Novel NP and RP-HPTLC in Praxis for Simultaneous Estimation of Chlorthalidone and Cilnidipine in Bulk and Pharmaceutical Formulation

Abstract

Two novel, simple, accurate and reliable High-Performance Thin-Layer Chromatographic (HPTLC) methods for simultaneous analysis of Chlorthalidone (CHL) and Cilnidipine (CIL) in bulk and tablet formulation have been developed and validated. The first method was normal phase chromatography performed on precoated silica gel F254 TLC plate, with toluene: ethyl acetate: methanol 3.2:1.3:0.5 (v/v/v) as a mobile phase. The second method was reversed phase chromatography on RP-18 Silica gel F254 S TLC plates, with methanol: water 3.2:1.8 (v/v) as mobile phase. HPTLC quantitation of CHL and CIL was done by TLC-densitometry at 275 nm. The quantitation by HPTLC method was performed over the concentration range of 250-1500 ng/band for CHL and 200-1200 ng/band for CIL in both methods. The HPTLC method resulted into a compact and well resolved band for CHL and CIL at retention factor (Rf) of 0.34 ± 0.02 and 0.79 ± 0.02 for NP-HPTLC and 0.24 ± 0.02 and 0.81 ± 0.02 RP-HPTLC, respectively. Linear regression analysis data for calibration of HPTLC method represented a good linear relationship with regression coefficient: r2> 0.99 for both methods. The developed methods were validated for precision, robustness, ruggedness, accuracy, sensitivity as per ICH guidelines. Further, the developed method was used for the simultaneous estimation of CHL and CIL in tablets and results found to be in good agreement with label claim.