Evolution of cross-linked polyethyleneimine/SABO®STAB as an efficient sorbent for extraction of pesticides in fruit and vegetable juices

The novel cross-linked polyethyleneimine/SABO®STAB was synthesized and used as an efficient sorbent for dispersive micro-solid phase extraction of pesticides before gas chromatography–micro-electron capture detection. The sorbent was fully characterized using Fourier transform infrared spectroscopy, scanning electron microscopy, thermogravimetric analysis, differential scanning calorimetry, Brunauer–Emmett–Teller, and Barrett–Joyner–Halenda techniques which confirmed thermally stable cross-linked polymer composite with large surface area and mesoporous morphology. The significant parameters, including type and volume of desorption solvent, extraction time, sorbent dosage, and pH of the sample solution, were optimized. The analytical characteristics of the method were validated using a matrix-matched calibration method. The linear dynamic range was 0.85–250 µg L −1 with good determination coefficients ( R 2 > 0.996). The limits of detection were 0.25–0.44 µg L −1 . Finally, the method was applied for the determination of chlorpyrifos and hexaconazole in celery and apple juices, and the relative recoveries were in the range of 75–116% with the RSDs of 2.7–3.6%.