Evaluation of sample treatment procedures for the routine identification and determination at nanogram level of O6‐monoacetylmorphine in urine by capillary GC and dual NPD‐FID

Three methods were evaluated for the determination of O6‐monoacetylmorphine (6‐MAM), the specific metabolite of heroin in human urine, by GC‐NPD‐FID. The procedure devised for a hydrophobic cation exchange column showed superior performances over the liquid‐liquid extraction technique and solid phase extraction with C18. 6‐MAM can be analyzed in random urines at the 2 ng/mL concentration with classical equipment for the differentiation between heroin intake and opiates from various origins. The procedure was also applied to enzymatic and acid hydrolyzates of urines. The simultaneous presence of morphine and codeine are useful in the interpretation of results.