食品接触材料聚氯乙烯中纳米氧化锌迁移特性研究

Migration characteristics of zinc oxide nanoparticles in food contact material polyvinyl chloride

目的研究食品接触材料聚氯乙烯(PVC)中纳米氧化锌(ZnO-Np)迁移特性。方法制备ZnO-Np含量为1%w/w的PVC/ZnO-Np复合材料;利用单颗粒系统串接电感耦合等离子体质谱技术(Sp-ICP/MS)对ZnO-Np迁移过程中的粒径变化进行测定及分析;在20℃、40℃和70℃下对食品模拟物3%乙酸和95%乙醇中的总Zn含量进行ICP/MS测定,以此分析ZnO-Np特定迁移量、迁移率、纳米粒径和迁移形态。结果复合材料中ZnO-Np的初始含量为8.43 g/kg。迁移实验中ZnO-Np在时间点的特定迁移量最小值为(9.27±3.37) mg/kg,最大值(1 947.33±75.02) mg/kg。中位粒径范围为28~1 156 nm。在第15天时的迁移率范围为5.42%~23.01%。结论ZnO-Np在PVC中存在表面迁移和材料溶胀均导致的迁移,迁移过程中有团聚现象发生。PVC/ZnO-Np复合材料盛放酸性、油脂类和高温食品的应用性和安全性应引起持续关注。

Objective To investigate the zinc oxide nanoparticles(ZnO-Np) migration characteristics in the food contact material, namely polyvinyl chloride(PVC). Methods In this study, PVC/ZnO-Np composite with 1% w/w of ZnO-Np was prepared. Single-particle system tandem inductively coupled plasma mass spectrometry(Sp-ICP/MS) was used for the particle size detecting of ZnO-Np during migration. Meanwhile, under the migration conditions of 20 ℃, 40 ℃ and 70 ℃, the total Zn content in food simulants, 3% acetic acid and 95% ethanol, was determined by ICP/MS as a means of analyzing ZnO-Np specific migration, migration rate, nanoparticle size and migration morphology. Results The initial content of ZnO-Np in the composites was 8.43 g/kg. Migration experiments showed a minimum value of(9.27±3.37) mg/kg and a maximum value of(1 947.33±75.02) mg/kg for the specific migration at different time points. The median particle size ranged from 28 nm to 1 156 nm. Migration rates at day 15 ranged from 5.42% to 23.01%. Conclusion The migration of ZnO-Np in PVC is caused by surface migration and material swelling, and aggregation occurs during the migration process. The applicability and safety of PVC/ZnO-Np composites for acidic, fatty, and high-temperature foods should be of ongoing concern.