Use of organ-on-chip devices and single particle ICP-MS for assessing dynamic in vitro bioavailability of silver and titanium dioxide nanoparticles from foodstuff.

The most common way to study the cellular transport of nutrients and pollutants when simulating intestinal absorption is to use static in vitro models. However, these approaches are limited by the lack of dynamism in simulating the intestinal absorption process, and they fail to consider the stress created by fluid during this process. The development of micro-physiological systems, such as organ-on-a-chip (OoC), enables the dynamics of the process to be incorporated into the simulation, offering a more realistic approach. This research has studied the potential for using an OoC with Caco-2 cells to simulate the intestinal absorption of inorganic silver and titanium dioxide nanoparticles in food additives (E171) and food, e.g. sugar pearls containing the food additive E174 and seafood, -seaweed and mussels which were exposed to nanoparticles in controlled laboratory trials. A viable cell monolayer was achieved under flow conditions for 96 h using the commercial μ-Slide I Luer 3D microfluidic device. This made possible to carry out cell transport experiments on the bio-accessible fractions obtained from the samples under study. The nanoparticle content (particle number concentration) and particle size distribution were obtained using inductively coupled plasma mass spectrometry working in the single particle mode (spICP-MS). This technique is of great importance to monitor particle size changes given the agglomeration and/or dissolution phenomena that nanoparticles undergo depending on the surrounding environment. To study these processes, complementary techniques such as transmission electron microscopy, were used.