title: Direct plasma analysis of drug compounds using monolithic column liquid chromatography and tandem mass spectrometry.
abstract: A monolithic silica column high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method has been developed for the high-speed direct simultaneous determination of a drug discovery compound and its major circulating metabolite (M-72) in rat plasma. This methodology makes use of flow programming and an alkyl-bonded silica rod column for fast macromolecule removal and chromatographic separation without the need for significant sample preparation. The matrix ionization suppression effect on the monolithic column HPLC-MS/MS system was investigated using the postcolumn infusion technique. After 200 plasma injections on a 50 x 4.6 mm monolithic silica column, consistent column efficiency of close to 39,000 theoretical plates/m and reproducible retention times for the analytes were observed. The apparent on-column recoveries of 12 test compounds in rat plasma samples were greater than 90%. The proposed fast direct plasma injection method was tested over a 3-day period with the interday coefficient of variation less than 15% for both analytes.
authors.affiliation: Drug Metabolism and Pharmacokinetics Department, Schering-Plough Research Institute, Kenilworth, New Jersey 07033, USA. yunsheng.hsieh@spcorp.com
authors.forename: Yunsheng
authors.initials: Y
authors.lastname: Hsieh
authors.forename: Ganfeng
authors.initials: G
authors.lastname: Wang
authors.forename: Yuguang
authors.initials: Y
authors.lastname: Wang
authors.forename: Samuel
authors.initials: S
authors.lastname: Chackalamannil
authors.forename: Walter A
authors.initials: WA
authors.lastname: Korfmacher
mesh_terms: D002138:Calibration; D002851:Chromatography, High Pressure Liquid; D003024:Clozapine / Q000032:analysis / Q000378:metabolism; D006801:Humans; D007700:Kinetics; D013058:Mass Spectrometry / Q000379:methods*; D004364:Pharmaceutical Preparations / Q000097:blood*; D015203:Reproducibility of Results
chemical_list: D004364:Pharmaceutical Preparations; D003024:Clozapine