Influence of hydrolysis procedures on the urinary concentrations of codeine and morphine in relation to doping...

A method is described for the GC-NPD determination of urinary codeine and morphine after derivatization with trifluoroacetic anhydride. The lower limit for accurate quantitative determination was 0.05 microgram ml-1. After the oral administration of Bisolvon Griblettes corresponding to 30 mg codeine phosphate to seven subjects maximum codeine concentrations were obtained after 1-2 h and codeine remained detectable generally 24 h post dosing. The mean maximum level was 5.1 +/- 2.8 micrograms ml-1 found after enzymatic hydrolysis with Suc Helix pomatia juice (SHP). Based on these and previous results (mean 6.3 +/- 3.4 micrograms ml-1) a threshold level for codeine of 16 micrograms ml-1 is proposed. Significant differences were noticed between urinary codeine concentrations found after enzymatic hydrolysis with SHP, beta-glucuronidase from Patella vulgata and acid hydrolysis, respectively. Generally, highest values were obtained after SHP, while beta-glucuronidase and especially acid hydrolysis resulted in much lower levels. No morphine could be detected after acid hydrolysis. Concerning doping analysis, in particular the uniformity of methods and interpretation of the results, it is recommended that the hydrolysis method should be specified in the rules of those sporting federations allowing codeine and/or morphine.