Microanalysis of propofol in human serum by semi-microcolumn high-performance liquid chromatography with UV detection and solid-phase extraction

Objective: To develop a simple analytical method for monitoring the low ser um levels of propofol found when administered for the sedation of patients in the intensive care unit (ICU). Methods: A high-performance liquid chromatographic method (HPLC) was used w ith UV detection. Solid-phase extraction (SPE) cartridges and a semi-microc olumn (TSK gel ODS-80Ts, 2.0 mm i.d. x 25 cm, 5 mum) were used to improve s ensitivity. Propofol in the eluate obtained from the SPE cartridge was conc entrated to about five times the initial concentration. Results: The sensitivity using the semi-microcolumn was amplified by about three-fold. The assay showed a good linearity with a quantification limit 2 0 ng/mL. Intra- and inter-assay coefficients of variation were less than 2. 2% and 10.0%, respectively. The mean recoveries ranged from 97.6 to 109.5%. Conclusion: The HPLC method described should be useful for measuring the lo w serum propofol levels found when the drug is used for ICU sedation.