Journal of analytical toxicology | 2021
ELISA Screens for Fentanyl in Urine are Susceptible to False-Positives in High Concentration Methamphetamine Samples.
Abstract
Immunoassay techniques are commonly used for urine drug screening in forensic and clinical toxicology laboratories. While these techniques are excellent for the non-specific detection of a wide variety of drug classes, their very nature renders them vulnerable to false negatives and false positives. The New York State Police Forensic Toxicology Laboratory investigated a trend of false positive fentanyl urine drug screens and determined that urine methamphetamine levels in excess of 40 μg/mL can cause a false positive urine fentanyl screening result using the Neogen enzyme-linked immunosorbent assay kit at a 1 ng/mL fentanyl decision point.