Development and validation of stability indicating high-performance thin-layer chromatographic method for estimation of Rifapentine in pharmaceutical formulation

A simple, accurate, and precise method is described for stability indicating a high-performance thin-layer chromatographic (HPTLC) method for development and validation in the pharmaceutical dosage form. The method was based on HPTLC separation of the drug by measurement of the spot at 478 nm. Separation was carried out on silica gel 60GF254 by using mobile phase methanol:toluene:acetic acid (3:7:0.1, v/v/v). The linearity range was between 500-3000 ng/spot with a coefficient of determination 0.999, respectively. The retardation value found was 0.55 +/- 0.02 and the % recovery was found to be 100.610 +/- 0.035%-101.0178 +/- 0.035%. The limit of detection value for Rifapentine was 92.901 ng/spot and the limit of quantitation for Rifapentine was found to be 281.52 ng/spot. Forced degradation studies were carried out under various conditions. In acidic conditions, the % degradation was found to be 20.07%. In alkaline and oxidative conditions, the % degradation was found to be 61.27% and 11.12%. Photolytic and thermal conditions the % degradation was found to be 49.75% and 8.35%. Maximum degradation was found in alkaline condition with 61.27%, an assay for the marketed formulation was carried out and the amount of drug was found to be 149 +/- 0.05 mg with a % of 99.25% +/- 0.005%.