Rapid determination of seven synthetic dyes in casual snacks based on packed-fibers solid-phase extraction coupled with HPLC-DAD.

Abstract Based on packed-fiber solid-phase extraction and HPLC-DAD, a simple analytical method for the determination of seven synthetic dyes has been successfully developed. Polystyrene/polypyrrole (PS/PPy) fibers were obtained via electro-spinning of polystyrene skeletal nanofibers, followed by the oxidation with FeCl3 to trigger the polymerization of pyrrole and the deposition of polypyrrole coatings on PS fibrous skeleton fibers. The relationship between the extraction performance of the fibers and the electrospinning process at different humidities was investigated based on morphologic study and BET surface area. In the extraction process, purification, concentration, and desorption could be accomplished in one step. The established method exhibited good sensitivity, selectivity, reproducibility, and good efficiency for synthetic dyes in casual snacks (preserved fruit, flavored yogurt, and fruity hard candy) samples. With optimal conditions, the LODs (S/N = 3) were 2.4 to 21.09 ng mL−1, and linearities were acceptable in liquid matrix and solid matrices. The recoveries were 93.9–103.9%.