Interferometric electrohydrodynamic tweezers for high-throughput, label-free single-nanoparticle analysis

We introduce Interferometric Electrohydrodynamic Tweezers (IET), a high-throughput platform for single-nanoparticle analysis. IET rapidly traps nanoparticles in under three seconds, overcoming limitations of low throughput and irreversible adsorption. This label-free method enables precise size and shape characterization via interferometric imaging and molecular composition identification through Raman spectroscopy, while particles are in solution. We validate IET by trapping and imaging colloidal beads, and extracellular vesicles (EVs), accurately determining their sizes and chemical composition. As an optofluidics platform, IET advances nanoparticle characterization, offering new possibilities in nanomedicine and environmental monitoring.