High-performance thin-layer chromatographic determination of diltiazem hydrochloride as bulk drug and in pharmaceutical preparations

A simple, rapid, selective and precise high-performance thin-layer chromatographic method for the analysis of diltiazem hydrochloride both as a bulk drug and in pharmaceuticals is reported. The mobile phase composition was ethyl acetate-methanol-strong ammonia solution (80:10:10, v/v). Densitometric analysis of diltiazem hydrochloride was carried out at 238 nm. The calibration curve of diltiazem hydrochloride in distilled water was linear in the range 40-400 ng. The mean value of correlation coefficient, slope and intercept were 0.997+/-0.0008, 0.0617+/-0.0012 and 7.16+/-0.2562, respectively. The limits of detection and quantitation were 20 ng and 40 ng respectively. The recovery of diltiazem hydrochloride was about 99.5%. The method was utilized to analyse diltiazem hydrochloride from conventional and sustained release tablets in the presence of commonly used excipients. (C) 1998 Elsevier Science B.V.