Validation of Interferometric Light Microscopy for Assessment of Extracellular Particles in 250 samples of Diluted Plasma: Preparing the Path for Future Clinical Practices

Abstract: In recent years, the analysis of extracellular particles (EPs) has become instrumental in deciphering intercellular communication and disease biomarkers. Interferometric light microscopy (ILM) has emerged as a powerful label-free technique for real-time charac-terization of nanoscale particles. This contribution presents for the first time measure-ments of EPs directly in diluted plasma by ILM on populations of samples. The study involves the measured number density of EPs, the corrected number density of EPs (taking into account dilution of the sample) and the size of EPs. Analysis involves plasma of multiple species—canine, equine, and human. Most of the Dh in all three spe-cies were confined to the interval between 130 nm and 200 nm. We found no statisti-cally significant correlation between the corrected n and Dh indicating good perfor-mance of the method. The correlation between the measured n and Dh was statistically significant indicating hindered movement of EPs due to their higher number density. These results showed that high throughput measurement of number density and size of EPs in plasma is feasible. Keywords: Extracellular vesicles; Interferometric Light Microscopy; Plasma analysis; Nanoparticle characterization; Videodrop technology; Nanoparticles