LAUSR

TQ-B3203 is a new topoisomerase I inhibitor derived from camptothecin. In this paper, a simple and reliable ultra high performance liquid chromatography-tandem mass spectrometric method was developed and validated for determination of TQ-B3203 in human plasma with TQ-B3203-d8 used as the internal standard. Bis(p-nitrophenyl)phosphate (2 mol/L) was added to ensure the stability of TQ-B3203 in human plasma. Plasma samples were protein precipitated by methanol and processed samples were chromatographed on an AQUITY BEH C8 column (50 × 2.1 mm, i.d. 1.7 μm) with acetonitrile and water (0.1% formic acid) as the mobile phase. The calibration curves showed good linearity (R≥0.99) over the concentration range of 0.5-500 ng/mL. Within- and between-run precision were ≤5.8% and the accuracy was within the range of -8.3% to 14.0%. This method was further successfully applied to a pharmacokinetic study of TQ-B3203 in Chinese advanced solid cancer patients after administration of TQ-B3203 liposome injection. This article is protected by copyright. All rights reserved.