, RM 0 and C0, were established. Good correlations (r > 0.90) were obtained in the majority of relationships. The KOWWINlog P was established as the most suitable hydrophobicity parameter of the investigated group of ACE inhibitors with r = 0.981 for correlation with RM 0 and r = = 0.977 for correlation with C0 parameters (water-methanol mobile phase). Using multiple linear regressions, it was established that application of two selected log P, calculated by different mathematical approaches, led to very good correlation due to the benefits of both calculation methods. The good relationships indicate that the computed log P, with careful selection of method calculation, can be useful in ACE inhibitors lipophilicity evaluation, as a high-throughput screening technique.
AB  - U radu je analizirana lipofilnost sedam ACE inhibitora (enalapril, kvinapril, fosinopril, lizinopril, cilazapril, ramipril i benazepril) različitih hemijskih struktura. Primenom programskih paketa izračunato je deset različitih deskriptora lipofilnosti, log P vrednosti, za ispitivane ACE inhibitore dok su njihovi eksperimentalno određeni n-oktanol/voda koeficijenti raspodele (log PO/W) preuzeti iz stručne literature. Između izračunatih log P vrednosti uočene su značajne razlike zbog razlika u primenjenim metodama izračunavanja. Ispitane su korelacije između svih log P vrednosti. Najbolje slaganje je dobijeno između eksperimentalnih log PO/W i izračunatih KOWWINlog P (r = 0,999) ili Milog P vrednosti (r = 0,974). Analiziran je odnos između svih log P vrednosti i hromatografski određenih parametara hidrofobnosti, RM 0 i C0 (reverzno-fazna hromatografija na tankom sloju). Za najveći broj zavisnosti dobijene su dobre korelacije (r > 0,90). Najbolja korelacija dobijena je između KOWWINlog P i RM 0 (r = 0,981), odnosno C0 (r = 0,977) (voda-metanol mobilna faza). Multiplom linearnom regresionom analizom utvrđeno je da se primenom dve odabrane log P vrednosti, koje su izračunate korišćenjem različitih metoda, dobijaju odlične zavisnosti zahvaljujući prednostima primenjenih metoda. Dobijene dobre zavisnosti ukazuju da matematičke metode izračunavanja, kao tehnike za analizu velikog broja rezultata u kratkom vremenskom periodu (eng. high-throughput screening techniques), mogu biti od velike koristi u proceni lipofilnosti ACE inhibitora.
PB  - Savez hemijskih inženjera, Beograd
T2  - Hemijska industrija
T1  - Evaluation of ACE inhibitors lipophilicity using in silico and chromatographically obtained hydrophobicity parameters
T1  - Procena lipofilnosti ACE inhibitora primenom in silico i hromatografski dobijenih parametara hidrofobnosti
VL  - 67
IS  - 2
SP  - 209
EP  - 216
DO  - 10.2298/HEMIND120522078O
ER  - 

@article{
author = "Odović, Jadranka and Marković, Bojan and Trbojević-Stanković, Jasna and Vladimirov, Sote and Karljiković-Rajić, Katarina",
year = "2013",
abstract = "The aim of this study was to compare different calculation methods to determine the lipophilicity, expressed as log P value, of seven ACE inhibitors (enalapril, quinapril, fosinopril, lisinopril, cilazapril, ramipril and benazepril) with significantly different structures. Experimentally determined n-octanol/water partition coefficients, log PO/W values, were obtained from relevant literature. The correlations between all collected log P values were studied and the best agreement between calculated log P and experimentally determined log PO/W values was observed for KOWWINlog P or Milog P values (r = 0.999 or r = 0.974, respectively). The correlations between all collected log P values and chromatographically (reversed-phase thin-layer chromatography) obtained hydrophobicity parameters, RM 0 and C0, were established. Good correlations (r > 0.90) were obtained in the majority of relationships. The KOWWINlog P was established as the most suitable hydrophobicity parameter of the investigated group of ACE inhibitors with r = 0.981 for correlation with RM 0 and r = = 0.977 for correlation with C0 parameters (water-methanol mobile phase). Using multiple linear regressions, it was established that application of two selected log P, calculated by different mathematical approaches, led to very good correlation due to the benefits of both calculation methods. The good relationships indicate that the computed log P, with careful selection of method calculation, can be useful in ACE inhibitors lipophilicity evaluation, as a high-throughput screening technique., U radu je analizirana lipofilnost sedam ACE inhibitora (enalapril, kvinapril, fosinopril, lizinopril, cilazapril, ramipril i benazepril) različitih hemijskih struktura. Primenom programskih paketa izračunato je deset različitih deskriptora lipofilnosti, log P vrednosti, za ispitivane ACE inhibitore dok su njihovi eksperimentalno određeni n-oktanol/voda koeficijenti raspodele (log PO/W) preuzeti iz stručne literature. Između izračunatih log P vrednosti uočene su značajne razlike zbog razlika u primenjenim metodama izračunavanja. Ispitane su korelacije između svih log P vrednosti. Najbolje slaganje je dobijeno između eksperimentalnih log PO/W i izračunatih KOWWINlog P (r = 0,999) ili Milog P vrednosti (r = 0,974). Analiziran je odnos između svih log P vrednosti i hromatografski određenih parametara hidrofobnosti, RM 0 i C0 (reverzno-fazna hromatografija na tankom sloju). Za najveći broj zavisnosti dobijene su dobre korelacije (r > 0,90). Najbolja korelacija dobijena je između KOWWINlog P i RM 0 (r = 0,981), odnosno C0 (r = 0,977) (voda-metanol mobilna faza). Multiplom linearnom regresionom analizom utvrđeno je da se primenom dve odabrane log P vrednosti, koje su izračunate korišćenjem različitih metoda, dobijaju odlične zavisnosti zahvaljujući prednostima primenjenih metoda. Dobijene dobre zavisnosti ukazuju da matematičke metode izračunavanja, kao tehnike za analizu velikog broja rezultata u kratkom vremenskom periodu (eng. high-throughput screening techniques), mogu biti od velike koristi u proceni lipofilnosti ACE inhibitora.",
publisher = "Savez hemijskih inženjera, Beograd",
journal = "Hemijska industrija",
title = "Evaluation of ACE inhibitors lipophilicity using in silico and chromatographically obtained hydrophobicity parameters, Procena lipofilnosti ACE inhibitora primenom in silico i hromatografski dobijenih parametara hidrofobnosti",
volume = "67",
number = "2",
pages = "209-216",
doi = "10.2298/HEMIND120522078O"
}

Odović, J., Marković, B., Trbojević-Stanković, J., Vladimirov, S.,& Karljiković-Rajić, K.. (2013). Evaluation of ACE inhibitors lipophilicity using in silico and chromatographically obtained hydrophobicity parameters. in Hemijska industrija
Savez hemijskih inženjera, Beograd., 67(2), 209-216.
https://doi.org/10.2298/HEMIND120522078O

Odović J, Marković B, Trbojević-Stanković J, Vladimirov S, Karljiković-Rajić K. Evaluation of ACE inhibitors lipophilicity using in silico and chromatographically obtained hydrophobicity parameters. in Hemijska industrija. 2013;67(2):209-216.
doi:10.2298/HEMIND120522078O .

Odović, Jadranka, Marković, Bojan, Trbojević-Stanković, Jasna, Vladimirov, Sote, Karljiković-Rajić, Katarina, "Evaluation of ACE inhibitors lipophilicity using in silico and chromatographically obtained hydrophobicity parameters" in Hemijska industrija, 67, no. 2 (2013):209-216,
https://doi.org/10.2298/HEMIND120522078O . .

TY  - JOUR
AU  - Marković, Bojan
AU  - Vladimirov, Sote
AU  - Čudina, Olivera
AU  - Odović, Jadranka
AU  - Karljiković-Rajić, Katarina
PY  - 2012
UR  - https://farfar.pharmacy.bg.ac.rs/handle/123456789/1722
AB  - The permeation properties of twenty newly synthesized alpha-alkoxyalkanoyl and alpha-aryloxyalkanoyl C-21 esters of standard corticosteroids: Fluocinolone acetonide, dexamethasone, triamcinolone acetonide and hydrocortisone were established using a PAMPA assay (70% silicone oil and 30% isopropyl myristate). The data were compared with parent corticosteroids with addition of mometasone furoate and hydrocortisone acetate. All newly synthesized corticosteroid C-21 esters have effective permeability coefficients higher then -6, mostly followed with high values of retention factors and low permeation. The examined compounds were grouped through relationship between obtained retention factors and permeation parameters (groups I-III). The classification confirmed group I (membrane retentions as well as permeation lower then 30%) for all corticosteroid standards except mometasone furoate, a potent topical corticosteroid which, with high membrane retention (81%) and low permeation (7.7%) fits into group III. The largest number of new synthesized corticosteroids C-21 esters, among them all fluocinolone acetonide C-21 esters, have high membrane retentions (32.4%-86.5%) and low permeations (1.3%-27.1%), fitting in group III. The classification was related to previously obtained anti-inflammatory activity data for the fluocinolone acetonide C-21 esters series. According to the PAMPA results the new synthesized esters could be considered as potential new prodrugs with useful benefit/risk ratio.
PB  - MDPI, Basel
T2  - Molecules
T1  - A PAMPA Assay as Fast Predictive Model of Passive Human Skin Permeability of New Synthesized Corticosteroid C-21 Esters
VL  - 17
IS  - 1
SP  - 480
EP  - 491
DO  - 10.3390/molecules17010480
ER  - 

@article{
author = "Marković, Bojan and Vladimirov, Sote and Čudina, Olivera and Odović, Jadranka and Karljiković-Rajić, Katarina",
year = "2012",
abstract = "The permeation properties of twenty newly synthesized alpha-alkoxyalkanoyl and alpha-aryloxyalkanoyl C-21 esters of standard corticosteroids: Fluocinolone acetonide, dexamethasone, triamcinolone acetonide and hydrocortisone were established using a PAMPA assay (70% silicone oil and 30% isopropyl myristate). The data were compared with parent corticosteroids with addition of mometasone furoate and hydrocortisone acetate. All newly synthesized corticosteroid C-21 esters have effective permeability coefficients higher then -6, mostly followed with high values of retention factors and low permeation. The examined compounds were grouped through relationship between obtained retention factors and permeation parameters (groups I-III). The classification confirmed group I (membrane retentions as well as permeation lower then 30%) for all corticosteroid standards except mometasone furoate, a potent topical corticosteroid which, with high membrane retention (81%) and low permeation (7.7%) fits into group III. The largest number of new synthesized corticosteroids C-21 esters, among them all fluocinolone acetonide C-21 esters, have high membrane retentions (32.4%-86.5%) and low permeations (1.3%-27.1%), fitting in group III. The classification was related to previously obtained anti-inflammatory activity data for the fluocinolone acetonide C-21 esters series. According to the PAMPA results the new synthesized esters could be considered as potential new prodrugs with useful benefit/risk ratio.",
publisher = "MDPI, Basel",
journal = "Molecules",
title = "A PAMPA Assay as Fast Predictive Model of Passive Human Skin Permeability of New Synthesized Corticosteroid C-21 Esters",
volume = "17",
number = "1",
pages = "480-491",
doi = "10.3390/molecules17010480"
}

Marković, B., Vladimirov, S., Čudina, O., Odović, J.,& Karljiković-Rajić, K.. (2012). A PAMPA Assay as Fast Predictive Model of Passive Human Skin Permeability of New Synthesized Corticosteroid C-21 Esters. in Molecules
MDPI, Basel., 17(1), 480-491.
https://doi.org/10.3390/molecules17010480

Marković B, Vladimirov S, Čudina O, Odović J, Karljiković-Rajić K. A PAMPA Assay as Fast Predictive Model of Passive Human Skin Permeability of New Synthesized Corticosteroid C-21 Esters. in Molecules. 2012;17(1):480-491.
doi:10.3390/molecules17010480 .

