Electrical Conductivity of Nanofluids Containing Small Extracellular Vesicles

Small extracellular vesicles (EVs) are negatively charged membrane-bound structures present in biological fluids. They serve as carriers of bioactive molecules and play a crucial role in intercellular communication. With the growing demand to better understand and harness the functionality of small EVs, significant efforts have been dedicated to developing technologies that support fundamental research in this field. In particular, the implementation of innovative approaches for the comprehensive characterization of these vesicles remains a key priority. Despite the well-established fact that small EVs are charged nanoparticles, most characterization studies have centered on their size, surface markers, and molecular cargo, leaving their electrical properties largely unexplored. Gaining a deeper understanding of the electrical behavior of EVs in biological fluids requires simultaneous consideration of both the EVs and the properties of the fluids in which they are suspended. This study investigated the electrical conductivity of EV-based nanofluids, which are solutions composed of small EVs suspended in defined base fluids. Factors considered included EV concentration, EV surface charge, and base fluid ionic strength. The results showed that electrical conductivity of EV-based nanofluids increased proportionally with both the EV content and the ionic strength of the base fluid. These findings contribute to the growing knowledge base on the electrical properties of small EVs and support the development of advanced technologies for their isolation, detection, and characterization. Such advancements enhance research capabilities and facilitate the translation of EV-based approaches into novel clinical applications.