DEVELOPMENT AND VALIDATION OF STABILITY INDICATING HPTLC METHOD FOR SIMULTANEOUS ESTIMATION OF LAMIVUDINE AND DOLUTEGRAVIR SODIUM IN BULK AND PHARMACEUTICAL DOSAGE FORMULATION

A sensitive, accurate, and precise stability-indicating HPTLC method has been developed for the simultaneous estimation of lamivudine (LMV) and dolutegravir sodium (DOL) in bulk and pharmaceutical dosage formulation. The method employed chloroform: methanol: toluene formic acid (8:2:2:0.2 v/v/v/v) as a mobile phase and silica gel G 60 F254 TLC plates as stationary phase. Chromatographic detection was performed at 271 nm. The R_f Value of LMV and DOL was found to be 0.38 ± 0.02 and 0.62 ± 0.02 respectively. The method was validated in compliance with ICH Guideline for linearity, limit of detection (LOD), limit of quantification (LOQ), precision, specificity, accuracy and robustness. The linear regression analysis shown good linear relationship over the concentration range of 120 – 720 ng/spot for LMV (R² = 0.9994) and 20 – 120 ng /spot for DOL sodium (r² = 0.999). The LOD of LMV and DOL was found to be 8.86 ng/spot and 2.92 ng/spot respectively. The LOQ of LMV and DOL was found to be 26.5 ng/spot and 8.74 ng/spot respectively. The % recovery was calculated and found to be 98.83-101.27% for LMV and 98.95 – 100.97% for DOL respectively. LMV and DOL were subjected to acidic, alkaline, oxidative, neutral and thermal degradation conditions. The degradation products obtained were well resolved from the pure drugs with significantly different R_f values.