Real-time monitoring of bacterial extracellular vesicles using nanopore technology

Researchers at the University of Notre Dame have developed a novel method to study individual extracellular vesicles (EVs) in real time without the need for extensive sample preparation. EVs are tiny membrane-bound particles released by cells, including bacteria, that play crucial roles in communication, infection, and immune responses. However, because EVs vary widely in size and content, analyzing them individually is essential to understanding their biological functions.

To address this challenge, the research team utilized nanopore-based zero-mode waveguides (ZMWs)—tiny nanostructures that can trap single EVs while excluding larger bacterial cells. This method allows scientists to study hundreds of EVs at once in a highly controlled environment, offering insights into their behavior and diversity. Using fluorescent markers to label the EV membranes, the researchers were able to track how individual vesicles interact and respond to changes in their environment.

One major advantage of this technique is that it eliminates the need for time-consuming steps like EV isolation and concentration, making it possible to analyze bacterial EVs directly in their culture medium. By creating large 21 × 21 arrays of ZMWs, the system enables parallel monitoring of 441 individual EVs simultaneously, providing a much clearer picture of EV population dynamics than traditional bulk analysis methods.

This breakthrough allows researchers to observe how bacterial EVs change in response to environmental factors in real time, offering valuable insights for fields like infectious disease research and vaccine development. By improving our ability to study EV heterogeneity, this approach could pave the way for better diagnostics and treatments targeting bacterial infections.