Abstrakt: |
Tioconazole (TCN) (anti fungal) is commonly co-formulated with tinidazole (TND) (antiprotozoal), hydrocortisone acetate (HYD) (anti infalmmatory) and benzyl alcohol (BZL) (preservative) in different pharmaceutical preparations. Tioconazole has three related impurities namely; tioconazole related impurities A, B and C (TCN-RA), (TCN-RB) and (TCN-RC), respectively. As the main purpose of a test for related substances is to control degradation impurities and to limit impurities arising during the synthesis of active ingredients and on the other hand, high efficiency and less elution are the basic requirements of high-speed chromatographic separation. So, two simple, precise, and accurate reversed-phase HPLC-UV and UPLC-DAD methods have been developed and compared for simultaneous estimation of TND, BZL, HYD and TCN in bulk and pharmaceutical formulations in the presence of TCN related impurities. A Eurospher C18 (250 mm × 4.6 mm, 5 μm) for HPLC method and an Eclipse plus C18 (100 × 2.1 mm, 1.7 μm) for UPLC method were used. An isocratic mobile phase consisted of 20 mM anhydrous KH2PO4(containing 0.2% TEAv/v), pH adjusted to 6 with orthophosphoric acid: acetonitrile, (25:75,v/v) for HPLC method and a gradient mobile phase of 20 mM anhydrous KH2PO4(containing 0.2% TEAv/v), pH adjusted to 6 with orthophosphoric acid and acetonitrile mixed in different proportions for UPLC method, were prepared. Flow rate was set at 1.0 mL min-1and 0.3 mL min-1for HPLC and UPLC methods, respectively and the detection was performed for both methods at 295 nm, 210 nm, 245 nm and 225 nm for TND, BZL, HYD and TCN and its related impurities, respectively. The propsed UPLC-DAD method had advantages, of being economic on the large scale with relatively much satisfactory results for linearity, sensitivity and specificity. The two proposed methods are applicable for the purity assessment of TCN in bulk, vaginal tablets and creams. [ABSTRACT FROM PUBLISHER] |