MATRIX SOLID-PHASE DISPERSION EXTRACTION AND LIQUID-CHROMATOGRAPHIC DETERMINATION OF NICARBAZIN IN CHICKEN TISSUE

This method outlines the necessary steps for the isolation and determination of the drug nicarbazin in chicken liver and muscle tissue. Tissue samples were blended with octadecylsilyl-derivatized silica packing material (C18). A column made from the C18-tissue matrix is first washed with hexane, and then the 4,4'-dinitrocarbanilide (DNC) portion of the nicarbazin complex is eluted with acetonitrile. After further cleanup using alumina cartridge chromatography, DNC is determined by reversed-phase liquid chromatography with UV detection at 340 nm. Recoveries based on DNC were 95.8 and 83.7% from liver and muscle tissues, respectively. This method and a classical ethyl acetate extraction method gave comparable results on 4 chicken liver and 3 muscle samples that contained incurred nicarbazin residues. C18 sorbents form different manufacturers as well as lipophilic sorbents other than C18 were also studied. The proposed extraction and cleanup procedure requires less than 30 mL solvent, fewer sample manipulations, and does not require solvent partitioning or backwashing of extracts. This combination of characteristics makes this method more attractive than classical isolation procedures for nicarbazin.