Evaluation of DRI enzyme immunoassays for drugs-of-abuse screening on the Cobas Mira.
OBJECTIVE
To establish optimal performance parameters (ratios of sample and reagents, reaction time, and distinction of absorbance values between calibrators) on the Roche Cobas Mira analyzer for the evaluation of Diagnostic Reagents Inc enzyme immunoassay reagents for urine screening of amphetamines, cannabinoids, cocaine metabolite, opiates, and phencyclidine.


METHODS
Laboratory in a physician's office.


METHODS
Two laboratorians analyze a daily average of 25 urine samples for employment screening purposes. PRODUCT COMPARISON: DRI reagents were compared to Syva EMIT reagents.


RESULTS
Within-run and between-run precision at the cutoff concentration for DRI reagents ranged from 1.1% to 1.6% CV and 2.2% to 5.7% CV respectively. Results (positive or negative) using DRI or Syva EMIT reagents were identical for cannabinoids, cocaine metabolite, opiates and PCP. Direct comparison for amphetamines was not possible because of different cutoff concentrations of the 2 reagents systems.


CONCLUSIONS
DRI reagents are acceptable alternatives to EMIT reagents for the analysis of amphetamines, cannabinoids, cocaine metabolite, opiates and phencyclidine in urine on the Cobas Mira analyzer. Utilization of DRI reagents for more than 12 months demonstrated the reliability of the reagents and allowed cost comparison.


BACKGROUND
DRI = Diagnostic Reagents Inc; EMIT = enzyme multiplied immunoassay technique; d.a.u. = drugs of abuse; PCP = phencyclidine; GC/MS = gas chromatography/mass spectrometry.
Broussard
L A
LA
Department of Medical Technology, Louisiana State University Medical Center, New Orleans 70112, USA.
Hanson
L
L
D017248:Enzyme Multiplied Immunoassay Technique / Q000295:instrumentation*; D006801:Humans; D015813:Substance Abuse Detection / Q000295:instrumentation*