Determination of UV Absorbers and Light Stabilizers in Food Packing Bags by Magnetic Solid Phase Extraction Followed by High Performance Liquid Chromatography

A novel and sensitive solid phase extraction method based on the adsorption of cetyltrimethylammonium bromide (CTAB) on the surface of Fe3O4 nanoparticles was developed for the extraction and preconcentration of trace amounts of UV absorbers and light stabilizers in plastic packaging. The remarkable properties of Fe3O4@CTAB including strong magnetization and high surface area were utilized in the magnetic solid phase extraction procedure, and satisfactory extraction recoveries (84.5-98.9 %) were obtained by using only 12 mg of magnetic adsorbent (200 A mu L, 60 mg mL(-1)). Five parameters on the extraction recovery were investigated, such as the amount of surfactant, pH value, the amount of Fe3O4@CTAB, eluent and sorption time. Under the optimum conditions, the method was linear in the range of 0.5-25 mu g mL(-1) and good linearity (R (2) > 0.996) was obtained for all calibration curves. The limits of detection in the plastic packaging were 0.09 and 0.17 mu g mL(-1) and the relative standard deviations of the analytes (n = 5) were in the range from 0.37 to 2.40 %.