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Detection and Identification of Leachables in Vaccine from Plastic Packaging Materials Using UPLC-QTOF MS with Self-Built Polymer Additives Library.

The direct contact of plastic parts with the medical products raises the possibility that plastic-related contaminants (leachables) may be present in the finished medical product. The leachable components from plastic materials may impact the safety and efficacy of the final medical product, so identification and determination of the leachables are essential for the safety assessment of medical products. A method to identify main leachables-polymer additives in medical products was developed by ultraperformance liquid chromatography-quadrupole time-of-flight-mass spectrometry (UPLC-QTOF MS) and a self-built library. The library contains 174 additives and the information on their names, formulas, structures, retention times, fragments, classifications, origin, and corresponding MS(E) and MSMS spectra. The reliability of the construction process of the library was guaranteed by the system stability and suitability test. Identification parameters of library application, such as mass error, retention times, fragments, and isotope pattern, were evaluated. Leachables in real vaccine and the intermediates were identified using automatic library searching. In vaccine, the peak m/z 239.0887 that could not be assigned by the library was identified as dimethyl 2-hydroxy-1,3-cyclohexanedicarboxylate using a series of elucidation tools. As a result, the concentrations of leachables in vaccine and the intermediates ranged from 0.85 to 21.91 μg/L.