A UPLC-MS/MS method development and validation for the estimation of sofosbuvir from human plasma

Abstract

Objective: The present work aimed to develop a simple, rapid, specific and precise ultra-performance liquid chromatography-tandem mass spectrophotometric (LC–MS/MS) validated method for quantification of sofosbuvir and internal standard (ISTD) Sofosbuvir-d3 in human plasma. Methods: Samples prepared by employing liquid-liquid extraction (LLE) using 2.5 ml of ethyl acetate. Chromatographic separation was achieved on Gemini 5μ C18, 50 x 4.6 mm column using a mixture of 0.1% (v/v) formic acid in water to methanol at a ratio of 30:70 v/v as the mobile phase. The flow rate was 0.50 ml/min. The LC eluent was split, and approximately 0.1 ml/min was introduced into Tandem mass spectrometer using turbo Ion Spray interface at 325 °C. Quantitation was performed by transitions of 428.35/279.26 (m/z) for sofosbuvir and 431.38/282.37 (m/z) for sofosbuvir-d3. Results: The concentrations of ten working standards showed linearity between 4.063 to 8000.010ng/ml (r2≥ 0.9985). Chromatographic separation was achieved within 2 min. The average extraction recoveries of three quality control concentrations were 75.36% for sofosbuvir and were within the acceptance limits. The coefficient of variation was ≤15% for intra-and inter-batch assays. The %CV of ruggedness ranges 0.35% and 3.09%. The % stability of short term and long term stock solution stability studies was found to be 97.25% and 98.81% respectively. Conclusion: The results obtained for specificity, linearity, accuracy, precision, ruggedness and stability studies were within the acceptance limits. Thus the validated economical method was applied for pharmacokinetic studies of sofosbuvir.