Extracellular vesicles (EVs) are secreted by all living cells and are found in many body fluids. They exert numerous physiological and pathological functions and serve as cargo shuttles. Due to their safety and inherent bioactivity, they have emerged as versatile therapeutic agents, biomarkers, and potential drug carriers. Despite the growing interest in EVs, current progress in this field is, in part, limited by relatively inefficient isolation techniques. Conventional methods are indeed slow, laborious, require specialized laboratory equipment, and may result in low yield and purity. Researchers from ETH Zurich have developed an electrochemically controlled “all-in-one” device enabling capturing, loading, and release of EVs. The device is composed of a fluidic channel confined within antibody-coated microstructured electrodes. It rapidly isolates EVs with a high level of purity from various biofluids such as urine and serum. As a proof of principle, the device was applied to isolate EVs from skin wounds of healthy and diabetic mice. Strikingly, it was found that EVs from healing wounds of diabetic mice were enriched in mitochondrial proteins compared to those of healthy mice. Additionally, the device improved the loading protocol of EVs with polyplexes, and might therefore find applications in nucleic acid delivery. Overall, the electrochemical device could greatly facilitate the development of EV-based technologies.
Schematic representation of the electrochemical device and operation process
A) Device setup, B)electrode previously modified with amino groups, C) antibody conjugation, D) biofluid injection, E) controlled release of the attached EVs by applying voltage, F) optional step- injection of transfection medium in order to form EV-nucleic acid: transfection complexes followed by a washing step, G) release of the loaded EVs by applying voltage. H) Release mechanism of the EVs from the electrodes’ surface.