Identification of drug glucuronides in human urine by RP-HPLC after derivatization

A method for the identification of four types of drug glucuronides in human urine is presented. The approach involves solid-phase extraction (C18 columns) from acidified human urine and subsequent methylation and acetylation of the extracted drug glucuronides to triacetyl methyl derivatives. These derivatives were identified by RP-HPLC by comparison with synthesized authentic reference compounds. The scope of the method was demonstrated by identification of glucuronides formed by metabolism of clofibrate, phenazone, disulfiram and sulfamethoxazole in urine samples of two male volunteers.