Quantitation of benzoylnorecgonine and other cocaine metabolites in meconium by high-performance liquid chromatography.

A method for simultaneous extraction of cocaine and metabolites benzoylnorecgonine, benzoylecgonine and norcocaine from meconium was developed. The procedure uses solid-phase extraction columns with both cation-exchange and hydrophobic properties after vortex-mixing meconium with methanol. Chromatography utilizes reversed-phase high-performance liquid chromatography with a C18 column and phosphate buffer-acetonitrile as mobile phase. The method is specific and sensitive to 50 ng/g meconium for all compounds. Standard curves are linear from 0.05 to 5.0 micrograms/g (r2 > or = 0.989). Intra-assay coefficients of variation were < or = 6.9%. Meconium from infants exposed to cocaine in utero contained varying combinations of the four drugs.