Marković, Bojan, Vladimirov, Sote, Čudina, Olivera, Odović, Jadranka, Karljiković-Rajić, Katarina, "A PAMPA Assay as Fast Predictive Model of Passive Human Skin Permeability of New Synthesized Corticosteroid C-21 Esters" in Molecules, 17, no. 1 (2012):480-491,
https://doi.org/10.3390/molecules17010480 . .

TY  - JOUR
AU  - Čudina, Olivera
AU  - Marković, Bojan
AU  - Karljiković-Rajić, Katarina
AU  - Vladimirov, Sote
PY  - 2012
UR  - https://farfar.pharmacy.bg.ac.rs/handle/123456789/1750
AB  - Biopartitioning micellar chromatography (BMC), which is useful to mimic the drug partitioning process in biological systems, was used as a method for determination of partition coefficients micelle/water (P-m/w) of a set of structurally diverse drugs. BMC is a chromatographic system consisting of polyoxyethylene (23) lauryl ether (Brij 35) micellar mobile phase prepared in physiological conditions and C-18 reversed stationary phase. The retention factors were determined for all selected and studied compounds and a correlation between P-m/w and oral drug absorption values were obtained. In order to study the similarity between the BMC system and other natural systems of biomembranes, the retention data on BMC were compared with permeability data obtained in Parallel artificial membrane permeation assays (PAMPA lipid model). Molecular descriptors that are believed to influence trans-cellular transport and oral drug absorption have been calculated in order to obtain a predictive and reliable model for drug permeability. Results presented in this paper indicate that a proposed descriptor for hydrophobicity P-m/w, provided, from a statistical point of view, is a better model than other hydrophobicity descriptors.
PB  - Taylor & Francis Inc, Philadelphia
T2  - Analytical Letters
T1  - Biopartitioning Micellar Chromatography-Partition Coefficient Micelle/Water as a Potential Descriptor for Hydrophobicity in Prediction of Oral Drug Absorption
VL  - 45
IS  - 7
SP  - 677
EP  - 688
DO  - 10.1080/00032719.2011.653904
ER  - 

@article{
author = "Čudina, Olivera and Marković, Bojan and Karljiković-Rajić, Katarina and Vladimirov, Sote",
year = "2012",
abstract = "Biopartitioning micellar chromatography (BMC), which is useful to mimic the drug partitioning process in biological systems, was used as a method for determination of partition coefficients micelle/water (P-m/w) of a set of structurally diverse drugs. BMC is a chromatographic system consisting of polyoxyethylene (23) lauryl ether (Brij 35) micellar mobile phase prepared in physiological conditions and C-18 reversed stationary phase. The retention factors were determined for all selected and studied compounds and a correlation between P-m/w and oral drug absorption values were obtained. In order to study the similarity between the BMC system and other natural systems of biomembranes, the retention data on BMC were compared with permeability data obtained in Parallel artificial membrane permeation assays (PAMPA lipid model). Molecular descriptors that are believed to influence trans-cellular transport and oral drug absorption have been calculated in order to obtain a predictive and reliable model for drug permeability. Results presented in this paper indicate that a proposed descriptor for hydrophobicity P-m/w, provided, from a statistical point of view, is a better model than other hydrophobicity descriptors.",
publisher = "Taylor & Francis Inc, Philadelphia",
journal = "Analytical Letters",
title = "Biopartitioning Micellar Chromatography-Partition Coefficient Micelle/Water as a Potential Descriptor for Hydrophobicity in Prediction of Oral Drug Absorption",
volume = "45",
number = "7",
pages = "677-688",
doi = "10.1080/00032719.2011.653904"
}

Čudina, O., Marković, B., Karljiković-Rajić, K.,& Vladimirov, S.. (2012). Biopartitioning Micellar Chromatography-Partition Coefficient Micelle/Water as a Potential Descriptor for Hydrophobicity in Prediction of Oral Drug Absorption. in Analytical Letters
Taylor & Francis Inc, Philadelphia., 45(7), 677-688.
https://doi.org/10.1080/00032719.2011.653904

Čudina O, Marković B, Karljiković-Rajić K, Vladimirov S. Biopartitioning Micellar Chromatography-Partition Coefficient Micelle/Water as a Potential Descriptor for Hydrophobicity in Prediction of Oral Drug Absorption. in Analytical Letters. 2012;45(7):677-688.
doi:10.1080/00032719.2011.653904 .

Čudina, Olivera, Marković, Bojan, Karljiković-Rajić, Katarina, Vladimirov, Sote, "Biopartitioning Micellar Chromatography-Partition Coefficient Micelle/Water as a Potential Descriptor for Hydrophobicity in Prediction of Oral Drug Absorption" in Analytical Letters, 45, no. 7 (2012):677-688,
https://doi.org/10.1080/00032719.2011.653904 . .

TY  - JOUR
AU  - Odović, Jadranka
AU  - Marković, Bojan
AU  - Injac, Rade
AU  - Vladimirov, Sote
AU  - Karljiković-Rajić, Katarina
PY  - 2012
UR  - https://farfar.pharmacy.bg.ac.rs/handle/123456789/1651
AB  - In this research seven ACE inhibitors (enalapril, quinapril, fosinopril, lisinopril, cilazapril, ramipril, benazepril) were studied to evaluate the correlation between their absorption and ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS) and reversed-phase thin-layer chromatography (RP-TLC) hydrophobicity data (phi(0) or C-0 parameters, respectively). Their absorption values were in the range of 25-60%, while calculated KOWWIN logP values were from -0.94 to 6.61. Additionally. perindopril (absorption 70%, KOWWIN logP 2.59) and moexipril (absorption 22%, KOWWIN logP 3.36) were introduced for the theoretical considerations due to their high/low absorption values which were on the opposite sites in comparison with the majority of ACE inhibitors (25-60%). In the theoretical considerations it was shown that the solubility data (logS) must be considered, as independent variable, simultaneously with KOWWIN logP to obtain reliable correlation (r(2) = 0.7208) between absorption and ACE inhibitors lipophilicity. As the main topic of this study, the relationships between literature available and absorption data predicted by multiple linear regression (MLR) using logS values besides chromatographically obtained hydrophobicity parameters C-0 (r(2) = 0.6424) or phi(0) (r(2) = 0.6762) were studied proving that these parameters could be used in ACE inhibitors absorption evaluation. The UHPLC-MS method provides the direct application of experimentally obtained phi(0) values that is the advantage of this method. For better MLR correlation of ACE inhibitors absorption with C-0 parameters (RP-TLC) and logS, mathematical conversion of C-0 parameters to logC(0) values was necessary based on requisite for probability value of regression analysis (P  lt  0.05). The accordance and differences between hydrophobicity parameters obtained by UHPLC-MS and RP-TLC were defined.
PB  - Elsevier Science BV, Amsterdam
T2  - Journal of Chromatography A
T1  - Correlation between ultra-high performance liquid chromatography-tandem mass spectrometry and reversed-phase thin-layer chromatography hydrophobicity data for evaluation of angiotensin-converting enzyme inhibitors absorption
VL  - 1258
SP  - 94
EP  - 100
DO  - 10.1016/j.chroma.2012.08.038
ER  - 

@article{
author = "Odović, Jadranka and Marković, Bojan and Injac, Rade and Vladimirov, Sote and Karljiković-Rajić, Katarina",
year = "2012",
abstract = "In this research seven ACE inhibitors (enalapril, quinapril, fosinopril, lisinopril, cilazapril, ramipril, benazepril) were studied to evaluate the correlation between their absorption and ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS) and reversed-phase thin-layer chromatography (RP-TLC) hydrophobicity data (phi(0) or C-0 parameters, respectively). Their absorption values were in the range of 25-60%, while calculated KOWWIN logP values were from -0.94 to 6.61. Additionally. perindopril (absorption 70%, KOWWIN logP 2.59) and moexipril (absorption 22%, KOWWIN logP 3.36) were introduced for the theoretical considerations due to their high/low absorption values which were on the opposite sites in comparison with the majority of ACE inhibitors (25-60%). In the theoretical considerations it was shown that the solubility data (logS) must be considered, as independent variable, simultaneously with KOWWIN logP to obtain reliable correlation (r(2) = 0.7208) between absorption and ACE inhibitors lipophilicity. As the main topic of this study, the relationships between literature available and absorption data predicted by multiple linear regression (MLR) using logS values besides chromatographically obtained hydrophobicity parameters C-0 (r(2) = 0.6424) or phi(0) (r(2) = 0.6762) were studied proving that these parameters could be used in ACE inhibitors absorption evaluation. The UHPLC-MS method provides the direct application of experimentally obtained phi(0) values that is the advantage of this method. For better MLR correlation of ACE inhibitors absorption with C-0 parameters (RP-TLC) and logS, mathematical conversion of C-0 parameters to logC(0) values was necessary based on requisite for probability value of regression analysis (P  lt  0.05). The accordance and differences between hydrophobicity parameters obtained by UHPLC-MS and RP-TLC were defined.",
publisher = "Elsevier Science BV, Amsterdam",
journal = "Journal of Chromatography A",
title = "Correlation between ultra-high performance liquid chromatography-tandem mass spectrometry and reversed-phase thin-layer chromatography hydrophobicity data for evaluation of angiotensin-converting enzyme inhibitors absorption",
volume = "1258",
pages = "94-100",
doi = "10.1016/j.chroma.2012.08.038"
}

Odović, J., Marković, B., Injac, R., Vladimirov, S.,& Karljiković-Rajić, K.. (2012). Correlation between ultra-high performance liquid chromatography-tandem mass spectrometry and reversed-phase thin-layer chromatography hydrophobicity data for evaluation of angiotensin-converting enzyme inhibitors absorption. in Journal of Chromatography A
Elsevier Science BV, Amsterdam., 1258, 94-100.
https://doi.org/10.1016/j.chroma.2012.08.038

Odović J, Marković B, Injac R, Vladimirov S, Karljiković-Rajić K. Correlation between ultra-high performance liquid chromatography-tandem mass spectrometry and reversed-phase thin-layer chromatography hydrophobicity data for evaluation of angiotensin-converting enzyme inhibitors absorption. in Journal of Chromatography A. 2012;1258:94-100.
doi:10.1016/j.chroma.2012.08.038 .

