title: Sulfonium salts as derivatizing agents. 3. Quantitation of the cocaine metabolite benzoylecgonine in urine using gas chromatography with ion-pair extraction/on-column alkylation.
abstract: Recent studies have demonstrated the utility of quantitative assays for benzoylecgonine in assessing the efficacy of cocaine-dependence-treatment programs to determine if the amount of cocaine consumed has been reduced. We describe a simple gas chromatographic method for determining benzoylecgonine concentrations in urine. BZE is extracted from urine as an ion pair with tri-n-propylsulfonium ion. Injection into the heated injection port of the gas chromatograph results in thermal conversion of the ion pair to the n-propyl ester of BZE. Using the structural analogue of BZE, m-toluylecgonine, as the internal standard, the analysis is carried out on a (5% phenyl)methylpolysiloxane capillary column with nitrogen-phosphorus detection. There was a good correlation between BZE concentrations determined by gas chromatography-mass spectrometry and concentrations determined by the method described in this paper. Application to cocaine-dependence-treatment programs is discussed.
authors.affiliation: Drug Dependence Research Center, Department of Psychiatry, University of California, San Francisco 94143, USA.
authors.forename: K
authors.initials: K
authors.lastname: Panganiban
authors.forename: P
authors.initials: P
authors.lastname: Jacob
authors.forename: E T
authors.initials: ET
authors.lastname: Everhart
authors.forename: E C
authors.initials: EC
authors.lastname: Tisdale
authors.forename: S L
authors.initials: SL
authors.lastname: Batki
authors.forename: J E
authors.initials: JE
authors.lastname: Mendelson
authors.forename: R T
authors.initials: RT
authors.lastname: Jones
mesh_terms: D000478:Alkylation; D002849:Chromatography, Gas / Q000379:methods*; D003042:Cocaine / Q000031:analogs & derivatives* / Q000737:chemistry / Q000652:urine; D019970:Cocaine-Related Disorders / Q000652:urine; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods; D015813:Substance Abuse Detection / Q000379:methods; D013452:Sulfonium Compounds / Q000737:chemistry*
chemical_list: D013452:Sulfonium Compounds; C005618:benzoylecgonine; D003042:Cocaine