title: Assessment of an automated immunoassay based on kinetic interaction of microparticles in solution for determination of opiates and cocaine metabolite in urine.
abstract: A recently introduced automated immunoassay which is based on kinetic interaction of microparticles in solution (Roche ONLINE), was evaluated for the detection of cocaine metabolite benzoylecgonine (BE) and opiates in human urine. Cross-reactivity for the opiates morphine (100%), codeine (88%), 6-monoacetylmorphine (88%), and morphine 3-glucuronide (72%) was assessed. Analytical recovery evaluated on blank urines spiked with 0, 250, 300, 350, and 500 micrograms/L of morphine and BE (n = 10), varied from 85.2 to 100.2% for opiates and from 81.4 to 93.1% for the cocaine metabolite. The within-day precision ranged from 1.4 to 4.7% for morphine and from 4.2 to 4.8% for BE. The repeatability of the standards over 1 month was 1.0-3.3% for opiates and 1.7-5.1% for BE, and thus allowing measurements to continue over 30 days without re-calibration. This method compared favourably with the SYVA EMIT d.a.u system and gas chromatography/mass spectroscopy (GC/MS) methods.
authors.affiliation: Graduate Program in Forensic Science, University of Alabama at Birmingham, USA.
authors.forename: F P
authors.initials: FP
authors.lastname: Smith
authors.forename: C
authors.initials: C
authors.lastname: Lora-Tamayo
authors.forename: R
authors.initials: R
authors.lastname: Carvajal
authors.forename: B
authors.initials: B
authors.lastname: Caddy
authors.forename: F
authors.initials: F
authors.lastname: Tagliaro
mesh_terms: D001322:Autoanalysis; D002845:Chromatography / Q000379:methods; D003042:Cocaine / Q000031:analogs & derivatives / Q000378:metabolism* / Q000652:urine*; D003061:Codeine / Q000276:immunology / Q000652:urine; D003429:Cross Reactions; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D013058:Mass Spectrometry / Q000379:methods; D009020:Morphine / Q000276:immunology / Q000652:urine; D009022:Morphine Derivatives / Q000276:immunology / Q000652:urine; D009294:Narcotics / Q000652:urine*; D011933:Reagent Kits, Diagnostic; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D009022:Morphine Derivatives; D009294:Narcotics; D011933:Reagent Kits, Diagnostic; C005618:benzoylecgonine; D009020:Morphine; D003042:Cocaine; C026979:6-O-monoacetylmorphine; D003061:Codeine