LC-MS/MS Determination of Migration of 18 Photoinitiators in Food Contact Paper Based Materials with Printing UV-Ink

4% (φ, the same below) acetic acid solution, 50% (φ, the same below) alcohol solution, 95% alcohol solution and olive oil were used as food simulants to simulate migration behavior of food contact materials in contact with different types of food. LC-MS/MS was applied to the determination of migration of 18 photoinitiators in food contact paper based materials with printing UV-ink. The aqueous food simulant solution was just filtered through filter before injection, and the oil food simulant solution was extracted by acetonitrile before determination. The solution was separated on C₁₈ chromatographic column using a gradient elution program with the mixture of 0.1% (φ) formic acid solution and 0.1% (φ) formic acid in acetonitrile solution mixed in different ratios as mobile phase. The quantitative and qualitative ions of 18 photoinitiators were monitored by MS with multiple reactions monitoring. Linear relationships between values of peak area and mass concentration or mass fraction of 18 photoinitiators were kept in the same range of 3.0-37.5 μg·L^-1 or 0.010-0.125 mg·kg^-1, with lower limits of determination (10S/N) of 0.03-2.97 μg·L^-1 for 4% acetic acid solution, 0.02-2.91 μg·L^-1 for 50% alcohol solution, 0.03-2.88 μg·L^-1 for 95% alcohol solution and 0.06-9.00 ng·g^-1 for olive oil, respectively. On the base of blank sample, test for recovery was made by standard addition method; values of recovery found were in the range of 86.0%-114%, with RSDs (n=6) of determined values no more than 9.4%.