title: Simple and sensitive liquid chromatography-tandem mass spectrometry method for determination of the S(+)- and R(-)-enantiomers of baclofen in human plasma and cerebrospinal fluid.
abstract: A simple and sensitive liquid chromatography-tandem mass spectrometry (LC/MS/MS) method to determine the enantiomers of the muscle relaxant baclofen in human plasma and cerebrospinal fluid (CSF) has been developed. A commercially available ultrafiltration membrane is used to prepare the sample. A chiral CROWNPAK CR(+) stationary phase column is then used to perform complete resolution of the S(+)- and R(-)-enantiomers of baclofen. This method was used to analyze human plasma and CSF spiked with baclofen, and the calibration curves for both biologic samples were linear over a concentration range of 0.15-150 ng enantiomer/ml. The lower limit of quantification was 0.15 ng enantiomer/ml in both fluids. Finally, the method was tested with an artificial CSF as an alternative to authentic human CSF. The results showed that no matrix effects and no interfering peaks were observed using this artificial CSF.
authors.affiliation: Drug Metabolism and Physicochemical Property Research Laboratory, Daiichi Pharmaceutical Co. Ltd., 16-13 Kita-Kasai 1-Chome, Edogawa-ku, 134-8630 Tokyo, Japan. gohdatsc@daiichipharm.co.jp
authors.forename: R
authors.initials: R
authors.lastname: Goda
authors.forename: N
authors.initials: N
authors.lastname: Murayama
authors.forename: Y
authors.initials: Y
authors.lastname: Fujimaki
authors.forename: K
authors.initials: K
authors.lastname: Sudo
mesh_terms: D001418:Baclofen / Q000097:blood* / Q000134:cerebrospinal fluid* / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D006801:Humans; D013058:Mass Spectrometry / Q000379:methods*; D009125:Muscle Relaxants, Central / Q000097:blood* / Q000134:cerebrospinal fluid*; D012680:Sensitivity and Specificity; D012996:Solutions; D013048:Specimen Handling / Q000379:methods; D013237:Stereoisomerism
chemical_list: D009125:Muscle Relaxants, Central; D012996:Solutions; D001418:Baclofen