Stability can be defined as the capacity of a drug substance or drug product to sus- tain its identity, strength, quality, and purity throughout the retest or expiration period (1). Stability testing of an active substance or finished product provides evidence of the quality of a drug substance or drug product to remain acceptable up to the stated period under storage conditions stated on the label. The International Conference on Harmoni- zation (ICH) guidelines Q1A (R2) require the use of a validated stability-indicating assay method (SIAM) for stability testing of a drug substance or product (2). It also empha- 13 Acta Pharm. 60 (2010) 13–24 Original research paper 10.2478/v10007-010-0010-2 RP-HPLC-DAD method for determination of olmesartan medoxomil in bulk and tablets exposed to forced conditions RITESH N. SHARMA SHYAM S. PANCHOLI S. K. Patel College of Pharmaceutical Education and Research, Ganpat University, Kherva-382711 Gujarat, India Accepted January 14, 2010 A simple, sensitive and precise RP-HPLC-DAD method was developed and validated for the determination of ol- mesartan medoxomil (AT-II receptor blocker) in the pre- sence of its degradation products. Olmesartan medoxo- mil and all the degradation products were resolved on a C 18 column with the mobile phase composed of metha- nol, acetonitrile and water (60:15:25, V/V/V , pH 3.5 by orthophosphoric acid) at 260 nm using a photodiode ar- ray detector. The method was linear over the concentra- tion range of 1–18 mg mL –1 and precise with RSD < 1 % in intra- and inter-day study. Excellent recoveries of 99.3 ± 0.9 to 100.8 ± 1.2 % proved the accuracy of the method. Developed method was specific, as indicated by chroma- tographic resolution > 2.0 for each peak and sensitive with LOD 0.03 mg mL -1 and LOQ 0.1 mg mL –1 . The method was used to study the drug degradation behavior under forc- ed conditions. Four degradation products (DP-I, II, III, IV) were formed during the degradation study in 0.1 mol L –1 HCl whereas only DP-I, II and III were formed in water, 0.01 mol L –1 NaOH and 3 % H 2 O 2 . No significant ther- mal or photolytic degradation was observed in solid drug. The method was applied successfully for the assay of ol- mesartan medoxomil in the tablet dosage form. Keywords: olmesartan medoxomil, forced degradation, high performance liquid chromatography, stability * Correspondence; e-mail: riteshn.sharma@gmail.com Unauthenticated Download Date | 11/2/16 4:28 AM