ABSTRACT:
Efavirenz inhibits the activity of viral RNA-directed DNA polymerase (i.e reverse transcriptase). The present work describes a simple, precise and accurate HPTLC method for its estimation as bulk and in tablet dosage form. The chromatographic separation was carried out on precoated silica gel 60F254 aluminium plates using mixture of chloroform: ethyl acetate (9:1 v/v) as mobile phase and densitometric evaluation of spots was carried out at 247 nm using Camag TLC Scanner-3 with win CAT 1.3.4 version software. The experimental parameters like band size of the spot applied, chamber saturation time, solvent front migration, slit width etc. were critically studied and optimum conditions were evolved. The accuracy and reliability of the proposed method was ascertained by evaluating various validation parameters like linearity (1000-5000 ng/spot), precision (intra-day RSD 0.66-1.44%, inter-day RSD 0.87-1.42%), accuracy (98.07 to 99.07 %) and specificity according to ICH guidelines. The proposed method can analyze eight or more formulation units simultaneously on a single plate and provide a faster and cost-effective quality control tool for routine analysis of efavirenz as bulk drug and in tablet formulation.