Comparison of matrix solid phase dispersion (MSPD) with a standard solvent extraction method for sulphamethazine in pork muscle using high performance liquid and thin layer chromatography

Abstract
A rapid and simple extraction/clean‐up procedure (matrix solid phase dispersion, MSPD) for the determination of sulphamethazine (SMZ) in pork muscle tissue is compared with a solvent extraction method. Extracts of samples fortified with SMZ or of incurred samples were found to be free from interfering compounds when chromatographed using HPLC or TLC separation systems. Recovery of SMZ from fortified samples is greater than 80% and residue levels of incurred samples found using the MSPD procedure compare favourably with results obtained using the solvent extraction method. Use of aqueous back extraction of SMZ from dichloromethane is also reported as an alternative step to solvent evaporation for ease of use in both the laboratory and in industry (i.e. at slaughter plants).