Odović, Jadranka, Marković, Bojan, Injac, Rade, Vladimirov, Sote, Karljiković-Rajić, Katarina, "Correlation between ultra-high performance liquid chromatography-tandem mass spectrometry and reversed-phase thin-layer chromatography hydrophobicity data for evaluation of angiotensin-converting enzyme inhibitors absorption" in Journal of Chromatography A, 1258 (2012):94-100,
https://doi.org/10.1016/j.chroma.2012.08.038 . .

TY  - JOUR
AU  - Odović, Jadranka
AU  - Karljiković-Rajić, Katarina
AU  - Trbojević-Stanković, Jasna
AU  - Stojimirović, Biljana
AU  - Vladimirov, Sote
PY  - 2012
UR  - https://farfar.pharmacy.bg.ac.rs/handle/123456789/1642
AB  - In this assay, the evaluation of lipophilicity of four ACE-inhibitors and hydrochlorothiazide (HCTZ) with RP-TLC on cellulose layers was described using three binary solvent systems. The selected ACE inhibitors had sufficiently different structures which can indicate the method suitability for their lipophilicity evaluation as the model substances in comparison with HCTZ. In addition, the linear relationship between the R-M-values and composition of mobile phases was established in the current study. From the regression data of the plots, the hydrophobicity parameters, R-M(0) and m, were determined and C-0 parameter was calculated. The correlations between the experimentally obtained hydrophobicity parameters and calculated log p values were studied. Furthermore, the obtained results were compared with those previously obtained on RP-18 modified silica gel. Very good correlation (r = 0.91; water-ethanol solvent system) between the chromatographically obtained hydrophobicity parameters and calculated log p values confirmed the selection of ACE inhibitors since lisinopril and quinapril were on the opposite sites of linear relationship. The results indicate that cellulose as an easily available sorbent can be successfully used for the lipophilicity investigation of examined substances with RP-TLC.
PB  - Shaheed Beheshti Univ, Sch Pharmacy, Tehran
T2  - Iranian Journal of Pharmaceutical Research
T1  - The Lipophilicity Examination of Some ACE inhibitors and Hydrochlorothiazide on Cellulose in RP Thin-Layer Chromatography
VL  - 11
IS  - 3
SP  - 763
EP  - 770
UR  - https://hdl.handle.net/21.15107/rcub_farfar_1642
ER  - 

@article{
author = "Odović, Jadranka and Karljiković-Rajić, Katarina and Trbojević-Stanković, Jasna and Stojimirović, Biljana and Vladimirov, Sote",
year = "2012",
abstract = "In this assay, the evaluation of lipophilicity of four ACE-inhibitors and hydrochlorothiazide (HCTZ) with RP-TLC on cellulose layers was described using three binary solvent systems. The selected ACE inhibitors had sufficiently different structures which can indicate the method suitability for their lipophilicity evaluation as the model substances in comparison with HCTZ. In addition, the linear relationship between the R-M-values and composition of mobile phases was established in the current study. From the regression data of the plots, the hydrophobicity parameters, R-M(0) and m, were determined and C-0 parameter was calculated. The correlations between the experimentally obtained hydrophobicity parameters and calculated log p values were studied. Furthermore, the obtained results were compared with those previously obtained on RP-18 modified silica gel. Very good correlation (r = 0.91; water-ethanol solvent system) between the chromatographically obtained hydrophobicity parameters and calculated log p values confirmed the selection of ACE inhibitors since lisinopril and quinapril were on the opposite sites of linear relationship. The results indicate that cellulose as an easily available sorbent can be successfully used for the lipophilicity investigation of examined substances with RP-TLC.",
publisher = "Shaheed Beheshti Univ, Sch Pharmacy, Tehran",
journal = "Iranian Journal of Pharmaceutical Research",
title = "The Lipophilicity Examination of Some ACE inhibitors and Hydrochlorothiazide on Cellulose in RP Thin-Layer Chromatography",
volume = "11",
number = "3",
pages = "763-770",
url = "https://hdl.handle.net/21.15107/rcub_farfar_1642"
}

Odović, J., Karljiković-Rajić, K., Trbojević-Stanković, J., Stojimirović, B.,& Vladimirov, S.. (2012). The Lipophilicity Examination of Some ACE inhibitors and Hydrochlorothiazide on Cellulose in RP Thin-Layer Chromatography. in Iranian Journal of Pharmaceutical Research
Shaheed Beheshti Univ, Sch Pharmacy, Tehran., 11(3), 763-770.
https://hdl.handle.net/21.15107/rcub_farfar_1642

Odović J, Karljiković-Rajić K, Trbojević-Stanković J, Stojimirović B, Vladimirov S. The Lipophilicity Examination of Some ACE inhibitors and Hydrochlorothiazide on Cellulose in RP Thin-Layer Chromatography. in Iranian Journal of Pharmaceutical Research. 2012;11(3):763-770.
https://hdl.handle.net/21.15107/rcub_farfar_1642 .

Odović, Jadranka, Karljiković-Rajić, Katarina, Trbojević-Stanković, Jasna, Stojimirović, Biljana, Vladimirov, Sote, "The Lipophilicity Examination of Some ACE inhibitors and Hydrochlorothiazide on Cellulose in RP Thin-Layer Chromatography" in Iranian Journal of Pharmaceutical Research, 11, no. 3 (2012):763-770,
https://hdl.handle.net/21.15107/rcub_farfar_1642 .

TY  - JOUR
AU  - Marković, Bojan
AU  - Dobričić, Vladimir
AU  - Vladimirov, Sote
AU  - Čudina, Olivera
AU  - Savić, Vladimir
AU  - Karljiković-Rajić, Katarina
PY  - 2011
UR  - https://farfar.pharmacy.bg.ac.rs/handle/123456789/1524
AB  - In this study the solvolysis of newly synthesized fluocinolone acetonide C-21 esters was analysed in comparison with fluocinonide during a 24-hour period of time. The solvolysis was performed in an ethanol-water (90:10 v/v) mixture using the excess of NaHCO(3). The solvolytic mixtures of each investigated ester have been assayed by a RP-HPLC method using isocratic elution with methanol-water (75:25 v/v); flow rate 1 mL/min; detection at 238 nm; temperature 25 degrees C. Solvolytic rate constants were calculated from the obtained data. Geometry optimizations and charges calculations were carried out by Gaussian W03 software. A good correlation (R = 0.9924) was obtained between solvolytic rate constants and the polarity of the C-O2 bond of those esters. The established relation between solvolytic rate constant (K) and lipophilicity (cLogP) with experimental anti-inflammatory activity could be indicative for topical corticosteroid prodrug activation.
PB  - MDPI, Basel
T2  - Molecules
T1  - Investigation of Solvolysis Kinetics of New Synthesized Fluocinolone Acetonide C-21 Esters-An In Vitro Model for Prodrug Activation
VL  - 16
IS  - 3
SP  - 2658
EP  - 2671
DO  - 10.3390/molecules16032658
ER  - 

@article{
author = "Marković, Bojan and Dobričić, Vladimir and Vladimirov, Sote and Čudina, Olivera and Savić, Vladimir and Karljiković-Rajić, Katarina",
year = "2011",
abstract = "In this study the solvolysis of newly synthesized fluocinolone acetonide C-21 esters was analysed in comparison with fluocinonide during a 24-hour period of time. The solvolysis was performed in an ethanol-water (90:10 v/v) mixture using the excess of NaHCO(3). The solvolytic mixtures of each investigated ester have been assayed by a RP-HPLC method using isocratic elution with methanol-water (75:25 v/v); flow rate 1 mL/min; detection at 238 nm; temperature 25 degrees C. Solvolytic rate constants were calculated from the obtained data. Geometry optimizations and charges calculations were carried out by Gaussian W03 software. A good correlation (R = 0.9924) was obtained between solvolytic rate constants and the polarity of the C-O2 bond of those esters. The established relation between solvolytic rate constant (K) and lipophilicity (cLogP) with experimental anti-inflammatory activity could be indicative for topical corticosteroid prodrug activation.",
publisher = "MDPI, Basel",
journal = "Molecules",
title = "Investigation of Solvolysis Kinetics of New Synthesized Fluocinolone Acetonide C-21 Esters-An In Vitro Model for Prodrug Activation",
volume = "16",
number = "3",
pages = "2658-2671",
doi = "10.3390/molecules16032658"
}

Marković, B., Dobričić, V., Vladimirov, S., Čudina, O., Savić, V.,& Karljiković-Rajić, K.. (2011). Investigation of Solvolysis Kinetics of New Synthesized Fluocinolone Acetonide C-21 Esters-An In Vitro Model for Prodrug Activation. in Molecules
MDPI, Basel., 16(3), 2658-2671.
https://doi.org/10.3390/molecules16032658

Marković B, Dobričić V, Vladimirov S, Čudina O, Savić V, Karljiković-Rajić K. Investigation of Solvolysis Kinetics of New Synthesized Fluocinolone Acetonide C-21 Esters-An In Vitro Model for Prodrug Activation. in Molecules. 2011;16(3):2658-2671.
doi:10.3390/molecules16032658 .

Marković, Bojan, Dobričić, Vladimir, Vladimirov, Sote, Čudina, Olivera, Savić, Vladimir, Karljiković-Rajić, Katarina, "Investigation of Solvolysis Kinetics of New Synthesized Fluocinolone Acetonide C-21 Esters-An In Vitro Model for Prodrug Activation" in Molecules, 16, no. 3 (2011):2658-2671,
https://doi.org/10.3390/molecules16032658 . .

