Matrix Solid Phase Dispersion Isolation and Liquid Chromatographic Determination of Sulfadimethoxine in Catfish (Ictalurus punctatus) Muscle Tissue
Abstract A method for the isolation and liquid chromatographic determination of sulfadimethoxine In catfish (Ictalurus punctatus) muscle tissue Is presented. Blank control and sulf adlmethox- Ine-fortlfled fish muscle tissue samples (0.5 g) were blended with octadecylsllyl (C18,40 /μm, 18% load, endcapped) derivatlzed silica packing material. A column made from the C18/ fish tissue blend was first washed with hexane (8 mL), following which the sulfadimethoxine was eluted with dlchloromethane (8 mL). The eluant contained sulfadimethoxine analyte that was free from Interfering compounds when analyzed by liquid chromatography with UV detection (photodlode array, 270 nm). Standard curves for sulfadimethoxine Isolated from fortified samples were linear (0.999 ± 0.001) with an average relative percentage recovery of 101.1 ± 4.2% for the concentration range (50, 100, 200,400, 800, and 1600 ng/g) examined using sulfamethoxazole as the Internal standard. The interassay variability was 10.7 ± 8.2% with an Intra-assay variability of 2.2%.