Stability Indicating HPTLC Method Development and Validation for Simultaneous Estimation of Spironolactone and Hydrochlorothiazide Bulk and in Tablet Dosage Form

Abstract

A method for estimating Spironolactone and Hydrochlorothiazide in both bulk and tablet dose forms simultaneously was devised and validated using a stability-indicating High-Performance Thin-Layer Chromatography (HPTLC) methodology. Using a methanol mobile phase in a 3:7 ratio, the chromatographic separation was accomplished on a silica gel 60 F254 plate. The detecting procedure made use of a wavelength of 270 nm. The method showed remarkable linearity for Spironolactone and Hydrochlorothiazide over concentration ranges of 100-600 µg/mL and 50-300 µg/mL, respectively, with correlation coefficients (r²) of 0.999. Results from precision studies showed that the approach is reproducible, with intra-day RSDs of 0.81% for Spironolactone and 0.92% for Hydrochlorothiazide and inter-day RSDs of 1.09% for Spironolactone and 1.15% for Hydrochlorothiazide. Accuracy was confirmed through recovery studies with values of 98.6% for Spironolactone and 99.2% for Hydrochlorothiazide. The method also effectively separated both drugs from their degradation products, ensuring their applicability for stability testing.