TY  - JOUR
AU  - Marković, Bojan
AU  - Vladimirov, Sote
AU  - Čudina, Olivera
AU  - Savić, Vladimir
AU  - Karljiković-Rajić, Katarina
PY  - 2011
UR  - https://farfar.pharmacy.bg.ac.rs/handle/123456789/1501
AB  - In this study the solvolysis of novel fluocinolone acetonide 21-(2'-phenoxypropionate) in comparison with fluocinonide was analyzed in order to evaluate this process as an in vitro model for prodrug activation. The solvolysis was performed in ethanol: water (90: 10 v/v) mixture using the excess of NaHCO3. The solvolytic mixtures of those esters with different lipophilicity were assayed by proposed RP-HPLC method using isocratic elution with methanol: water (75: 25 v/v); flow rate 1 mL min(-1), and detection at 238 nm. Solvolytic rate constants (at 25 degrees C) for novel prodrug fluocinolone acetonide 21-(2'-phenoxypropionate) (0.0434 h(-1)) and fluocinonide (0.0593 h(-1)) have been compared. This in vitro model of solvolysis and corresponding rate constants are in good correlation with our preliminary data of anti-inflammatory potencies of those prodrugs. Limits of detection, important for the initial stage of solvolysis, were experimentally determined with values of 4.10 mu M and 0.24 mu M for fluocinolone acetonide 21-(2'-phenoxypropionate) and fluocinonide, respectively.
PB  - Taylor & Francis Inc, Philadelphia
T2  - Journal of Liquid Chromatography & Related Technologies
T1  - HPLC evaluation of solvolysis of a novel ester fluocinolone acetonide 21-(2'-phenoxypropionate) in comparison with fluocinonide
VL  - 34
IS  - 19
SP  - 2271
EP  - 2285
DO  - 10.1080/10826076.2011.587223
ER  - 

@article{
author = "Marković, Bojan and Vladimirov, Sote and Čudina, Olivera and Savić, Vladimir and Karljiković-Rajić, Katarina",
year = "2011",
abstract = "In this study the solvolysis of novel fluocinolone acetonide 21-(2'-phenoxypropionate) in comparison with fluocinonide was analyzed in order to evaluate this process as an in vitro model for prodrug activation. The solvolysis was performed in ethanol: water (90: 10 v/v) mixture using the excess of NaHCO3. The solvolytic mixtures of those esters with different lipophilicity were assayed by proposed RP-HPLC method using isocratic elution with methanol: water (75: 25 v/v); flow rate 1 mL min(-1), and detection at 238 nm. Solvolytic rate constants (at 25 degrees C) for novel prodrug fluocinolone acetonide 21-(2'-phenoxypropionate) (0.0434 h(-1)) and fluocinonide (0.0593 h(-1)) have been compared. This in vitro model of solvolysis and corresponding rate constants are in good correlation with our preliminary data of anti-inflammatory potencies of those prodrugs. Limits of detection, important for the initial stage of solvolysis, were experimentally determined with values of 4.10 mu M and 0.24 mu M for fluocinolone acetonide 21-(2'-phenoxypropionate) and fluocinonide, respectively.",
publisher = "Taylor & Francis Inc, Philadelphia",
journal = "Journal of Liquid Chromatography & Related Technologies",
title = "HPLC evaluation of solvolysis of a novel ester fluocinolone acetonide 21-(2'-phenoxypropionate) in comparison with fluocinonide",
volume = "34",
number = "19",
pages = "2271-2285",
doi = "10.1080/10826076.2011.587223"
}

Marković, B., Vladimirov, S., Čudina, O., Savić, V.,& Karljiković-Rajić, K.. (2011). HPLC evaluation of solvolysis of a novel ester fluocinolone acetonide 21-(2'-phenoxypropionate) in comparison with fluocinonide. in Journal of Liquid Chromatography & Related Technologies
Taylor & Francis Inc, Philadelphia., 34(19), 2271-2285.
https://doi.org/10.1080/10826076.2011.587223

Marković B, Vladimirov S, Čudina O, Savić V, Karljiković-Rajić K. HPLC evaluation of solvolysis of a novel ester fluocinolone acetonide 21-(2'-phenoxypropionate) in comparison with fluocinonide. in Journal of Liquid Chromatography & Related Technologies. 2011;34(19):2271-2285.
doi:10.1080/10826076.2011.587223 .

Marković, Bojan, Vladimirov, Sote, Čudina, Olivera, Savić, Vladimir, Karljiković-Rajić, Katarina, "HPLC evaluation of solvolysis of a novel ester fluocinolone acetonide 21-(2'-phenoxypropionate) in comparison with fluocinonide" in Journal of Liquid Chromatography & Related Technologies, 34, no. 19 (2011):2271-2285,
https://doi.org/10.1080/10826076.2011.587223 . .

TY  - JOUR
AU  - Marković, Bojan
AU  - Vladimirov, Sote
AU  - Čudina, Olivera
AU  - Savić, Vladimir
AU  - Karljiković-Rajić, Katarina
PY  - 2010
UR  - https://farfar.pharmacy.bg.ac.rs/handle/123456789/1388
AB  - A novel topical corticosteroid FA-21-PhP, 2-phenoxypropionate ester of fluocinolone acetonide, has been synthesized in order to investigate the possibility of decreasing systemic side effects. In this study model system for in vitro solvolytic reaction of FA-21-PhP has been analyzed in ethanol/water (90:10, v/v) with excess of sodium hydrogen carbonate. The selected conditions have been used as in vitro model for activation of corticosteroid C-21 ester prodrug. The second-order derivative spectrophotometric method (DS) using zero-crossing technique was developed for monitoring ternary mixture of solvolysis. Fluocinolone acetonide (FA) as a solvolyte was determined in the mixture in the concentration range 0.062-0.312 mM using amplitude (2)D(274.9G). Experimentally determined LOD value was 0.0295 mM. The accuracy of proposed DS method was confirmed with HPLC referent method. Peak area of parent ester FA-21-PhP was used for solvolysis monitoring to ensure the initial stage of changes. Linear relationship in HPLC assay for parent ester was obtained in the concentration range 0.054-0.54 mM, with experimentally determined LOD value of 0.0041 mM. Investigated solvolytic reaction in the presence of excess of NaHCO(3) proceeded via a pseudo-first-order kinetic with significant correlation coefficients 0.9891 and 0.9997 for DS and HPLC, respectively. The values of solvolysis rate constant calculated according to DS and HPLC methods are in good accordance 0.038 and 0.043 h(-1), respectively.
PB  - Pergamon-Elsevier Science Ltd, Oxford
T2  - Spectroscopy Letters
T1  - An application of second-order UV-derivative spectrophotometry for study of solvolysis of a novel fluocinolone acetonide ester
VL  - 75
IS  - 2
SP  - 930
EP  - 935
DO  - 10.1016/j.saa.2009.12.043
ER  - 

@article{
author = "Marković, Bojan and Vladimirov, Sote and Čudina, Olivera and Savić, Vladimir and Karljiković-Rajić, Katarina",
year = "2010",
abstract = "A novel topical corticosteroid FA-21-PhP, 2-phenoxypropionate ester of fluocinolone acetonide, has been synthesized in order to investigate the possibility of decreasing systemic side effects. In this study model system for in vitro solvolytic reaction of FA-21-PhP has been analyzed in ethanol/water (90:10, v/v) with excess of sodium hydrogen carbonate. The selected conditions have been used as in vitro model for activation of corticosteroid C-21 ester prodrug. The second-order derivative spectrophotometric method (DS) using zero-crossing technique was developed for monitoring ternary mixture of solvolysis. Fluocinolone acetonide (FA) as a solvolyte was determined in the mixture in the concentration range 0.062-0.312 mM using amplitude (2)D(274.9G). Experimentally determined LOD value was 0.0295 mM. The accuracy of proposed DS method was confirmed with HPLC referent method. Peak area of parent ester FA-21-PhP was used for solvolysis monitoring to ensure the initial stage of changes. Linear relationship in HPLC assay for parent ester was obtained in the concentration range 0.054-0.54 mM, with experimentally determined LOD value of 0.0041 mM. Investigated solvolytic reaction in the presence of excess of NaHCO(3) proceeded via a pseudo-first-order kinetic with significant correlation coefficients 0.9891 and 0.9997 for DS and HPLC, respectively. The values of solvolysis rate constant calculated according to DS and HPLC methods are in good accordance 0.038 and 0.043 h(-1), respectively.",
publisher = "Pergamon-Elsevier Science Ltd, Oxford",
journal = "Spectroscopy Letters",
title = "An application of second-order UV-derivative spectrophotometry for study of solvolysis of a novel fluocinolone acetonide ester",
volume = "75",
number = "2",
pages = "930-935",
doi = "10.1016/j.saa.2009.12.043"
}

Marković, B., Vladimirov, S., Čudina, O., Savić, V.,& Karljiković-Rajić, K.. (2010). An application of second-order UV-derivative spectrophotometry for study of solvolysis of a novel fluocinolone acetonide ester. in Spectroscopy Letters
Pergamon-Elsevier Science Ltd, Oxford., 75(2), 930-935.
https://doi.org/10.1016/j.saa.2009.12.043

Marković B, Vladimirov S, Čudina O, Savić V, Karljiković-Rajić K. An application of second-order UV-derivative spectrophotometry for study of solvolysis of a novel fluocinolone acetonide ester. in Spectroscopy Letters. 2010;75(2):930-935.
doi:10.1016/j.saa.2009.12.043 .

Marković, Bojan, Vladimirov, Sote, Čudina, Olivera, Savić, Vladimir, Karljiković-Rajić, Katarina, "An application of second-order UV-derivative spectrophotometry for study of solvolysis of a novel fluocinolone acetonide ester" in Spectroscopy Letters, 75, no. 2 (2010):930-935,
https://doi.org/10.1016/j.saa.2009.12.043 . .

TY  - JOUR
AU  - Čudina, Olivera
AU  - Brborić, Jasmina
AU  - Janković, I.
AU  - Karljiković-Rajić, Katarina
AU  - Vladimirova, S.
PY  - 2008
UR  - https://farfar.pharmacy.bg.ac.rs/handle/123456789/1090
AB  - In this study, the interaction of valsartan (VAL), an angiotensin II receptor antagonist, with cationic surfactant cetyltrimethylammonium bromide (CTAB) was investigated. The effect of cationic micelles on spectroscopic and acid-base properties of VAL was carried out using UV spectrophotometry at physiological conditions (pH 7.4). The binding of VAL to CTAB micelles implied a shift in drug acidity constant (pK(a)(water) - pK(a)(micelle) = 1.69) proving the great affinity of VAL dianion for the positively charged CTAB micelle surface. To quantify the degree of VAL/CTAB interaction, two constants were calculated by using mathematical models: micelle/water partition coefficient (K-x) and drug/micelle binding constant (K-b). The decrease of K-x with VAL concentration, obtained by using pseudo-phase model, is consistent with an adsorption-like phenomenon. From the dependence of differential absorbance at lambda = 295 nm on CTAB concentration, by using mathematical model that treats the solubilization of VAL dianion as its binding to specific sites in the micelles (Langmuir adsorption isotherm), the binding constant (K-b = (2.50 +/- 10.49) x 10(4) M-1) was obtained. Binding constant VAL/CTAB was also calculated using micellar liquid chromatography (MLC).
PB  - Elsevier Science BV, Amsterdam
T2  - Colloids and Surfaces B: Biointerfaces
T1  - Study of valsartan interaction with micelles as a model system for biomembranes
VL  - 65
IS  - 1
SP  - 80
EP  - 84
DO  - 10.1016/j.colsurfb.2008.03.002
ER  - 

