A Novel Simultaneous Estimation of Sofosbuvir and Velpatasvir in Human Plasma by Liquid Chromatography Tandem-Mass Spectrometry after Protein Precipitation Method

Abstract

Objective: The aim of the present work is to achieve a novel highly sensitive chromatographic method for the simultaneous determination of hepatitis C agents, sofosbuvir and velpatasvir from human plasma using ritonavir as an internal standard. Methods: Chromatographic separation was achieved using Hypersil C18 column (50mm x 4.6mm, 3μm) with an isocratic elution mode using the mobile phase composition 10 mM ammonium formate buffer (pH 5.0): acetonitrile (20:80 v/v) pumped at a flow rate of 0.5 ml/min. The detection was carried out by tandem mass spectrometry using Multiple Reaction Monitoring (MRM) positive Electrospray Ionization (ESI) with proton adducts at m/z 530.10 > 243.10, 883.40 > 114.0 and 721.25 > 197.0. Results: The method validated as per USFDA guidelines with respect to linearity, accuracy, and precision was found to be acceptable over the concentration range of 0.2–2000 ng/ml and 5-2000 ng/ml for sofosbuvir and velpatasvir respectively and the method was found to be highly sensitive and selective. Conclusion: The developed tandem mass spectrometric method is robust and can be applied for the monitoring of plasma levels of the analyzed drug in preclinical and clinical pharmacokinetic studies.