Evaluation of phencyclidine by EMIT d.a.u. utilizing the ETS analyzer and a 25-ng/mL cutoff

This study evaluates the usefulness of the EMIT d.a.u. phencyclidine assay using the Syva ETS instrument to reliably detect phencyclidine in urine specimens at 25 ng/mL and above. More than 1600 urine specimens were screened over a one-month period. Fifty three (53) specimens screened positive (25 of these were previously tested positive by EMIT and GC/MS at or above the 25-ng/ml level and resubmitted as unknowns). Of the 53 specimens, 52 were confirmed positive by GC/MS. Reanalysis by EMIT of the one sample that was confirmed negative by GC/MS yielded a negative result. The absorbance difference between a negative sample and a sample containing 25 ng/mL of phencyclidine averaged 53 absorbance units with a standard deviation of 7.7 units. The absorbance difference between a negative sample and a sample containing 75 ng/mL of phencyclidine averaged 105 absorbance units with a standard deviation of 6.8 units.