Single Nanoplastics Detection and Nano-Chemical Analysis of Surface Degradation in Commercial Bottled Water

<title>Abstract</title> Nanoplastics (NPs) are emerging as widespread environmental and food contaminants, posing significant concerns because of their potential to penetrate biological membranes, accumulate in tissues, and induce toxic effects. For understanding the impact of NPs on human health, a detailed characterization of their complex physicochemical properties is required. Yet, current analytical methods either lack single-particle spatial resolution, sensitivity, or specificity to detect and analyse NPs contaminating real samples. Here, for the first time, we detect and perform a nano-analytical characterisation of single NPs isolated from commercial drinking water as small as 30 nm; combining spatially confined hyper-concentration, fluorescence-guided nano-imaging, and chemical analysis via infrared nanospectroscopy. Our novel approach offers high-throughput single-particle analysis in real samples, enabling a multimodal characterisation of their 3D morphology, size, chemical identity, and surface degradation. This work paves the way to detect and analyse NPs in complex food matrices and biological systems, to study their interactions, fate, and toxicity.