# A Simple Technique for Studying the Interaction of Polypropylene-Based Microplastics with Adherent Mammalian Cells Using a Holder

## TL;DR

This paper introduces a new method to study how polypropylene microplastics interact with mammalian cells using disposable holders, observing their effects without causing cell death.

## Contribution

A novel experimental setup using disposable holders to enable direct contact between low-density microplastics and adherent cells for interaction studies.

## Key findings

- Microplastics penetrate the cell monolayer and adhere to the cell surface without causing destruction.
- Exposure to microplastics for 24 hours did not induce apoptosis or necrosis in Caco-2 cells.
- The method allows for detailed imaging and analysis of microplastic-cell interactions using confocal and scanning electron microscopy.

## Abstract

Microplastics pose a great challenge to human health and could prove to be the most dangerous environmental contaminant of the 21st century. The study presented here is an attempt at proposing a new methodology for studying the interaction of microplastics with adherent mammalian cells using aides. The disposable holders proposed here provide direct contact between microplastics (with a density lower than that of water) and cells in the course of culturing, which is necessary as we postulate the existence of an interaction. Using several microscopic methods (confocal fluorescence microscopy and scanning electron microscopy (SEM)), we have observed that this interaction causes a non-destructive penetration of the cell monolayer and adhesion of microplastics to the cell surface. The Caco-2 cells were used for the experiments. The said cells are the approximation of the digestive system, which, due to the presence of plastics in drinking water, is particularly vulnerable to direct interactions with these contaminants. Model microplastics were obtained by grinding pellets of chemically pure polypropylene. The imaging of cells in both space and on the surface was supplemented by an assay to determine the cell welfare in the studied microplastic-exposed models, which did not show the occurrence of apoptosis or necrosis after a 24 h exposure.