Приказ основних података о документу
Protolytic equilibria in homogeneous and heterogeneous aqueous systems of methyl- and propylparaben and influence of β-cyclodextrin on pKa values
Protolitičke ravnoteže u homogenim i heterogenim vodenim sistemima metil- i propilparabena i uticaj β -ciklodekstrina na pKa vrednosti
dc.creator | Popović, Gordana | |
dc.creator | Čakar, Mira | |
dc.date.accessioned | 2019-09-02T10:58:55Z | |
dc.date.available | 2019-09-02T10:58:55Z | |
dc.date.issued | 2004 | |
dc.identifier.issn | 0004-1963 | |
dc.identifier.uri | https://farfar.pharmacy.bg.ac.rs/handle/123456789/512 | |
dc.description.abstract | Acidity constants (Ka) and intrinsic hydrosolubility (Ks0) of two parabens, methylparaben and propylparaben, were spectrophotometrically determined at 25oC and a constant ionic strength of I=0.1 M (NaCl). Based on the determined equilibrium constants Ks0 and Ka, equilibrium constant Ks1 in heterogeneous system of methyl-and propylparaben was calculated. Solubility of the two parabens as a function of solution acidity was calculated applying the equation: s1 s0 3 [ ] S [H O ] K K + = + In addition, the effects of varying β-cyclodextrin concentrations on pKa values of the two parabens were examined. The results showed that β-CD influenced absorption spectra of the parabens (a decreased absorptivity and a bathochromic shift of the absorption maxima), but their pKa values remained almost unchanged. | en |
dc.description.abstract | Spektrofotometrijski su određene kiselinske konstante (Ka) i osnovna rastvorljivost (Ks0) u vodi metilparabena i propilparabena. Određivanja su vršena na temperaturi od 25 oC i pri konstantnoj jonskoj sili I=0.1 M (NaCl). Na osnovu određenih ravnotežnih konstanti Ks0 i Ka izračunata je ravnotežna konstanta Ks1 u heterogenom sistemu parabena. Rastvorljivost parabena u funkciji kiselosti rastvora izračunata je primenom jednačine 1 0 3 [ ] [ ] s s K S K H O+ = + Pored toga, ispitan je uticaj različitih koncentracija β-ciklodekstrina na pKa vrednosti datih parabena. | sr |
dc.publisher | Savez farmaceutskih udruženja Srbije, Beograd | |
dc.rights | openAccess | |
dc.rights.uri | https://creativecommons.org/licenses/by-sa/4.0/ | |
dc.source | Arhiv za farmaciju | |
dc.subject | methylparaben | en |
dc.subject | propylparaben | en |
dc.subject | solubility | en |
dc.subject | acidity constant | en |
dc.subject | metilparaben | sr |
dc.subject | propilparaben | sr |
dc.subject | rastvorljivost | sr |
dc.subject | kiselinska konstanta | sr |
dc.title | Protolytic equilibria in homogeneous and heterogeneous aqueous systems of methyl- and propylparaben and influence of β-cyclodextrin on pKa values | en |
dc.title | Protolitičke ravnoteže u homogenim i heterogenim vodenim sistemima metil- i propilparabena i uticaj β -ciklodekstrina na pKa vrednosti | sr |
dc.type | article | |
dc.rights.license | BY-SA | |
dcterms.abstract | Чакар, Мира; Поповић, Гордана; Протолитичке равнотеже у хомогеним и хетерогеним воденим системима метил- и пропилпарабена и утицај β -циклодекстрина на пКа вредности; Протолитичке равнотеже у хомогеним и хетерогеним воденим системима метил- и пропилпарабена и утицај β -циклодекстрина на пКа вредности; | |
dc.citation.volume | 54 | |
dc.citation.issue | 5 | |
dc.citation.spage | 601 | |
dc.citation.epage | 611 | |
dc.citation.other | 54(5): 601-611 | |
dc.identifier.fulltext | https://farfar.pharmacy.bg.ac.rs//bitstream/id/2033/510.pdf | |
dc.identifier.rcub | https://hdl.handle.net/21.15107/rcub_farfar_512 | |
dc.type.version | publishedVersion |