Development of chromatographic methods for analysis of sulfamethoxazole, trimethoprim, their degradation products and preservatives in syrup

Abstract

In this paper the experimental conditions for optimal reversed-phase liquid chromatographic (RP-HPLC) determination of sulfamethoxazole, trimethoprim and preservatives, as well as degradation products of sulfamethoxazole and trimethoprim in syrup were defined. The determination of active compounds and preservatives was carried out on Zorbax Eclipse XDB-C18, 150 mm × 4.6 mm, 5 μm particle size column, mobile phase flow rate was 1.5 mL min-1, and detection at 235 nm for the active compounds and 254 nm for preservatives. Mobile phase A consisted of 150 mL of acetonitrile, 850 mL of water and 1 mL of triethanolamine (pH 5.90 adjusted with diluted acetic acid), while mobile phase B was acetonitrile. The mobile phase ratio was defined by the gradient program. For the determination of degradation products Zorbax Eclipse Plus C18, 100 mm x 4.6 mm, 3.5 μm particle size column was used, the mobile phase flow rate was 0.5 mL min-1 and detection at 210 nm for 3,4,5-trimethoxybenzoic acid and 254 nm for sulfanilic acid and sulfanilamide. Mobile phase A was 50 mM potassium dihydrogenphosphate (pH 5.60 adjusted with a 0.5 mol L-1 potassium hydroxide), while mobile phase B was acetonitrile. The mobile phase ratio was defined by the gradient program. Through the validation of the developed methods their efficiency and reliability is confirmed and consequently the adequacy for the routine control.

U ovom radu prikazano je definisanje eksperimentalnih uslova i optimizacija metoda reverzno-fazne tečne hromatografije (RP-HPLC) za određivanje sulfametoksazola, trimetoprima i konzervanasa, odnosno degradacionih proizvoda sulfametoksazola i trimetoprima u sirupu. Određivanje sadržaja aktivnih komponenti i konzervanasa vršeno je na koloni Zorbax Eclipse XDB-C18, 150 mm × 4,6 mm, 5 μm veličine čestica, protok mobilne faze bio je 1,5 mL min-1, dok je detekcija vršena na 235 nm za aktivne komponente i 254 nm za konzervanse. Mobilna faza A sastojala se od smeše 150 mL acetonitrila, 850 mL vode i 1 mL trietanolamina (pH 5,9 podešen razblaženom sirćetnom kiselinom), a kao mobilna faza B korišćen je acetonitril. Odnos mobilnih faza tokom analize definisan je programom gradijenta. Određivanje sadržaja degradacionih proizvoda vršeno je na koloni Zorbax Eclipse Plus-C18, 100 mm × 4,6 mm, 3,5 μm veličine čestica, uz protok mobilne faze od 0,5 mL min-1 i detekciju na 210 nm za 3,4,5-trimetoksibenzojevu kiselinu i 254 nm za sulfanilnu kiselinu i sulfanilamid. Mobilna faza A bila je 50 mM kalijum-dihidrogenfosfat (pH 5,60 podešen sa 0,5 mol L-1 kalijum-hidroksidom), a mobilna faza B bio je acetonitril. Odnos mobilnih faza tokom analize definisan je programom gradijenta. Validacijom postavljenih metoda potvrđeno je da su efikasne i pouzdane, i kao takve pogodne za rutinsku kontrolu.