Quantitative performance of online SPE-LC coupled to Q-Exactive for the analysis of sofosbuvir in human plasma
A quantitative strategy for the analysis of sofosbuvir (SF) in human plasma has been developed with an online solid phase extraction (SPE)-liquid chromatography (LC) coupled with high resolution mass spectrometry (HRMS) system using a MS/MS targeted ion fragmentation scan (t-MS2), targeted-selected ion monitoring (t-SIM) and full MS-SIM (F-SIM) mode. The sample was pretreated automatedly and analyzed within 10 min via an online SPE system equipped with an Oasis®HLB (2.1 × 20 mm, 5 μm) SPE column and LC system with a ZORBAX SB-C18 (4.6 × 250, 5 μm) analytical column. A Q-Exactive hybrid quadrupole-Orbitrap HRMS was utilized for positive identification and quantification. Method detection limits ranged between 0.5 and 2000 ng mL−1 in human plasma for both t-MS2 and t-SIM mode and between 2 and 2000 ng mL−1 for F-SIM mode. In all three modes, the overall intra-day and the inter-day variations were less than 8.07%. The recovery of all three methods was in the range of 92.06–107.20% with RSD% less than 3.90%. The matrix effect of all three methods was in the range of 94.82–101.89% with RSD% less than 7.69%. The optimized two methods (t-MS2 and t-SIM) demonstrated good performance in terms of specificity, lower limit of quantification (LLOQ), linearity, recovery, precision and accuracy.