@article{
author = "Čudina, Olivera and Brborić, Jasmina and Janković, I. and Karljiković-Rajić, Katarina and Vladimirova, S.",
year = "2008",
abstract = "In this study, the interaction of valsartan (VAL), an angiotensin II receptor antagonist, with cationic surfactant cetyltrimethylammonium bromide (CTAB) was investigated. The effect of cationic micelles on spectroscopic and acid-base properties of VAL was carried out using UV spectrophotometry at physiological conditions (pH 7.4). The binding of VAL to CTAB micelles implied a shift in drug acidity constant (pK(a)(water) - pK(a)(micelle) = 1.69) proving the great affinity of VAL dianion for the positively charged CTAB micelle surface. To quantify the degree of VAL/CTAB interaction, two constants were calculated by using mathematical models: micelle/water partition coefficient (K-x) and drug/micelle binding constant (K-b). The decrease of K-x with VAL concentration, obtained by using pseudo-phase model, is consistent with an adsorption-like phenomenon. From the dependence of differential absorbance at lambda = 295 nm on CTAB concentration, by using mathematical model that treats the solubilization of VAL dianion as its binding to specific sites in the micelles (Langmuir adsorption isotherm), the binding constant (K-b = (2.50 +/- 10.49) x 10(4) M-1) was obtained. Binding constant VAL/CTAB was also calculated using micellar liquid chromatography (MLC).",
publisher = "Elsevier Science BV, Amsterdam",
journal = "Colloids and Surfaces B: Biointerfaces",
title = "Study of valsartan interaction with micelles as a model system for biomembranes",
volume = "65",
number = "1",
pages = "80-84",
doi = "10.1016/j.colsurfb.2008.03.002"
}

Čudina, O., Brborić, J., Janković, I., Karljiković-Rajić, K.,& Vladimirova, S.. (2008). Study of valsartan interaction with micelles as a model system for biomembranes. in Colloids and Surfaces B: Biointerfaces
Elsevier Science BV, Amsterdam., 65(1), 80-84.
https://doi.org/10.1016/j.colsurfb.2008.03.002

Čudina O, Brborić J, Janković I, Karljiković-Rajić K, Vladimirova S. Study of valsartan interaction with micelles as a model system for biomembranes. in Colloids and Surfaces B: Biointerfaces. 2008;65(1):80-84.
doi:10.1016/j.colsurfb.2008.03.002 .

Čudina, Olivera, Brborić, Jasmina, Janković, I., Karljiković-Rajić, Katarina, Vladimirova, S., "Study of valsartan interaction with micelles as a model system for biomembranes" in Colloids and Surfaces B: Biointerfaces, 65, no. 1 (2008):80-84,
https://doi.org/10.1016/j.colsurfb.2008.03.002 . .

TY  - JOUR
AU  - Injac, Rade
AU  - Mlinarić, Ales
AU  - Đorđević-Milić, Vukosava
AU  - Karljiković-Rajić, Katarina
AU  - Štrukelj, Borut
PY  - 2008
UR  - https://farfar.pharmacy.bg.ac.rs/handle/123456789/1103
AB  - A separation technique for zinc bacitracin, polymyxin B, oxytetracycline and sulfacetamide in animal feedstuffs by micellar electrokinetic capillary chromatography (MEKC) was developed. The running buffer was 20 mmoll(-1) borate, 20 mmoll(-1) phosphate, pH 8.4, containing 20 mmoll(-1) sodium dodecylsulphate and 10% (v/v) methanol. MEKC was performed at 25C; the applied voltage was 25 kV with a running pressure of 10 mbar. Simultaneous UV detection for all analytes was at 215 nm. The method was validated for specificity, accuracy, linearity, precision and robustness. It was shown to be specific, accurate (recoveries were 99.7 +/- 0.3, 99.9 +/- 0.9, 99.8 +/- 1.0 and 99.5 +/- 0.4, respectively, for oxytetracycline-, sulfacetamide-, polymyxin B- and zinc bacitracin-spiked samples of feed for cow, pigs, chicken and cattle), linear over the tested range (correlation coefficients >= 0.9987) and precise (RSDs below 1.8% for each analyte). The method was applied to determine zinc bacitracin, polymyxin B, oxytetracycline and sulfacetamide as additives in animal feed.
PB  - Taylor & Francis Ltd, Abingdon
T2  - Food Additives and Contaminants Part A: Chemistry Analysis Control Exposure & Risk Assessment
T1  - Optimal conditions for determination of zinc bacitracin, polymyxin B, oxytetracycline and sulfacetamide in animal feed by micellar electrokinetic capillary chromatography
VL  - 25
IS  - 4
SP  - 424
EP  - 431
DO  - 10.1080/02652030701584058
ER  - 

@article{
author = "Injac, Rade and Mlinarić, Ales and Đorđević-Milić, Vukosava and Karljiković-Rajić, Katarina and Štrukelj, Borut",
year = "2008",
abstract = "A separation technique for zinc bacitracin, polymyxin B, oxytetracycline and sulfacetamide in animal feedstuffs by micellar electrokinetic capillary chromatography (MEKC) was developed. The running buffer was 20 mmoll(-1) borate, 20 mmoll(-1) phosphate, pH 8.4, containing 20 mmoll(-1) sodium dodecylsulphate and 10% (v/v) methanol. MEKC was performed at 25C; the applied voltage was 25 kV with a running pressure of 10 mbar. Simultaneous UV detection for all analytes was at 215 nm. The method was validated for specificity, accuracy, linearity, precision and robustness. It was shown to be specific, accurate (recoveries were 99.7 +/- 0.3, 99.9 +/- 0.9, 99.8 +/- 1.0 and 99.5 +/- 0.4, respectively, for oxytetracycline-, sulfacetamide-, polymyxin B- and zinc bacitracin-spiked samples of feed for cow, pigs, chicken and cattle), linear over the tested range (correlation coefficients >= 0.9987) and precise (RSDs below 1.8% for each analyte). The method was applied to determine zinc bacitracin, polymyxin B, oxytetracycline and sulfacetamide as additives in animal feed.",
publisher = "Taylor & Francis Ltd, Abingdon",
journal = "Food Additives and Contaminants Part A: Chemistry Analysis Control Exposure & Risk Assessment",
title = "Optimal conditions for determination of zinc bacitracin, polymyxin B, oxytetracycline and sulfacetamide in animal feed by micellar electrokinetic capillary chromatography",
volume = "25",
number = "4",
pages = "424-431",
doi = "10.1080/02652030701584058"
}

Injac, R., Mlinarić, A., Đorđević-Milić, V., Karljiković-Rajić, K.,& Štrukelj, B.. (2008). Optimal conditions for determination of zinc bacitracin, polymyxin B, oxytetracycline and sulfacetamide in animal feed by micellar electrokinetic capillary chromatography. in Food Additives and Contaminants Part A: Chemistry Analysis Control Exposure & Risk Assessment
Taylor & Francis Ltd, Abingdon., 25(4), 424-431.
https://doi.org/10.1080/02652030701584058

Injac R, Mlinarić A, Đorđević-Milić V, Karljiković-Rajić K, Štrukelj B. Optimal conditions for determination of zinc bacitracin, polymyxin B, oxytetracycline and sulfacetamide in animal feed by micellar electrokinetic capillary chromatography. in Food Additives and Contaminants Part A: Chemistry Analysis Control Exposure & Risk Assessment. 2008;25(4):424-431.
doi:10.1080/02652030701584058 .

Injac, Rade, Mlinarić, Ales, Đorđević-Milić, Vukosava, Karljiković-Rajić, Katarina, Štrukelj, Borut, "Optimal conditions for determination of zinc bacitracin, polymyxin B, oxytetracycline and sulfacetamide in animal feed by micellar electrokinetic capillary chromatography" in Food Additives and Contaminants Part A: Chemistry Analysis Control Exposure & Risk Assessment, 25, no. 4 (2008):424-431,
https://doi.org/10.1080/02652030701584058 . .

TY  - JOUR
AU  - Injac, Rade
AU  - Srđenović, Branislava
AU  - Prijatelj, Matevz
AU  - Bošković, Marija
AU  - Karljiković-Rajić, Katarina
AU  - Štrukelj, Borut
PY  - 2008
UR  - https://farfar.pharmacy.bg.ac.rs/handle/123456789/1053
PB  - Preston Publ Inc, Niles
T2  - Journal of Chromatographic Science
T1  - Determination of caffeine and associated compounds in food, beverages, natural products, pharmaceuticals, and cosmetics by micellar electrokinetic capillary chromatography
VL  - 46
IS  - 2
SP  - 137
EP  - 143
DO  - 10.1093/chromsci/46.2.137
ER  - 

@article{
author = "Injac, Rade and Srđenović, Branislava and Prijatelj, Matevz and Bošković, Marija and Karljiković-Rajić, Katarina and Štrukelj, Borut",
year = "2008",
publisher = "Preston Publ Inc, Niles",
journal = "Journal of Chromatographic Science",
title = "Determination of caffeine and associated compounds in food, beverages, natural products, pharmaceuticals, and cosmetics by micellar electrokinetic capillary chromatography",
volume = "46",
number = "2",
pages = "137-143",
doi = "10.1093/chromsci/46.2.137"
}

Injac, R., Srđenović, B., Prijatelj, M., Bošković, M., Karljiković-Rajić, K.,& Štrukelj, B.. (2008). Determination of caffeine and associated compounds in food, beverages, natural products, pharmaceuticals, and cosmetics by micellar electrokinetic capillary chromatography. in Journal of Chromatographic Science
Preston Publ Inc, Niles., 46(2), 137-143.
https://doi.org/10.1093/chromsci/46.2.137

Injac R, Srđenović B, Prijatelj M, Bošković M, Karljiković-Rajić K, Štrukelj B. Determination of caffeine and associated compounds in food, beverages, natural products, pharmaceuticals, and cosmetics by micellar electrokinetic capillary chromatography. in Journal of Chromatographic Science. 2008;46(2):137-143.
doi:10.1093/chromsci/46.2.137 .

Injac, Rade, Srđenović, Branislava, Prijatelj, Matevz, Bošković, Marija, Karljiković-Rajić, Katarina, Štrukelj, Borut, "Determination of caffeine and associated compounds in food, beverages, natural products, pharmaceuticals, and cosmetics by micellar electrokinetic capillary chromatography" in Journal of Chromatographic Science, 46, no. 2 (2008):137-143,
https://doi.org/10.1093/chromsci/46.2.137 . .

