Extraction of benzoylecgonine from urine specimens with Cerex Polycrom Clin II solid-phase extraction columns and the...

Benzoylecgonine (BZE) extraction from urine was explored using Cerex Polycrom Clin II solid-phase extraction (SPE) columns and the Speedisk 48 Pressure Processor as an alternative to the Prep1 automated sample processor and XTRX Type RP/W columns. Linearity for urine standards extracted using the Cerex-Speedisk method ranged from 20 to 3000 ng/mL. The mean recovery at the 100-ng/mL cutoff for three lots of columns was 92%. The mean of the within-run means for three batches, which had coefficients of variations of 1.8% or less, was 101.3 ng/mL at the 100-ng/mL cutoff level. Forty-six specimens known to contain BZE were analyzed by both the Prep1-Type RP/W and Cerex-Speedisk methods. The correlation for specimen BZE concentrations between the two methods gave an r2 of 0.9999 and a slope of 1.03. The Cerex-Speedisk system is an inexpensive alternative to the Prep1-Type RP/W system. It is less costly, requires little maintenance, has a small footprint, is hood compatible, and can process four times the number of specimens in a given time.