title: Performance evaluation of three liquid chromatography mass spectrometry methods for broad spectrum drug screening.
abstract: BACKGROUND
  Liquid chromatography-mass spectrometry (LC-MS) and tandem LC-MS (LC-MS/MS) are increasingly used in toxicology laboratories as a complementary method to gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-ultraviolet detection (LC-UV) for comprehensive drug screening (CDS). This study was designed to characterize the sensitivity and specificity of three LC-MS(/MS) vendor-supplied methods for targeted CDS and identify the current limitations associated with the use of these technologies.
  
  
  METHODS
  Five methods for broad spectrum CDS, including LC-UV (REMEDi), full scan GC-MS, LC-MS (ZQ-Mass Detector with MassLynx-software), LC-QTRAP-MS/MS (3200-QTRAP with Cliquid-software) and LC-LIT-MS/MS (LXQ Linear Ion Trap with ToxID-software) were evaluated based on their ability to detect drugs in 48 patient urine samples.
  
  
  RESULTS
  The tandem MS methods identified 15% more drugs than the single stage MS or LC-UV methods. Use of two broad spectrum screening methods identified more drugs than any single system alone. False negatives and false positives generated by the LC-MS(/MS) software programs were identified upon manual review of the raw data.
  
  
  CONCLUSIONS
  The LC-MS/MS methods detected a broader menu of drugs; however, it is essential to establish manual data review criteria for all LC-MS(/MS) drug screening methods. Use of an EI-GC-MS and ESI-LC-MS/MS combination for targeted CDS may be optimal due to the complementary nature of the chromatographic and ionization techniques.
authors.affiliation: Department of Laboratory Medicine, University of California San Francisco, San Francisco, CA, USA. kara.lynch@ucsf.edu
authors.forename: Kara L
authors.initials: KL
authors.lastname: Lynch
authors.forename: Autumn R
authors.initials: AR
authors.lastname: Breaud
authors.forename: Hilde
authors.initials: H
authors.lastname: Vandenberghe
authors.forename: Alan H B
authors.initials: AH
authors.lastname: Wu
authors.forename: William
authors.initials: W
authors.lastname: Clarke
mesh_terms: D002853:Chromatography, Liquid / Q000379:methods* / Q000592:standards; D006801:Humans; D004364:Pharmaceutical Preparations / Q000652:urine*; D012984:Software; D015813:Substance Abuse Detection / Q000379:methods*; D053719:Tandem Mass Spectrometry / Q000379:methods* / Q000592:standards
chemical_list: D004364:Pharmaceutical Preparations