Roche Diagnostics Systems, Inc., 1080 US Highway 202, Somerville, NJ 08876, USA

Applications are currently available on the Hitachi 717, 747, 917, Olympus AU800, AU5200, and the Cobas Integra 700. The intra- and inter-assay precision for the entire range of the curve is less than 5% on all instruments tested.

Forty GC/MS positive samples tested positive relative to 300 ng/ml and 2000 ng/ml cutoffs for all applications. Complete agreement with 1000 negative samples ( including 10 GC/MS tested negatives) was shown with OnLine I on all analyzers. Cross-reactivity studies demonstrated similar results when compared to the generation I OnLine Opiate assay.

In addition, this assay was also compared to the new EMIT II opiates assay on the Hitachi 717. Assay precision as CV% was 1.9% at 300 ng/ml (300 ng/ml cutoff) and 3.3 at 2000 ng/ml (2000 ng/ml cutoff) versus 1.1 % at 300 ng/ml and 3.1% at 2000 ng/ml for the EMIT II assay.

Clinical accuracy of these assays at a 300 ng/mL cutoff was tested by using fourteen morphine-positive urines containing no codeine. These samples were diluted to +20% of the cutoff based on GC/MS values. The OnLine II demonstrated a mean recovery of 104% and a mean recovery of 160% with EMIT II. At a 2000 ng/mL cutoff, six undiluted clinical samples containing morphine and/or codeine with GC/MS values ranging from 1228 to 1984 ng/mL were tested. All samples were identified as negative in the OnLine II assay and three of the six were positive in the EMIT II assay. Cross-reactivity studies revealed higher values for hydrocodone and hydromorphone in the EMIT II assay.