High-Performance Thin-Layer Chromatographic method for Simultaneous Determination of Some Angiotensin II Receptor Antagonists with Amlodipine in spiked human plasma with UV Detection

A simple, sensitive, precise, and cost-effective high-performance thin-layer chromatographic (HPTLC) method has been developed and validated for the simultaneous determination of Amlodipine (AML) and some Angiotensin II Receptor Antagonist (AIIRA) drugs, including Olmesartan (OLM), Telmisartan (TLM), Candesartan (CAN), Losartan (LOS), and Irbesartan (IRB), in spiked human plasma. The HPTLC analysis utilized a mobile phase consisting of toluene: ethyl acetate: methanol: acetone: acetic acid (6:1.5:1:0.5:1, v/v/v/v/v) on an aluminum-backed layer of silica gel 60 F254. AML demonstrated a linear relationship within the range of 60–600 ng/band, while the AIIRA drugs (OLM, TLM, CAN, LOS, IRB) showed linearity within the range of 90–900 ng/band. The proposed method exhibited good linearity, with correlation coefficients (r) ranging from 0.9939 to 0.9998 for all five studied mixtures. The method was validated according to International Council for Harmonization (ICH) guidelines for linearity, accuracy, precision, robustness, and detection and quantitation limits. AML and the investigated AIIRA drugs were successfully detected and quantified in both bulk drug and plasma samples, yielding high recovery percentages and low standard deviation values.