Rapid determination of 48 contaminant residues in food contact plastic products by ultra performance liquid chromatography-quadrupole/electrostatic field orbitrap high resolution mass spectrometry coupled with microwave-assisted extraction

An ultra performance liquid chromatography-quadrupole/electrostatic field orbitrap high resolution mass spectrometry (UPLC-Q Orbitrap HRMS) method was developed for the rapid determination of 48 contaminant residues in food plastic packaging materials. The samples were extracted with methanol using microwave-assisted extraction. The separation of the 48 contaminants was performed on a CAPCELL PAK MG Ⅱ C18 column (150 mm×2.0 mm, 5 μm) with gradient elution. Methanol (containing 0.04% (v/v) formic acid) and water (containing 0.04% (v/v) formic acid and 20 mmol/L ammonium acetate) were used as mobile phases. The compounds were detected under the full scan/date dependent-MS/MS (Full MS/dd-MS2) mode with a heated electrospray ionization (HESI) source. The calibration curves were linear with correlation coefficients no less than 0.9950. The limits of detection (LODs) ranged from 0.1 to 1.0 μg/kg. The average spiked recoveries of the 48 target compounds were between 71.2% and 108.8%, with relative standard derivations (RSDs) ranging from 2.2% to 11.8% (n=6). Compared to previous methods, this method has advantages of simpler sample preparation and higher sensitivity.