Rapid detection of opioids in vitreous humor by enzyme immunoassay

Comprehensive and rapid screening of specimens that enter a postmortem forensic toxicology laboratory is essential. Although blood and urine specimens are most commonly utilized for immunoassay screening, this study illustrates the use of vitreous humor for similar purpose. Over a 2-year period, 1233 out of 5471 cases submitted for drug analysis were screened for the presence of opioids in vitreous humor by the Microgenics Cloned Enzyme Donor Immunoassay (CEDIA) DAU opiate assay. Eighty-five of these cases were presumptively opioid positive by the opiate assay. In 75 of the 85 cases (88.2%), at least one opioid | was subsequently confirmed in blood and/or bile. The gas chromatography-nitrogen-phosphorus detection (GC-NPD) screening method employed by this laboratory detected the presence of opioids in 20 of the 75 opioid-confirmed cases (26.6%). Codeine and oxycodone were readily identified by the GC-NPD screen; however, morphine, hydrocodone, hydromorphone, and 6-acetylmorphine were detected primarily by gas chromatography-mass spectrometry. In summary, the CEDIA DAU opiate assay improved the detection of opioids in our casework for the period studied by 1.0% (55/5471).