TY  - JOUR
AU  - Injac, Rade
AU  - Karljiković-Rajić, Katarina
AU  - Štrukelj, Borut
PY  - 2008
UR  - https://farfar.pharmacy.bg.ac.rs/handle/123456789/1134
AB  - Micellar electrokinetic capillary chromatography (MEKC) has become a popular mode among the several capillary electro-migration techniques. Most drug analysis can be performed by using MEKC because of its wide applicability. Separation of very complex mixtures, determination of drugs in the biological materials, etc., can be successfully achieved by MEKC. This review surveys typical applications of MEKC analysis. Recent advances in MEKC, especially with solid-phase extraction and large-volume sample stacking, are described. Modes of electrokinetic chromatography including MEKC, a separation theory of MEKC, environmental friendly analysis, and selectivity manipulation in MEKC are also briefly mentioned.
AB  - Micelama elektrokinetička kapilarna hromatografija (MEKC) postala je najpopularnija kapilarna elektromigraciona metoda. Na osnovu veoma široke upotrebe metode, većina analiza lekova moguća je uz MEKC. Separacija veoma kompleksnih smeša, određivanje lekova u biološkom materijalu, i analize drugih uzoraka, mogu biti veoma uspešno izvedene upotrebom MEKC tehnike. U okviru ovog preglednog rada prikazana je aplikacija tipičnih MEKC metoda. Noviji pristupi u kombinaciji sa čvrsto-faznom ekstrakcijom i visoko-volumskim injektovanjem su takođe opisani. Teorijski i ekološki pristup, kao i prednosti i nedostatci same metode, prikazani su teorijski i kroz praktične primere.
PB  - Savez hemijskih inženjera, Beograd
T2  - Hemijska industrija
T1  - Application of micellar electrokinetic capillary chromatography for routine analysis of different materials
T1  - Upotreba micelarne elektrokinetičke kapilarne hromatografije u rutinskoj analizi različitih uzoraka
VL  - 62
IS  - 3
SP  - 181
EP  - 190
DO  - 10.2298/HEMIND0803181I
ER  - 

@article{
author = "Injac, Rade and Karljiković-Rajić, Katarina and Štrukelj, Borut",
year = "2008",
abstract = "Micellar electrokinetic capillary chromatography (MEKC) has become a popular mode among the several capillary electro-migration techniques. Most drug analysis can be performed by using MEKC because of its wide applicability. Separation of very complex mixtures, determination of drugs in the biological materials, etc., can be successfully achieved by MEKC. This review surveys typical applications of MEKC analysis. Recent advances in MEKC, especially with solid-phase extraction and large-volume sample stacking, are described. Modes of electrokinetic chromatography including MEKC, a separation theory of MEKC, environmental friendly analysis, and selectivity manipulation in MEKC are also briefly mentioned., Micelama elektrokinetička kapilarna hromatografija (MEKC) postala je najpopularnija kapilarna elektromigraciona metoda. Na osnovu veoma široke upotrebe metode, većina analiza lekova moguća je uz MEKC. Separacija veoma kompleksnih smeša, određivanje lekova u biološkom materijalu, i analize drugih uzoraka, mogu biti veoma uspešno izvedene upotrebom MEKC tehnike. U okviru ovog preglednog rada prikazana je aplikacija tipičnih MEKC metoda. Noviji pristupi u kombinaciji sa čvrsto-faznom ekstrakcijom i visoko-volumskim injektovanjem su takođe opisani. Teorijski i ekološki pristup, kao i prednosti i nedostatci same metode, prikazani su teorijski i kroz praktične primere.",
publisher = "Savez hemijskih inženjera, Beograd",
journal = "Hemijska industrija",
title = "Application of micellar electrokinetic capillary chromatography for routine analysis of different materials, Upotreba micelarne elektrokinetičke kapilarne hromatografije u rutinskoj analizi različitih uzoraka",
volume = "62",
number = "3",
pages = "181-190",
doi = "10.2298/HEMIND0803181I"
}

Injac, R., Karljiković-Rajić, K.,& Štrukelj, B.. (2008). Application of micellar electrokinetic capillary chromatography for routine analysis of different materials. in Hemijska industrija
Savez hemijskih inženjera, Beograd., 62(3), 181-190.
https://doi.org/10.2298/HEMIND0803181I

Injac R, Karljiković-Rajić K, Štrukelj B. Application of micellar electrokinetic capillary chromatography for routine analysis of different materials. in Hemijska industrija. 2008;62(3):181-190.
doi:10.2298/HEMIND0803181I .

Injac, Rade, Karljiković-Rajić, Katarina, Štrukelj, Borut, "Application of micellar electrokinetic capillary chromatography for routine analysis of different materials" in Hemijska industrija, 62, no. 3 (2008):181-190,
https://doi.org/10.2298/HEMIND0803181I . .

TY  - JOUR
AU  - Injac, Rade
AU  - Kac, Javor
AU  - Karljiković-Rajić, Katarina
AU  - Štrukelj, Borut
PY  - 2008
UR  - https://farfar.pharmacy.bg.ac.rs/handle/123456789/1110
AB  - A micellar electrokinetic capillary chromatography was performed at 25 degrees C and 30 kV (under pressure of 15 mbar), with 30 mM berate buffer (pH 9.0), 60 mM sodium dodecysulfate, and 10% (v/v) ethanol as background electrolyte for the determination of sulfamethoxazole and trimethoprim. UV detection was at 205 nm. Recoveries were optimal and acceptable after extraction with ethanol / deionized water (1:1, v/v) for both investigated compounds from laboratory mixtures of standards. The method was shown to be specific, accurate (recoveries were 99.9 +/- 0.4% for sulfamethoxazole and 99.8 +/- 0.3% for trimethoprim), linear over the tested ranges (correlation coefficients >= 0.9990) and precise (RSD below 0.6%). The method was applied to determine sulfamethoxazole and trimethoprim in tablets, powder for cutaneous use and solution for infusion.
PB  - Food & Drug Adminstration, Taipei
T2  - Journal of Food and Drug Analysis
T1  - Optimal conditions for extraction and simultaneous determination of sulfamethoxazole and trimethoprim in pharmaceuticals by micellar electrokinetic capillary chromatography
VL  - 16
IS  - 1
SP  - 18
EP  - 25
UR  - https://hdl.handle.net/21.15107/rcub_farfar_1110
ER  - 

@article{
author = "Injac, Rade and Kac, Javor and Karljiković-Rajić, Katarina and Štrukelj, Borut",
year = "2008",
abstract = "A micellar electrokinetic capillary chromatography was performed at 25 degrees C and 30 kV (under pressure of 15 mbar), with 30 mM berate buffer (pH 9.0), 60 mM sodium dodecysulfate, and 10% (v/v) ethanol as background electrolyte for the determination of sulfamethoxazole and trimethoprim. UV detection was at 205 nm. Recoveries were optimal and acceptable after extraction with ethanol / deionized water (1:1, v/v) for both investigated compounds from laboratory mixtures of standards. The method was shown to be specific, accurate (recoveries were 99.9 +/- 0.4% for sulfamethoxazole and 99.8 +/- 0.3% for trimethoprim), linear over the tested ranges (correlation coefficients >= 0.9990) and precise (RSD below 0.6%). The method was applied to determine sulfamethoxazole and trimethoprim in tablets, powder for cutaneous use and solution for infusion.",
publisher = "Food & Drug Adminstration, Taipei",
journal = "Journal of Food and Drug Analysis",
title = "Optimal conditions for extraction and simultaneous determination of sulfamethoxazole and trimethoprim in pharmaceuticals by micellar electrokinetic capillary chromatography",
volume = "16",
number = "1",
pages = "18-25",
url = "https://hdl.handle.net/21.15107/rcub_farfar_1110"
}

Injac, R., Kac, J., Karljiković-Rajić, K.,& Štrukelj, B.. (2008). Optimal conditions for extraction and simultaneous determination of sulfamethoxazole and trimethoprim in pharmaceuticals by micellar electrokinetic capillary chromatography. in Journal of Food and Drug Analysis
Food & Drug Adminstration, Taipei., 16(1), 18-25.
https://hdl.handle.net/21.15107/rcub_farfar_1110

Injac R, Kac J, Karljiković-Rajić K, Štrukelj B. Optimal conditions for extraction and simultaneous determination of sulfamethoxazole and trimethoprim in pharmaceuticals by micellar electrokinetic capillary chromatography. in Journal of Food and Drug Analysis. 2008;16(1):18-25.
https://hdl.handle.net/21.15107/rcub_farfar_1110 .

Injac, Rade, Kac, Javor, Karljiković-Rajić, Katarina, Štrukelj, Borut, "Optimal conditions for extraction and simultaneous determination of sulfamethoxazole and trimethoprim in pharmaceuticals by micellar electrokinetic capillary chromatography" in Journal of Food and Drug Analysis, 16, no. 1 (2008):18-25,
https://hdl.handle.net/21.15107/rcub_farfar_1110 .

TY  - JOUR
AU  - Injac, Rade
AU  - Karljiković-Rajić, Katarina
AU  - Štrukelj, Borut
PY  - 2008
UR  - https://farfar.pharmacy.bg.ac.rs/handle/123456789/1061
AB  - A novel and simple method has been developed for the determination of doxycycline (DOX) in biological fluids. The method is based on SPE, large-volume sample stacking (LVSS) and MEKC with UV-DAD detection. Six SPE cartridges have been used in investigation for sample clean up and pre-concentration (Supelco (R) LC-8, LC-18, LC-SCX, and LC-WCX, as well as Strata (TM)-X and X-C). DOX was determined on a 56 cm. (effective length 50 cm) x 50 mu m id fused-silica capillary. The BGE was 20 mM borate buffer, pH 9.3, containing 80 mM SDS and 7.5% v/v of methanol (30 s x 50 mbar), and the temperature and voltage were 25 degrees C and 30 kV, respectively. The analytical wavelength was set at 210 nm. Under optimized conditions it is possible to determine DOX in human serum, urine, semen, tears and saliva with recovery of 97.5% (RSD 2.5%). The method was shown to be sensitive (LOD is 1 mu g/L) and precise (intra-day RSD 0.2 and 2.4%; inter-days 0.4 and 3.5% for migration time and peak area, respectively). Results for developed SPE-LVSS-MEKC were compared with LVSS-MEKC method with direct sample injection. The new LVSS-MEKC method is presented as a useful technique for rapid determination without extraction procedure of DOX in human urine and serum, using 80mM of SDS, 10% v/v of methanol and 40 mM borate buffer (pH 9.3; 30 s x 50 mbar; 25 degrees C; 30 kV; 350 nm), but not for the other biological fluids, according to lower sensitivity of the method and because of the sample composition.
PB  - Wiley-VCH Verlag GMBH, Weinheim
T2  - Electrophoresis
T1  - SPE and large-volume sample stacking in MEKC for determination of doxycycline in biological fluids: Comparison of direct injection to SPE-MEKC
VL  - 29
IS  - 21
SP  - 4431
EP  - 4438
DO  - 10.1002/elps.200800339
ER  - 

@article{
author = "Injac, Rade and Karljiković-Rajić, Katarina and Štrukelj, Borut",
year = "2008",
abstract = "A novel and simple method has been developed for the determination of doxycycline (DOX) in biological fluids. The method is based on SPE, large-volume sample stacking (LVSS) and MEKC with UV-DAD detection. Six SPE cartridges have been used in investigation for sample clean up and pre-concentration (Supelco (R) LC-8, LC-18, LC-SCX, and LC-WCX, as well as Strata (TM)-X and X-C). DOX was determined on a 56 cm. (effective length 50 cm) x 50 mu m id fused-silica capillary. The BGE was 20 mM borate buffer, pH 9.3, containing 80 mM SDS and 7.5% v/v of methanol (30 s x 50 mbar), and the temperature and voltage were 25 degrees C and 30 kV, respectively. The analytical wavelength was set at 210 nm. Under optimized conditions it is possible to determine DOX in human serum, urine, semen, tears and saliva with recovery of 97.5% (RSD 2.5%). The method was shown to be sensitive (LOD is 1 mu g/L) and precise (intra-day RSD 0.2 and 2.4%; inter-days 0.4 and 3.5% for migration time and peak area, respectively). Results for developed SPE-LVSS-MEKC were compared with LVSS-MEKC method with direct sample injection. The new LVSS-MEKC method is presented as a useful technique for rapid determination without extraction procedure of DOX in human urine and serum, using 80mM of SDS, 10% v/v of methanol and 40 mM borate buffer (pH 9.3; 30 s x 50 mbar; 25 degrees C; 30 kV; 350 nm), but not for the other biological fluids, according to lower sensitivity of the method and because of the sample composition.",
publisher = "Wiley-VCH Verlag GMBH, Weinheim",
journal = "Electrophoresis",
title = "SPE and large-volume sample stacking in MEKC for determination of doxycycline in biological fluids: Comparison of direct injection to SPE-MEKC",
volume = "29",
number = "21",
pages = "4431-4438",
doi = "10.1002/elps.200800339"
}

Injac, R., Karljiković-Rajić, K.,& Štrukelj, B.. (2008). SPE and large-volume sample stacking in MEKC for determination of doxycycline in biological fluids: Comparison of direct injection to SPE-MEKC. in Electrophoresis
Wiley-VCH Verlag GMBH, Weinheim., 29(21), 4431-4438.
https://doi.org/10.1002/elps.200800339

Injac R, Karljiković-Rajić K, Štrukelj B. SPE and large-volume sample stacking in MEKC for determination of doxycycline in biological fluids: Comparison of direct injection to SPE-MEKC. in Electrophoresis. 2008;29(21):4431-4438.
doi:10.1002/elps.200800339 .

