NCJ Number
145898
Journal
Journal of Forensic Sciences Volume: 38 Issue: 6 Dated: (November 1993) Pages: 1326-1341
Date Published
1993
Length
16 pages
Annotation
The authors evaluated the newest formulation of the EMIT assay for illicit drugs, EMIT II, and a new immunoassay, OnLine, to screen for marijuana, cocaine, opiates, barbiturates, and phencyclidine.
Abstract
Recently, Syva released a new formulation (EMIT II) of its widely used enzyme immunoassay, and Roche introduced a new assay, OnLine, which uses a unique method based on the agglutination of microparticles. The authors assessed the operating characteristics of both assays, as performed on an Hitachi 717 analyzer, and compared them to each other and to routine RIA procedures for detecting marijuana, cocaine, opiates, phencyclidine, and barbiturates. Over 50,000 routine urine samples were screened with the three immunoassays for these drugs; samples that tested positive by one or more of the tests were submitted for confirmation testing by gas chromatography/mass spectrometry. The number of confirmed positive detected by each immunoassay was calculated. The three immunoassays performed equally well for cocaine and opiates, as each assay detected at least 98 percent of positive Barbiturates showed the greatest disparity, with OnLine detecting 96 percent, EMIT II 85 percent, and RIA 79 percent of confirmed positive samples. Too few phencyclidine positive samples were detected for a method comparison study. The authors recommend the fully automated EMIT II and OnLine assays over current semi- automated RIA tests for large-volume urine testing. The immunoassays perform comparably for some drugs but not for others. 6 tables, 3 figures, and 8 references