Abstract: A microemulsion liquid chromatographic (MELC) method was developed for the determination of propofol in human plasma. The assay was performed on a Hypersil BDS C18 column, and the effects of each component in the microemulsion mobile phase on the elution were investigated. The optimized microemulsion mobile phase consisted of 0.5% acetic acid containing 3.0% sodium dodecylsulfate, 0.8% n-heptane, 6.0% n-butanol. The flow rate was 1.0 mL/min, and the separation was operated at ambient temperature. The fluorescence excitation and emission wavelengths were 274 nm and 312 nm, respectively. The plasma samples were diluted with the mobile phase and centrifuged before injection. The calibration curve of propofol was linear within the range of 0.25~10 μg/mL. The method recoveries were (98.2±1.9)%－(104.6±2.2)%. The intra-day relative standard deviations (RSDs) of peak area were 1.42%~2.43%, and the inter-day RSDs were 2.75%~4.79%. The method is simple and reproducible. It can be used for the determination of propofol in human plasma.

Key words: human plasma, propofol, fluorescence detection, microemulsion liquid chromatography (MELC)