Evaluation of KIMS immunoassays on a cobas c 501 analyzer for drugs of abuse and ethyl glucuronide testing in urine for forensic abstinence control. Issue 8 (24th February 2017)

• Record Type: Journal Article
• Authors: Neukamm, Merja A.; Bahrami, Arsham; Auwärter, Volker; Mehne, Felix M.P.; Höss, Eva
• Is Part Of: Drug testing and analysis. Volume 9:Issue 8(2017)
• Page Start: 1217
• Page End: 1223
• Publication Date: 2017-02-24
• Subjects: urine screening -- cut‐off -- sensitivity -- cross reactivity -- medico‐psychological assessment; Drugs -- Analysis -- Periodicals; Drug testing -- Periodicals; Chemistry, Forensic -- Periodicals; 615.1901
• DOI: 10.1002/dta.2154
• Languages: English
• ISSNs: 1942-7603

Abstract

Abstract : For the medico‐psychological assessment (MPA) during driving licence re‐granting in Germany, abstinence control including urine samples is required. In these programmes, even small amounts of markers for drug or alcohol abuse have to be detected. Thus, the concentrations of the target compounds are very low, and, in consequence, the sensitivity of the applied screening method has to be much higher than for clinical use. Modified drugs of abuse and ethyl glucuronide immunoassays on a Roche cobas c 501 analyzer were evaluated for precision, accuracy, onboard calibration stability, cross reactivity, sensitivity, and specificity using authentic urine samples. Precision (intra‐day and inter‐day relative standard deviation (RSD) and accuracy (bias) at three concentrations were 12% or lower for all parameters. The calibrations remained stable (deviations <25%) for at least 28 days for all assays except amphetamines (21 days). Satisfactory cross reactivity was determined for the relevant analytes and also for several new psychoactive substances (NPS). The sensitivity was 100% for all parameters except methadone metabolite EDDP (92%) and fully met the sensitivity criteria for MPA urine testing. The presented kinetic interaction of microparticles in a solution (KIMS) immunoassays on a cobas c 501 thus provide a new method to reliably detect drug or alcohol consumption in abstinence control programmes requiring high sensitivity. Copyright © 2016 John Wiley & Sons, Ltd. Abstract : Drugs of abuse immunoassays (KIMS, DRI) for urine screening were evaluated on a cobas c 501 using authentic urine samples and quality controls. Relative standard deviation and bias were below 12%, onboard calibration stability was in the range of 21 to 28 days, cross reactivity was determined for a number of new psychoactive substances, sensitivity was 100% for all analytes except EDDP, and specificity was below 90% for amphetamines and benzodiazepines only. The immunoassays fulfil the requirements for forensic abstinence control.