Injac, Rade, Karljiković-Rajić, Katarina, Štrukelj, Borut, "SPE and large-volume sample stacking in MEKC for determination of doxycycline in biological fluids: Comparison of direct injection to SPE-MEKC" in Electrophoresis, 29, no. 21 (2008):4431-4438,
https://doi.org/10.1002/elps.200800339 . .

TY  - CONF
AU  - Čudina, Olivera
AU  - Janković, I.
AU  - Karljiković-Rajić, Katarina
AU  - Vladimirov, S.
PY  - 2006
UR  - https://farfar.pharmacy.bg.ac.rs/handle/123456789/720
PB  - Savez farmaceutskih udruženja Srbije, Beograd
C3  - Arhiv za farmaciju
T1  - An interaction study of valsartan/cationic surfactant using absorption UV spectrophotometry
T1  - Ispitivanje interakcija valsartan/katjonski surfaktant primenom apsorpcione UV spektrofotometrije
VL  - 56
IS  - 5
SP  - 690
EP  - 691
UR  - https://hdl.handle.net/21.15107/rcub_farfar_720
ER  - 

@conference{
author = "Čudina, Olivera and Janković, I. and Karljiković-Rajić, Katarina and Vladimirov, S.",
year = "2006",
publisher = "Savez farmaceutskih udruženja Srbije, Beograd",
journal = "Arhiv za farmaciju",
title = "An interaction study of valsartan/cationic surfactant using absorption UV spectrophotometry, Ispitivanje interakcija valsartan/katjonski surfaktant primenom apsorpcione UV spektrofotometrije",
volume = "56",
number = "5",
pages = "690-691",
url = "https://hdl.handle.net/21.15107/rcub_farfar_720"
}

Čudina, O., Janković, I., Karljiković-Rajić, K.,& Vladimirov, S.. (2006). An interaction study of valsartan/cationic surfactant using absorption UV spectrophotometry. in Arhiv za farmaciju
Savez farmaceutskih udruženja Srbije, Beograd., 56(5), 690-691.
https://hdl.handle.net/21.15107/rcub_farfar_720

Čudina O, Janković I, Karljiković-Rajić K, Vladimirov S. An interaction study of valsartan/cationic surfactant using absorption UV spectrophotometry. in Arhiv za farmaciju. 2006;56(5):690-691.
https://hdl.handle.net/21.15107/rcub_farfar_720 .

Čudina, Olivera, Janković, I., Karljiković-Rajić, Katarina, Vladimirov, S., "An interaction study of valsartan/cationic surfactant using absorption UV spectrophotometry" in Arhiv za farmaciju, 56, no. 5 (2006):690-691,
https://hdl.handle.net/21.15107/rcub_farfar_720 .

TY  - JOUR
AU  - Injac, Rade
AU  - Kac, Javor
AU  - Mlinarić, Ales
AU  - Karljiković-Rajić, Katarina
PY  - 2006
UR  - https://farfar.pharmacy.bg.ac.rs/handle/123456789/825
AB  - An MEKC procedure was developed for the separation of zinc bacitracin (Zn-BC) and nystatin (NYS) in mixtures and in animal feedstuff. The running buffer was 15 mM borate/19 mM phosphate, pH 8.2, containing 20 mM SDS and 10% v/v methanol. Samples were run at 25 degrees C, the applied voltage was 25 IN, and an additional pressure of 5 mbar was applied. Both analytes were detected by LTV simultaneously at 215 nm, Zn-BC alone at 192 and 254 nm, and NYS alone at 305 nm. The method was shown to be specific, accurate (recoveries were 100.0 +/- 0.6% and 100.1 +/- 0.6% for Zn-BC and NYS, respectively), linear over the tested range (correlation coefficients 0.9991 and 0.9994), and precise (RSD below 1.3% for both analytes). The method was applied to determine Zn-BC and NYS as additives in animal feed.
PB  - Wiley-VCH Verlag GMBH, Weinheim
T2  - Journal of Separation Science
T1  - Micellar electrokinetic capillary chromatography determination of zinc bacitracin and nystatin in animal feed
VL  - 29
IS  - 9
SP  - 1288
EP  - 1293
DO  - 10.1002/jssc.200500477
ER  - 

@article{
author = "Injac, Rade and Kac, Javor and Mlinarić, Ales and Karljiković-Rajić, Katarina",
year = "2006",
abstract = "An MEKC procedure was developed for the separation of zinc bacitracin (Zn-BC) and nystatin (NYS) in mixtures and in animal feedstuff. The running buffer was 15 mM borate/19 mM phosphate, pH 8.2, containing 20 mM SDS and 10% v/v methanol. Samples were run at 25 degrees C, the applied voltage was 25 IN, and an additional pressure of 5 mbar was applied. Both analytes were detected by LTV simultaneously at 215 nm, Zn-BC alone at 192 and 254 nm, and NYS alone at 305 nm. The method was shown to be specific, accurate (recoveries were 100.0 +/- 0.6% and 100.1 +/- 0.6% for Zn-BC and NYS, respectively), linear over the tested range (correlation coefficients 0.9991 and 0.9994), and precise (RSD below 1.3% for both analytes). The method was applied to determine Zn-BC and NYS as additives in animal feed.",
publisher = "Wiley-VCH Verlag GMBH, Weinheim",
journal = "Journal of Separation Science",
title = "Micellar electrokinetic capillary chromatography determination of zinc bacitracin and nystatin in animal feed",
volume = "29",
number = "9",
pages = "1288-1293",
doi = "10.1002/jssc.200500477"
}

Injac, R., Kac, J., Mlinarić, A.,& Karljiković-Rajić, K.. (2006). Micellar electrokinetic capillary chromatography determination of zinc bacitracin and nystatin in animal feed. in Journal of Separation Science
Wiley-VCH Verlag GMBH, Weinheim., 29(9), 1288-1293.
https://doi.org/10.1002/jssc.200500477

Injac R, Kac J, Mlinarić A, Karljiković-Rajić K. Micellar electrokinetic capillary chromatography determination of zinc bacitracin and nystatin in animal feed. in Journal of Separation Science. 2006;29(9):1288-1293.
doi:10.1002/jssc.200500477 .

Injac, Rade, Kac, Javor, Mlinarić, Ales, Karljiković-Rajić, Katarina, "Micellar electrokinetic capillary chromatography determination of zinc bacitracin and nystatin in animal feed" in Journal of Separation Science, 29, no. 9 (2006):1288-1293,
https://doi.org/10.1002/jssc.200500477 . .

TY  - JOUR
AU  - Čudina, Olivera
AU  - Karljiković-Rajić, Katarina
AU  - Ruvarac-Bugarcić, I
AU  - Janković, I
PY  - 2005
UR  - https://farfar.pharmacy.bg.ac.rs/handle/123456789/592
AB  - In this study, the interaction of hydrochlorothiazide (HCT), benzothiadiazine diuretic, with cationic surfactant cetyltrimethylammonium bromide (CTAB) was investigated. The effect of cationic micelles on the spectroscopic and acid-base properties of HCT was studied at pH 10.5. The binding of HCT to CTAB micelles implied a shift in drug acidity constant (pK(a)(water) - pK(a)(micelle) =0.46) proving the greater affinity of HCT dianion for the positively charged CTAB micelle surface. From the dependence of differential absorbance at lambda = 355 nm on CTAB concentration, by using mathematical model that treats the solubilization of HCT dianion as its binding to specific sites in the micelles (Langmuir adsorption isotherm), the binding constant K-b = (1.17 +/- 0.16) x 10(4) mol(-1) dm(3) was obtained. By using pseudo-phase model, the partition coefficient between the bulk water and CTAB micelles, K-x, was calculated from both differential absorbance Delta A(355), K-x =(6.18 +/- 0.64) x 10(4) mol((1) dm(3), and first-order derivative amplitude D-1(250.1), K-x =(5.47 +/- 0.56) x 10(4) mol((1) dm(3).
PB  - Elsevier Science BV, Amsterdam
T2  - Colloids and Surfaces A: Physicochemical and Engineering Aspects
T1  - Interaction of hydrochlorothiazide with cationic surfactant micelles of cetyltrimethylammonium bromide
VL  - 256
IS  - 2-3
SP  - 225
EP  - 232
DO  - 10.1016/j.colsurfa.2005.01.023
ER  - 

@article{
author = "Čudina, Olivera and Karljiković-Rajić, Katarina and Ruvarac-Bugarcić, I and Janković, I",
year = "2005",
abstract = "In this study, the interaction of hydrochlorothiazide (HCT), benzothiadiazine diuretic, with cationic surfactant cetyltrimethylammonium bromide (CTAB) was investigated. The effect of cationic micelles on the spectroscopic and acid-base properties of HCT was studied at pH 10.5. The binding of HCT to CTAB micelles implied a shift in drug acidity constant (pK(a)(water) - pK(a)(micelle) =0.46) proving the greater affinity of HCT dianion for the positively charged CTAB micelle surface. From the dependence of differential absorbance at lambda = 355 nm on CTAB concentration, by using mathematical model that treats the solubilization of HCT dianion as its binding to specific sites in the micelles (Langmuir adsorption isotherm), the binding constant K-b = (1.17 +/- 0.16) x 10(4) mol(-1) dm(3) was obtained. By using pseudo-phase model, the partition coefficient between the bulk water and CTAB micelles, K-x, was calculated from both differential absorbance Delta A(355), K-x =(6.18 +/- 0.64) x 10(4) mol((1) dm(3), and first-order derivative amplitude D-1(250.1), K-x =(5.47 +/- 0.56) x 10(4) mol((1) dm(3).",
publisher = "Elsevier Science BV, Amsterdam",
journal = "Colloids and Surfaces A: Physicochemical and Engineering Aspects",
title = "Interaction of hydrochlorothiazide with cationic surfactant micelles of cetyltrimethylammonium bromide",
volume = "256",
number = "2-3",
pages = "225-232",
doi = "10.1016/j.colsurfa.2005.01.023"
}

Čudina, O., Karljiković-Rajić, K., Ruvarac-Bugarcić, I.,& Janković, I.. (2005). Interaction of hydrochlorothiazide with cationic surfactant micelles of cetyltrimethylammonium bromide. in Colloids and Surfaces A: Physicochemical and Engineering Aspects
Elsevier Science BV, Amsterdam., 256(2-3), 225-232.
https://doi.org/10.1016/j.colsurfa.2005.01.023

Čudina O, Karljiković-Rajić K, Ruvarac-Bugarcić I, Janković I. Interaction of hydrochlorothiazide with cationic surfactant micelles of cetyltrimethylammonium bromide. in Colloids and Surfaces A: Physicochemical and Engineering Aspects. 2005;256(2-3):225-232.
doi:10.1016/j.colsurfa.2005.01.023 .

