Sulfonium salts as derivatizing agents. 3. Quantitation of the cocaine metabolite benzoylecgonine in urine using gas chromatography with ion-pair extraction/on-column alkylation.
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.
Panganiban
K
K
Drug Dependence Research Center, Department of Psychiatry, University of California, San Francisco 94143, USA.
Jacob
P
P
Everhart
E T
ET
Tisdale
E C
EC
Batki
S L
SL
Mendelson
J E
JE
Jones
R T
RT
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*
D013452:Sulfonium Compounds; C005618:benzoylecgonine; D003042:Cocaine