title: Determination of hair ketamine cut-off value from Hong Kong ketamine users by LC-MS/MS analysis.
abstract: Ketamine is one of the most frequent abused drugs in Hong Kong and South-East Asia, and the cases of ketamine abused have been reported worldwide. Hair has been commonly used as a specimen for the proof of chronic drug abused because of its non-invasiveness and long detection windows. The determinations of ketamine in hair with varieties of state-of-the-art instruments and detection methods have been developed in the past decade; however, the cut-off value for ketamine abuser has not been developed according to the international guidelines. The aim of this study is to propose a cut-off value for ketamine in hair by analyzing ketamine and its metabolite norketamine by LC-MS/MS method in a population of ketamine users in Hong Kong. The limit of detection (LOD) and limit of quantification (LOQ) for ketamine and norketamine were 20pg/mg and 100pg/mg, respectively. From 977 ketamine abusers, the cut-off value for ketamine in hair was proposed to be 400pg/mg of hair. This proposed cut-off value is the concentration of hair ketamine when over 90% of samples are being detected with the presence of norketamine, which is a proof of ketamine abuse. This value could be applied as a screening or occupational cut-off for reference.
authors.affiliation: Division of Life Science and Center for Chinese Medicine, Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay Road, Hong Kong, Hong Kong, China.
authors.forename: K Wing
authors.initials: KW
authors.lastname: Leung
authors.affiliation: Division of Life Science and Center for Chinese Medicine, Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay Road, Hong Kong, Hong Kong, China.
authors.forename: Zack C F
authors.initials: ZC
authors.lastname: Wong
authors.affiliation: Division of Life Science and Center for Chinese Medicine, Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay Road, Hong Kong, Hong Kong, China.
authors.forename: Janet Y M
authors.initials: JY
authors.lastname: Ho
authors.affiliation: Division of Life Science and Center for Chinese Medicine, Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay Road, Hong Kong, Hong Kong, China.
authors.forename: Ada W S
authors.initials: AW
authors.lastname: Yip
authors.affiliation: Division of Life Science and Center for Chinese Medicine, Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay Road, Hong Kong, Hong Kong, China.
authors.forename: Jenny S C
authors.initials: JS
authors.lastname: Ng
authors.affiliation: Division of Life Science and Center for Chinese Medicine, Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay Road, Hong Kong, Hong Kong, China.
authors.forename: Stanley P H
authors.initials: SP
authors.lastname: Ip
authors.affiliation: Division of Life Science and Center for Chinese Medicine, Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay Road, Hong Kong, Hong Kong, China.
authors.forename: Winki Y Y
authors.initials: WY
authors.lastname: Ng
authors.affiliation: Division of Life Science and Center for Chinese Medicine, Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay Road, Hong Kong, Hong Kong, China.
authors.forename: Karen K L
authors.initials: KK
authors.lastname: Ho
authors.affiliation: Division of Life Science and Center for Chinese Medicine, Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay Road, Hong Kong, Hong Kong, China.
authors.forename: Ran
authors.initials: R
authors.lastname: Duan
authors.affiliation: Jiangsu Key Laboratory for High Technology Research of TCM Formulae and Jiangsu Collaborative Innovation Center of Chinese Medicinal Resources Industrialization, Nanjing University of Chinese Medicine, Nanjing, Jiangsu Province, China.
authors.forename: Kevin Y
authors.initials: KY
authors.lastname: Zhu
authors.affiliation: Division of Life Science and Center for Chinese Medicine, Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay Road, Hong Kong, Hong Kong, China. Electronic address: botsim@ust.hk.
authors.forename: Karl W K
authors.initials: KW
authors.lastname: Tsim
mesh_terms: D000293:Adolescent; D000328:Adult; D002853:Chromatography, Liquid; D005260:Female; D006197:Hair; D006723:Hong Kong; D006801:Humans; D013287:Illicit Drugs / Q000032:analysis*; D007649:Ketamine / Q000032:analysis*; D008297:Male; D015203:Reproducibility of Results; D053719:Tandem Mass Spectrometry; D055815:Young Adult
chemical_list: D013287:Illicit Drugs; D007649:Ketamine
keywords: Cut-off; Drug abuse; Hair; Ketamine; LC–MS