title: Direct and efficient liquid chromatographic-tandem mass spectrometric method for opiates in urine drug testing - importance of 6-acetylmorphine and reduction of analytes.
abstract: Opiates comprise a class of abused drugs that is of primary interest in clinical and forensic urine drug testing. Determination of heroin, codeine, or a multi-drug ingestion is complicated since both heroin and codeine can lead to urinary excretion of free and conjugated morphine. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) offers advantage over gas chromatography-mass spectrometry by simplifying sample preparation but increases the number of analytes. A method based on direct injection of five-fold diluted urine for confirmation of morphine, morphine-3-glucuronide, morphine-6-glucuronide, codeine, codeine-6-glucuronide and 6-acetylmorphine was validated using LC-MS/MS in positive electrospray mode monitoring two transitions using selected reaction monitoring. The method was applied for the analysis of 3155 unknown urine samples which were positive for opiates in immunochemical screening. A linear response was observed for all compounds in the calibration curves covering more than three orders of magnitude. Cut off was set to 2 ng/ml for 6-acetylmorphine and 150 ng/ml for the other analytes. 6-Acetylmorphine was found to be effective (sensitivity 82%) in detecting samples as heroin intake. Morphine-3-glucuronide and codeine-6-glucuronide was the predominant components of total morphine and codeine, 84% and 93%, respectively. The authors have validated a robust LC-MS/MS method for rapid qualitative and quantitative analysis of opiates in urine. 6-Acetylmorphine has been demonstrated as a sensitive and important parameter for a heroin intake. A possible interpretation strategy to conclude the source of detected analytes was proposed. The method might be further developed by reducing the number of analytes to morphine-3-glucuronide, codeine-6-glucuronide and 6-acetylmorphine without compromising test performance.
authors.affiliation: Division of Clinical Pharmacology, Karolinska Institute and University Hospital, Stockholm, Sweden.
authors.forename: Maria
authors.initials: M
authors.lastname: Andersson
authors.forename: Nikolai
authors.initials: N
authors.lastname: Stephanson
authors.forename: Inger
authors.initials: I
authors.lastname: Ohman
authors.forename: Tommy
authors.initials: T
authors.lastname: Terzuoli
authors.forename: Jonatan D
authors.initials: JD
authors.lastname: Lindh
authors.forename: Olof
authors.initials: O
authors.lastname: Beck
mesh_terms: D000701:Analgesics, Opioid / Q000378:metabolism / Q000652:urine*; D002853:Chromatography, Liquid / Q000379:methods; D006801:Humans; D057230:Limit of Detection; D009022:Morphine Derivatives / Q000378:metabolism / Q000652:urine*; D015813:Substance Abuse Detection / Q000379:methods*; D053719:Tandem Mass Spectrometry / Q000379:methods*; D016482:Urinalysis / Q000379:methods
chemical_list: D000701:Analgesics, Opioid; D009022:Morphine Derivatives; C026979:6-O-monoacetylmorphine
keywords: 6-acetylmorphine; LC-MS/MS; interpretation; opiates; urine