L. Bujan et al., Comparison of two chromatographic methods for the determination of cocaineand its metabolites in blood and urine, ANAL LETTER, 34(13), 2001, pp. 2263-2275
After a solid-phase extraction, two chromatographic procedures (GC/FID and
HPLC/UV detector) for the determination of cocaine and its metabolites (ben
zoylecgonine and ecgonine methyl ester) in human blood and urine have been
developed. Linear calibration curves were obtained in urine over the concen
tration ranges of 0.16-4 mug/mL and 0.2-4 mug/mL, by GC and HPLC, respectiv
ely; and, in blood, between 0.1 and 2 mug/mL, by both methods. The recoveri
es ranged from 66% to 83% for GC, and from 61% to 95% for HPLC. The limit o
f detection was found to be below 76ng/mL for all the analytes. Precision a
nd accuracy were studied with acceptable results. The methods have been app
lied simultaneously to quantitate the compounds in real samples; concentrat
ions of cocaine and benzoylecgonine determined by GC/FID correlated well wi
th those determined by HPLC/UV in most cases.