LAUSR

This manuscript presents an effective and robust method for simultaneous stereoselective determination of two pyrethroid insecticides-tetramethrin and α-cypermethrin in different food products by HPLC. Enantioseparation was carried out using reversed-phase chromatography and the influences of four polysaccharide-based chiral column, mobile phase composition and column temperature on retention were fully investigated. Satisfactory separation was obtained on Chiralpak IG column using acetonitrile-water (75:25, v/v) under isocratic conditions. In order to extract and purify the target analytes from food matrices, matrix solid phase dispersion (MSPD) was employed with C18 as dispersant and primary secondary amine (PSA) as well as graphitized carbon black (GCB) as clean-up sorbent. Response surface method based on Box-Behnken design (BBD) was implemented to assist optimization of the extraction variables. Then, method validation was done in real samples including specificity, linearity, sensitivity, trueness, precision as well as stability and its analytical performance fulfills the criteria recommended by the European Union SANTE/11945/2015, demonstrating its applicability in studying the stereochemistry of chiral tetramethrin and α-cypermethrin in food products.