title: Determination of ketamine and metabolites in urine by liquid chromatography-mass spectrometry.
abstract: We have developed an analytical method by using liquid chromatography-mass spectrometry (LC-MS) to determine ketamine and its metabolites in urine. The ionization efficiency between two ionization modes (ESI and APCI) of LC-MS was compared to each other. An easy and simple sample preparation of urine samples was made by passing samples through a 0.22mum PVDF syringe filter. The results indicated that the ionization efficiency of positive APCI mode is better than positive ESI mode for determination of trace ketamines. A wide linearity range of the research is from 5 to 250ngmL(-1) and the detection limits for ketamine, norketamine and dehydronorketamine were 0.95, 0.48 and 0.33ngmL(-1), respectively. The proposed method was tested by analyzing ketamine and metabolites in the urines of volunteers. The concentrations of ketamine, norketamine and dehydronorketamine are ranged of 5.4-131.0, 12.5-74.1 and 22.8-278.9ngmL(-1), respectively and the ketamines concentration profiles in human urine were also determined. The results demonstrate the suitability of liquid chromatography-mass spectrometry approach to analyze trace amount of ketamine and its metabolites in urine.
authors.affiliation: Department of Chemistry, National Chung Hsing University, Taichung, Taiwan, ROC.
authors.forename: Chung-Yu
authors.initials: CY
authors.lastname: Chen
authors.forename: Maw-Rong
authors.initials: MR
authors.lastname: Lee
authors.forename: Fu-Chou
authors.initials: FC
authors.lastname: Cheng
authors.forename: Gong-Jhe
authors.initials: GJ
authors.lastname: Wu