Dynamic Stomach
Model–Capillary Electrophoresis–ICPMS
for Evaluation of Release and Transformation Behaviors of Arsenic
Species from Microplastics during Digestion
posted on 2024-04-23, 17:12authored byXiao Zhang, Xin-Yi Jiang, Ji-Ying Cai, Shuai Chen, Yong-Liang Yu, Jian-Hua Wang
Microplastics (MPs) can act as carriers of environmental
arsenic
species into the stomach with food and release arsenic species during
digestion, which threatens human health. Herein, an integrated dynamic
stomach model (DSM)-capillary electrophoresis-inductively coupled
plasma mass spectrometry (CE-ICPMS) is developed for online monitoring
of the release and transformation behaviors of arsenic species loaded
on MPs (As-MPs) in the simulated human stomach. The 3D-printed DSM
with a soft stomach chamber enables the behaviors of gastric peristalsis,
gastric and salivary fluid addition, pH adjustment, and gastric emptying
(GE) to be controlled by a self-written program after oral ingestion
of food with As-MPs. The gastric extract during digestion is introduced
into the spiral channel to remove the large particulate impurity and
online filtered to obtain the clarified arsenic-containing solution
for subsequent speciation analysis of arsenic by CE-ICPMS. The digestion
conditions and pretreatment processes of DSM are tracked and validated,
and the release rates of As-MPs digested by DSM are compared with
those digested by the static stomach model and DSM without GE. The
release rate of inorganic arsenic on MPs is higher than that of organic
arsenic throughout the gastric digestion process, and 8% of As(V)
is reduced to As(III). The detection limits for As(III), DMA, MMA,
and As(V) are 0.5–0.9 μg L–1 using
DSM-CE-ICPMS, along with precisions of ≤8%. This present method
provides an integrated and convenient tool for evaluating the release
and transformation of As-MPs during human gastric digestion and provides
a reference for exploring the interactions between MPs and metals/metalloids
in the human body.