title: A novel immunoassay for quantitative drug abuse screening in serum.
abstract: An immunoassay was established which enables a reliable quantification of serological drug samples. The assay is based on a competitive ELISA. In total nine drugs (amphetamine, methamphetamine, 3,4-methylenedioxy-methamphetamine (MDMA), tetrahydrocannabinol (THC), phencyclidine (PCP), methadone, morphine, cocaine and benzoylecgonine) were tested. All reagents had to pass through a stringent validation process. Within the established test for three out of the nine drugs no cross-reactivity with any tested compounds, e.g. serum, other antibodies or chemically related molecules was detectable for the tested antibodies. Furthermore, a sensitive and selective detection was possible, even in the presence of up to 9 drugs or of various anti-drug antibodies. After exclusion of cross-reactivities antibodies against three drugs (methadone, MDMA, benzoylecgonine) were validated, which allowed a specific and sensitive quantification. For the competitive measurements CVs in the range of 2-17% could be reached with LLOQs of 10ng/mL and LODs of 150ng/mL for methadone, 250ng/mL for MDMA and 400ng/mL for benzoylecgonine. Anonymized serum samples (n=10) provided by the office of criminal investigation Berlin were analyzed for verification purposes. Evaluation of these data showed a correlation (CV) of ≈0.9 with standard GC-MS methods. A miniaturization on microarray was possible by using the anti-MDMA antibody for the detection of MDMA in serum. The microarray increased the through-put drastically and enabled the simultaneous quantification of various drugs.
authors.affiliation: Fraunhofer Institute for Cell Therapy and Immunology, Bioanalytics und Bioprocesses, Am Mühlenberg 13, 14476 Potsdam, Germany; Humboldt University Berlin, Department of Biology, Invalidenstr. 110, 10115 Berlin, Germany.
authors.forename: Sarah
authors.initials: S
authors.lastname: Schumacher
authors.affiliation: Fraunhofer Institute for Cell Therapy and Immunology, Bioanalytics und Bioprocesses, Am Mühlenberg 13, 14476 Potsdam, Germany. Electronic address: harald.seitz@izi-bb.fraunhofer.de.
authors.forename: Harald
authors.initials: H
authors.lastname: Seitz
mesh_terms: D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D013287:Illicit Drugs / Q000097:blood* / Q000145:classification; D046228:Microarray Analysis / Q000379:methods*; D012044:Regression Analysis; D015813:Substance Abuse Detection / Q000379:methods*
chemical_list: D013287:Illicit Drugs
keywords: Drug Abuse; Immunoassay; Multiplex; Serum; Validation