Impact of the In Vitro Human Digestive Environment on the Interaction Between Vitamin C and Microplastics

Microplastics are present in the environment and living systems and bind with contaminants, proteins, and lipids. However, the interaction of vitamins with microplastics under in vitro conditions is unknown. Therefore, the aim of this study was to evaluate the interaction of vitamin C with microplastics obtained from food packages for simulated intestinal and gastric fluids. Sorption responses (kinetic and isotherm models) were examined using a batch technique with high-performance liquid chromatography-mass spectrometry (HPLC-MS). The results show that the sorption was achieved in 180 and 45 min for gastric and intestinal conditions. Vitamin C was adsorbed between 3 and 20% onto microplastics under in vitro digestive conditions. The sorption of vitamin C on microplastics conformed to the pseudo-second order (PSO) kinetic model. The isotherm models showed that sorption fitted the Temkin and Freundlich models.