Čudina, Olivera, Karljiković-Rajić, Katarina, Ruvarac-Bugarcić, I, Janković, I, "Interaction of hydrochlorothiazide with cationic surfactant micelles of cetyltrimethylammonium bromide" in Colloids and Surfaces A: Physicochemical and Engineering Aspects, 256, no. 2-3 (2005):225-232,
https://doi.org/10.1016/j.colsurfa.2005.01.023 . .

TY  - JOUR
AU  - Nikolić, N
AU  - Veselinović, D
AU  - Vladimirov, S
AU  - Karljiković-Rajić, Katarina
AU  - Lingeman, H
PY  - 2004
UR  - https://farfar.pharmacy.bg.ac.rs/handle/123456789/534
AB  - Tc-99m(V)-d,l-HM-PAO complex is well-known radiopharmaceutical for regional cerebral blood flow imaging. The proposed modifications in exametazime, hexamethylpropyleneamine oxime (HM-PAO) (4,8-diaza-3,6,6,9-tetramethylundecane-2,10-dione bisoxime) synthesis, for reduction of intermediary reactant diiminebisoxime (DI) (4,8-diaza-3,6,6,9-tetramethylundecane-3,8-diene-2,10-dione bisoxime) concerned two reductants (NaBH4 and KBH4), two solvents (ethanol and 2-propanol), and three mole ratios of reactant/reductants (1:1, 1:1.5, and 1:2). The simultaneous analysis of diastereo-enantiomeric HM-PAO content, as well as the content of starting DI, in different reduction mixtures were pet-formed using chiral ligand-exchange chromatography (CLEC). The separation of the samples of investigated reduction mixtures, obtained in the second step of HM-PAO synthesis, has been accomplished by using an achiral sorbent (RP- 18) and a chiral mobile phase (CMP) containing copper(II) complex with N,N-ditnethyl-L-phenylalanine (L-DM-PhA) as initial complex for CLEC. With 12 different reduction conditions, the obtained ratios of diastereoisomers d,l-HM-PAO: mesa-HM-PAO varied from 69.2:30.8 to 15.9:84.1, in comparison to the reduction in routine synthesis of HM-PAO which gives an equal mixture of diastereoisomers. The ternary mixed complexes formation recorded spectrophotometrically on addition of HM-PAO or DI to the mobile phase with binary complex Cu(L-DM-PhA)(2), due to the evidence of bathochromic shift of 46 nm for lambda(max) with significant difference in absorptivity contributes to separation mechanism.
PB  - Elsevier Science BV, Amsterdam
T2  - Journal of Pharmaceutical and Biomedical Analysis
T1  - Chiral ligand-exchange chromatography as the screening method for proposed modifications in exametazime synthesis to enhance diastereoselectivity
VL  - 34
IS  - 2
SP  - 285
EP  - 293
DO  - 10.1016/S0731-7085(03)00551-X
ER  - 

@article{
author = "Nikolić, N and Veselinović, D and Vladimirov, S and Karljiković-Rajić, Katarina and Lingeman, H",
year = "2004",
abstract = "Tc-99m(V)-d,l-HM-PAO complex is well-known radiopharmaceutical for regional cerebral blood flow imaging. The proposed modifications in exametazime, hexamethylpropyleneamine oxime (HM-PAO) (4,8-diaza-3,6,6,9-tetramethylundecane-2,10-dione bisoxime) synthesis, for reduction of intermediary reactant diiminebisoxime (DI) (4,8-diaza-3,6,6,9-tetramethylundecane-3,8-diene-2,10-dione bisoxime) concerned two reductants (NaBH4 and KBH4), two solvents (ethanol and 2-propanol), and three mole ratios of reactant/reductants (1:1, 1:1.5, and 1:2). The simultaneous analysis of diastereo-enantiomeric HM-PAO content, as well as the content of starting DI, in different reduction mixtures were pet-formed using chiral ligand-exchange chromatography (CLEC). The separation of the samples of investigated reduction mixtures, obtained in the second step of HM-PAO synthesis, has been accomplished by using an achiral sorbent (RP- 18) and a chiral mobile phase (CMP) containing copper(II) complex with N,N-ditnethyl-L-phenylalanine (L-DM-PhA) as initial complex for CLEC. With 12 different reduction conditions, the obtained ratios of diastereoisomers d,l-HM-PAO: mesa-HM-PAO varied from 69.2:30.8 to 15.9:84.1, in comparison to the reduction in routine synthesis of HM-PAO which gives an equal mixture of diastereoisomers. The ternary mixed complexes formation recorded spectrophotometrically on addition of HM-PAO or DI to the mobile phase with binary complex Cu(L-DM-PhA)(2), due to the evidence of bathochromic shift of 46 nm for lambda(max) with significant difference in absorptivity contributes to separation mechanism.",
publisher = "Elsevier Science BV, Amsterdam",
journal = "Journal of Pharmaceutical and Biomedical Analysis",
title = "Chiral ligand-exchange chromatography as the screening method for proposed modifications in exametazime synthesis to enhance diastereoselectivity",
volume = "34",
number = "2",
pages = "285-293",
doi = "10.1016/S0731-7085(03)00551-X"
}

Nikolić, N., Veselinović, D., Vladimirov, S., Karljiković-Rajić, K.,& Lingeman, H.. (2004). Chiral ligand-exchange chromatography as the screening method for proposed modifications in exametazime synthesis to enhance diastereoselectivity. in Journal of Pharmaceutical and Biomedical Analysis
Elsevier Science BV, Amsterdam., 34(2), 285-293.
https://doi.org/10.1016/S0731-7085(03)00551-X

Nikolić N, Veselinović D, Vladimirov S, Karljiković-Rajić K, Lingeman H. Chiral ligand-exchange chromatography as the screening method for proposed modifications in exametazime synthesis to enhance diastereoselectivity. in Journal of Pharmaceutical and Biomedical Analysis. 2004;34(2):285-293.
doi:10.1016/S0731-7085(03)00551-X .

Nikolić, N, Veselinović, D, Vladimirov, S, Karljiković-Rajić, Katarina, Lingeman, H, "Chiral ligand-exchange chromatography as the screening method for proposed modifications in exametazime synthesis to enhance diastereoselectivity" in Journal of Pharmaceutical and Biomedical Analysis, 34, no. 2 (2004):285-293,
https://doi.org/10.1016/S0731-7085(03)00551-X . .

TY  - JOUR
AU  - Agbaba, Danica
AU  - Novović, D
AU  - Karljiković-Rajić, Katarina
AU  - Marinković, Valentina
PY  - 2004
UR  - https://farfar.pharmacy.bg.ac.rs/handle/123456789/525
AB  - A method has been developed for separation of omeprazole and pantoprazole, and their impurities omeprazole sulfone and N-methylpantoprazole, by HPTLC. The mobile phase chloroform-2-propanol-25% ammonia-acetonitrile, 10.8 + 1.2 + 0.3 + 4 (v/v), enables good resolution of large excesses of the drugs from the possible impurities. Regression coefficients (r > 0.998), recovery (90.7-120.0%), and detection limit (0.025-0.05%) were validated and found to be satisfactory. The methods is convenient for quantitative analysis and purity control of the compounds.
PB  - Research Inst Medicinal Plants, Budakalasz
T2  - Journal of Planar Chromatography - Modern TLC
T1  - Densitometric determination of omeprazole, pantoprazole, and their impurities in pharmaceuticals
VL  - 17
IS  - 3
SP  - 169
EP  - 172
DO  - 10.1556/JPC.17.2004.3.2
ER  - 

@article{
author = "Agbaba, Danica and Novović, D and Karljiković-Rajić, Katarina and Marinković, Valentina",
year = "2004",
abstract = "A method has been developed for separation of omeprazole and pantoprazole, and their impurities omeprazole sulfone and N-methylpantoprazole, by HPTLC. The mobile phase chloroform-2-propanol-25% ammonia-acetonitrile, 10.8 + 1.2 + 0.3 + 4 (v/v), enables good resolution of large excesses of the drugs from the possible impurities. Regression coefficients (r > 0.998), recovery (90.7-120.0%), and detection limit (0.025-0.05%) were validated and found to be satisfactory. The methods is convenient for quantitative analysis and purity control of the compounds.",
publisher = "Research Inst Medicinal Plants, Budakalasz",
journal = "Journal of Planar Chromatography - Modern TLC",
title = "Densitometric determination of omeprazole, pantoprazole, and their impurities in pharmaceuticals",
volume = "17",
number = "3",
pages = "169-172",
doi = "10.1556/JPC.17.2004.3.2"
}

Agbaba, D., Novović, D., Karljiković-Rajić, K.,& Marinković, V.. (2004). Densitometric determination of omeprazole, pantoprazole, and their impurities in pharmaceuticals. in Journal of Planar Chromatography - Modern TLC
Research Inst Medicinal Plants, Budakalasz., 17(3), 169-172.
https://doi.org/10.1556/JPC.17.2004.3.2

Agbaba D, Novović D, Karljiković-Rajić K, Marinković V. Densitometric determination of omeprazole, pantoprazole, and their impurities in pharmaceuticals. in Journal of Planar Chromatography - Modern TLC. 2004;17(3):169-172.
doi:10.1556/JPC.17.2004.3.2 .

Agbaba, Danica, Novović, D, Karljiković-Rajić, Katarina, Marinković, Valentina, "Densitometric determination of omeprazole, pantoprazole, and their impurities in pharmaceuticals" in Journal of Planar Chromatography - Modern TLC, 17, no. 3 (2004):169-172,
https://doi.org/10.1556/JPC.17.2004.3.2 . .