Determination of Migration of Hindered Amine Light Stabilizer UV4050 in Plastic Food Contact Materials by High Performance Liquid Chromatography-Tandem Mass Spectrometry

Migration tests were conducted using water, 4% (volume fraction) acetic acid solution, isooctane, and ethanol solutions with volume fractions of 10%, 20%, 50%, and 95% as food simulants, in accordance with the provisions of GB 5009.156-2016 and GB 31604.1-2015. Direct injection analysis was made on the soaking solution of the 6 food simulants(except isooctane). The 10 mL of isooctane soaking solution was taken, and 10 mL of 40% (volume fraction) methanol solution was added. The mixed solution was shaken for 1 min, and settled for 30 min. The lower methanol solution was collected and passed through a 0.22 μm organic filter membrane. The filtrate was analyzed by the instrument. Chromatographic analysis was performed using ACQUITY UPLC BEH C₁₈ chromatographic column as the stationary phase, and 50% (volume fraction) methanol solution containing 0.1% (volume fraction) formic acid was used as the mobile phase for isocratic elution separation. The mass spectrometry analysis was carried out using the positive ion (ESI⁺) mode of the electric spray ion source and multiple reaction monitoring (MRM) mode. It was shown that linear relationships between values of the mass concentration of hindered amine light stabilizer UV4050 in different food simulants and the peak area were kept in the range of 5-200 μg·L^-1, with lower limits of determination (10S/N) in the range of 0.6-2.4 μg·L^-1. Test for recovery was conducted by the standard addition method, giving recoveries in the range of 88.1%-109%, and RSDs (n=6) of the determined values ranged from 0.90% to 8.9%. The proposed method was successfully used for the analysis of actual plastic food contact material samples.