DEVELOPMENT OF A NEW HIGH-PERFORMANCE THIN LAYER CHROMATOGRAPHIC METHOD FOR QUANTITATIVE ESTIMATION OF LAMIVUDINE AND ZIDOVUDINE IN COMBINED TABLET DOSAGE FORM USING QUALITY BY DESIGN APPROACH

The purpose of this study was to develop a new rapid and robust high-performance thin layer chromatographic (HPTLC) method for separation and quantitation of lamivudine and zidovudine in combined tablet dosage form using a quality by design approach. A Box-Behnken experimental design with response surface methodology was utilized to study the effects of chromatographic chamber saturation time, mobile phase migration distance, and mobile phase composition on R-f value. The R-f value was predicted for lamivudine and zidovudine in between 0.2 and 0.8 to optimize the chromatographic conditions based on the preliminary trials. The optimized chromatographic conditions were 21 min saturation time, 50mm migration distance, and ethyl acetate: hexane: methanol: acetic acid (4:4:2:0.1 v/v/v/v) as a mobile phase. The optimized HPTLC method was validated according to International Conference on Harmonization (ICH) guideline Q2 (R1). The results of study clearly indicate that quality by design concept could be effectively applied to optimize HPTLC method with the minimum number of experimental runs. Developed HPTLC method was successfully applied for routine analysis of lamivudine and zidovudine in combine tablet dosage form.