3-hydroxybenzoylecgonine and benzoylnorecgonine

Urinary excretion of ecgonine (EC) was compared to that of cocaine, benzoylecgonine, ecgonine methyl ester and minor metabolites, meta-hydroxybenzoylecgonine, para-hydroxybenzoylecgonine, and norbenzoylecgonine, following controlled administration of oral, intravenous, intranasal, and smoked cocaine. Urine EC concentrations peaked later than all other analytes and had longer detection times than the other minor metabolites. With a 50 ng/mL cutoff concentration and following low doses of 10 to 45 mg cocaine by multiple routes, detection times extended up to 98 h. Maximum concentrations (Cmax) were 6-14 mole % of those for benzoylecgonine, Cmax increased with dose, time to maximum concentration (Tmax) was independent of dose, and route of administration did not have a significant impact on Cmax or Tmax for metabolites. EC is an analyte to consider for identifying cocaine use due to its stability in urine and long detection times.

Topics: Adult; Biomarkers; Cocaine; Gas Chromatography-Mass Spectrometry; Humans; Male; Substance Abuse Detection

A fully automated system utilizing a liquid handler and an online solid-phase extraction (SPE) device coupled with liquid chromatography-tandem mass spectrometry (LC-MS-MS) was designed to process, detect, and quantify benzoylecgonine (BZE), meta-hydroxybenzoylecgonine (m-OH BZE), para-hydroxybenzoylecgonine (p-OH BZE), and norbenzoylecgonine (nor-BZE) metabolites in human urine. The method was linear for BZE, m-OH BZE, and p-OH BZE from 1.2 to 10,000 ng/mL with limits of detection (LOD) and quantification (LOQ) of 1.2 ng/mL. Nor-BZE was linear from 5 to 10,000 ng/mL with an LOD and LOQ of 1.2 and 5 ng/mL, respectively. The intrarun precision measured as the coefficient of variation of 10 replicates of a 100 ng/mL control was less than 2.6%, and the interrun precision for 5 replicates of the same control across 8 batches was less than 4.8% for all analytes. No assay interference was noted from controls containing cocaine, cocaethylene, and ecgonine methyl ester. Excellent data concordance (R2 > 0.994) was found for direct comparison of the automated SPE-LC-MS-MS procedure and an existing gas chromatography-MS procedure using 94 human urine samples previously determined to be positive for BZE. The automated specimen handling and SPE procedure, when compared to the traditional extraction schema, eliminates the human factors of specimen handling, processing, extraction, and derivatization, thereby reducing labor costs and rework resulting from batch handling issues, and may reduce the number of fume hoods required in the laboratory.

Topics: Automation; Chromatography, Liquid; Cocaine; Humans; Solid Phase Extraction; Tandem Mass Spectrometry

Positive benzoylecgonine (BZE) urinalysis results are sometimes challenged in legal and administrative proceedings on the grounds that the presence of BZE is due to the addition of cocaine to the urine sample with subsequent in vitro hydrolysis to BZE. Consequently, counsel for the respondent or defendant may move that an ecgonine methyl ester (EME) analysis be preformed because EME is presumed to be solely an in vivo cocaine metabolite. For these reasons, a sensitive and rapid gas chromatographic-mass spectrometric procedure was developed for the simultaneous analysis of m-hydroxybenzoylecgonine (m-OHBZE), p-hydroxybenzoylecgonine (p-OHBZE), and N-desmethyl benzoyl ecgonine (norBZE), all of which are cocaine metabolites believed to arise exclusively via in vivo metabolism. Analysis of human urine specimens previously reported positive for BZE using GC-MS at the Department of Defense cutoff of 100 ng/mL demonstrated that at least one of the three metabolites was present in 79 of the 82 specimens studied (96.3%). Thus, the simultaneous analysis of r-OHBZE, p-OHBZE, and norBZE could be used to substantiate that the presence of BZE in urine specimens is the result of cocaine ingestion. Additionally, the premise that EME is a "true" in vivo cocaine metabolite was investigated by assessing the stability of cocaine in unpreserved urine samples at several pHs ranging from 5.0 to 9.0.

Topics: Cocaine; Cocaine-Related Disorders; Gas Chromatography-Mass Spectrometry; Humans; Hydrolysis; Substance Abuse Detection