Development and Validation of HPTLC Method for Simultaneous Estimation of Metolazone and Spironolactone in Bulk Drug and Pharmaceutical Dosage Form

Abstract

A simple, precise and accurate HPTLC method has been developed for the simultaneous analysis of Metolazone and Spironolactone in bulk drugs and tablet formulation. Chromatographic separation was carried out on Merck HPTLC aluminium plates of Silica gel 60 F254, using n-propanol : triethylamine (7:3 v/v) as the mobile phase. HPTLC separation of the two drugs followed by densitometric measurement was performed in the absorbance mode at 240 nm. The drugs were resolved with R f values of 0.60 and 0.69 for Metolazone and Spironolactone respectively. The linear regression analysis data for the calibration plots showed good linear relationship with r value 0.99886 and 0.99862 for Metolazone and Spironolactone, respectively in the concentration range of 300 -700 ng/spot for Metolazone and 300-700 ng/spot for Spironolactone. The method was validated following the ICH guidelines in terms of accuracy, precision, specificity and robustness. The limit of detection and quantitation were 200 and 600 ng/spot respectively for Metolazone and 200 and 600 ng/spot for Spironolactone. The proposed developed and validated HPTLC method can be utilised for identification and quantitative analysis of Metolazone and Spironolactone in bulk drugs and pharmaceutical dosage form.