title: HPLC determination of ketamine, norketamine, and dehydronorketamine in plasma with a high-purity reversed-phase sorbent.
abstract: We developed an isocratic, selective, and very sensitive HPLC method for the determination of ketamine and its two main metabolites in plasma. The compounds were extracted from plasma by a liquid-liquid extraction with a dichloromethane:ethyl acetate mixture followed by an acidic back-extraction. Separation was achieved on a new stationary phase, Purospher RP-18 endcapped, with a mobile phase containing acetonitrile:0.03 mol/L phosphate buffer (23:77 by vol) adjusted to pH 7.2. Because of the high column efficiency and the significant improvement of peak symmetry, the quantification limit could be down to 5 micrograms/L for ketamine and norketamine (NK). The intraday and interday CVs ranged from 1.7% to 5.8% and 3.1% to 10.2% for all compounds respectively. The method is sensitive enough for monitoring ketamine, NK, and dehydroketamine in plasma during pharmacokinetic studies after an intravenous bolus of a low dose of ketamine.
authors.affiliation: Université Claude Bernard Lyon 1, Département de Pharmacie Clinique, de Pharmacocinétique et d'Evaluation du Médicament, France.
authors.forename: S
authors.initials: S
authors.lastname: Bolze
authors.forename: R
authors.initials: R
authors.lastname: Boulieu
mesh_terms: D000085:Acetates; D002138:Calibration; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D006801:Humans; D007202:Indicators and Reagents; D007649:Ketamine / Q000031:analogs & derivatives* / Q000097:blood*; D008752:Methylene Chloride; D012680:Sensitivity and Specificity; D013993:Tilidine / Q000031:analogs & derivatives
chemical_list: D000085:Acetates; D007202:Indicators and Reagents; C033420:5,6-dehydronorketamine; D008752:Methylene Chloride; D007649:Ketamine; C062490:nortilidine; C007650:ethyl acetate; D013993:Tilidine; C033419:norketamine