Development and evaluation of immunochromatographic rapid tests for screening of cannabinoids, cocaine, and opiates in urine.

The test principle and the optimization of the reactive ingredients are described for the one-step dip and-read immunochromatographic FRONTLINE rapid tests for drugs-of-abuse testing in urine samples. In a multicenter evaluation the rapid tests were compared with FPIA and EMIT immunoassays. Discrepant results were further analyzed by gas chromatography-mass spectrometry methods. In the comparison of the cannabinoids rapid tests versus both immunoassays using clinical and forensic urine samples (399 versus FPIA and 755 versus EMIT), sensitivities and specificities were 97% or better for both comparisons. For cocaine, a sensitivity of 100% versus both routine technologies was obtained, whereas the specificity was reduced somewhat to 91% because of some cross-reactivity with metabolites of methadone and of clozapine. Specificity was very high for the cocaine rapid tests (98-100%) when applied to urine samples of persons not in a methadone maintenance program. Sensitivities and specificities for the opiates rapid tests were 99% or better at all sites when compared with the routine methods. In the screening of about 1200 clinical urine samples for cannabinoids, cocaine or opiates misuse only six samples would have stayed undetected by rapid test analyzes. These results show the FRONTLINE assays allow a reliable and immediate screening for drugs of abuse.