Evaluation of different food matrices via a dihydropteroate synthase-based biosensor for the screening of sulfonamide residues

In a previous study, we developed a dihydropteroate synthase (DHPS)-based biosensor for multi-sulfonamides (SAs), which could detect 29 SAs with IC50 values below 100 ng mL(-1). The purpose of the present study was to apply the DHPS-based biosensor to different food matrices and evaluate the influence of matrix effects on the performance of the biosensor by using sulfamethazine (SMZ) as a reference analyte. The results show that different sample pretreatment procedures were required for each food sample to ensure the accuracy and precision of the biosensor. The limit of detection (LOD) for SMZ in chicken, pork, egg and honey was 17.82, 20.55, 23.22, and 5.57 mu g kg(-1), respectively. The recovery values ranged from 47.6% to 135.1%, and the coefficients of variation (CV) were less than 25.6%. Taken together, our findings show that the DHPS-DHPPP biosensor is a suitable screening method for the screening of multi-SAs in different food matrices.