抄録
An ion-pair reversed-phase high-performance liquid chromatographic (HPLC) assay method was developed for the sleep inducer 1- (2-ο-chlorobenzoyl-4-chlorophenyl) -3-dimethylcarbamoyl-5-glycylaminomethyl-1H-1, 2, 4-triazole hydrochloride dihydrate (rilmazafone, 1) in animal feed. This method is an ion-pair reversed-phase HPLC using an octadecylsilane chemically bonded silica gel column and dodecanesulfonic acid as an ion-pairing reagent. It can simultaneously assay drug 1 and its six degradation products. Dodecanesulfonic acid caused retention of three compounds (1, 6 and 7) on the column through the ion-pair effect, with good separation from other neutral and acidic compounds.
The drug was extracted from the feed. After clean-up, the extract was subjected to HPLC, with 1 being assayed with a coefficient of variation of less than 4%. The degradation products can be simultaneously assayed with the same precision even when present at only 2-3 mg/kg. This method was used to confirm the stability of 1 in feed. An HPLC method to assay 1 alone was also established;it is more efficient than our previous fluorometric procedure.
