An Ultra-Sensitive QCM-Based Detecting Platform for On-Site and Rapid Quantification of Nanoplastics in Bottled Water

The release of nanoplastics (NPs) from plastic bottled water containers has emerged as a concealed yet critical threat to water quality and consumer health. Yet, on-site and rapid quantification of NPs, particularly at environmentally relevant trace levels, remains a formidable analytical challenge. Here, we reported an ultrasensitive detection platform that integrates a quartz crystal microbalance (QCM) with a custom-engineered nanoporous sensing chip, enabling real-time, field-deployable quantification of NPs in bottled water with a detection limit of 0.39 μg·L-1. The platform achieves quantitative analysis of multiple NP types, including poly(methyl methacrylate) (PMMA), polyethylene terephthalate (PET), poly(vinyl alcohol) (PVA), polyvinyl chloride (PVC), polystyrene (PS), and carboxylated PS (PS-COOH), with a surface mass sensitivity of 17.7 ng·cm-2·Hz-1. Comprehensive interfacial characterization, supported by molecular simulations, shows that electrostatic attraction facilitates initial NP capture, whereas van der Waals interactions stabilize the adsorbed state, with PET exhibiting particularly favorable adsorption energetics. Leveraging this mechanism, we then conceived a portable device and validated its performance across diverse real-world scenarios involving PET-contaminated bottled water. The system demonstrated robust reliability and analytical fidelity under field conditions. This work establishes a QCM-based analytical paradigm for NP quantification and delivers a deployable technological solution for on-site, rapid, and trustworthy monitoring of NPs in drinking water matrices.