The quantitative conversion of morphine 3-beta-D glucuronide to morphine using beta-glucuronidase obtained from Patella vulgata as compared to acid hydrolysis.
Methods to confirm morphine in urine require hydrolysis to liberate morphine from its 3-beta-D glucuronide (M-3G) conjugate. Lengthy enzyme hydrolysis procedures prolong testing turnaround time whereas rapid enzyme methods may produce a low conversion of M-3G to morphine. The purpose of this study was to evaluate the quantitative conversion of M-3G to morphine in human urine using a thermally stable beta-glucuronidase isolated from Patella vulgata; to compare these findings with those obtained from acid hydrolysis; and to compare between-run imprecision for both hydrolysis methods. We found both enzyme and acid hydrolysis techniques to be efficient, giving 90.4% and 92.8% conversion of M-3G to morphine, respectively. Also, both methods were found to be reproducible. Over a 14 week period, 20 opiate confirmation batches were analyzed by each hydrolysis method; the coefficient of variation for morphine liberated from M-3G was 5.5% for enzyme hydrolysis and 2.7% for acid hydrolysis.
Department of Pathology, University of Utah School of Medicine, Salt Lake City 84108.
T A
TA
Jennison
E
E
Wozniak
G
G
Nelson
F M
FM
Urry
D000818:Animals; D005966:Glucuronidase / Q000378:metabolism*; D006801:Humans; D006868:Hydrolysis; D008974:Mollusca / Q000201:enzymology; D009020:Morphine / Q000378:metabolism*; D009022:Morphine Derivatives / Q000378:metabolism*
D009022:Morphine Derivatives; D009020:Morphine; D005966:Glucuronidase; C018108:morphine-3-glucuronide