Probe Cytotoxic and Oxidative Stress Effects of Nanoplastics on Caco-2 Cells: Insights from Raman Spectroscopy and Machine Learning.

Nanoplastics and microplastics have become an increasing ecological and health concern due to their widespread presence in the environment and food chain. In this study, Caco-2 cells were used as an in vitro model of the human intestinal epithelium to investigate the cytotoxic effects of polystyrene nanoparticles and microparticles of varying sizes, concentrations, and surface modification. Oxidative stress and apoptosis were evaluated following particle exposure. Raman spectroscopy, combined with machine learning analysis, was employed to detect and characterize biochemical alterations in the cells. Several peak ratios were selected to cluster data depending on size. A correlation between apoptosis and both concentration and Raman score was established highlighting its potential as a non-invasive tool to monitor nanoparticle-induced cellular damage. Resveratrol pretreatment reduced some of these harmful effects of amine-modified nanoplastics, reducing reactive oxygen species generation. This study demonstrates the potential of combining Raman spectroscopy and machine learning to assess the cytotoxic effects of micro- and nanoplastics and identifies protective strategies such as antioxidant pretreatment.