[Determination of ropivacaine in human serum by reversed-phase high performance liquid chromatography]

A simple and rapid reversed-phase high performance liquid chromatographic method was developed for the determination of ropivacaine. The sample was treated by the addition of bupivacaine as an internal standard, extraction with dichloromethane, and drying by N2. Then the residue dissolved in the mobile phase and 40 microL were injected into the chromatographic system with a mobile phase of 0.01 mol.L-1 KH2PO4 (pH 3.0)-CH3CN(84:16, volume ratio). The detection wavelength was 210 nm. The retention times of ropivacaine and the internal standard were 5.5 min and 10.5 min respectively. The detection limit was 0.025 mg.L-1. The linear range was from 0.05 mg.L-1 to 2.50 mg.L-1 with r of 0.9997. The average recovery was 104.1% with the intra-day and inter-day RSDs of 3.42% and 6.27% respectively. The results showed that it is a simple, rapid and stable method for drug monitoring in clinical research.