A Microfluidic Platform for Enhanced Labelling and Detection of Extracellular Vesicles

It is essential to develop precise labelling techniques of extracellular vesicles (EVs) with minimum disturbance on their detection and characterization. Current methods including using fluorescent probes to conjugate phospholipids or membrane proteins have certain limitations due to EV steric hindrance, dye aggregation, etc. In this study, we propose a microfluidic platform that can significantly enhance EVs’ labelling efficiency while effectively retaining low background noise and high sample throughput. Flow cytometry analysis (FCM) results show that EV labelling by utilizing this platform possesses the merits of a higher labelling efficiency compared to the conventional co-incubation method, by using extremely low dye concentrations to avoid false positive signals. The labelled EVs exhibit good biological activity verified by cell migration assays. These findings highlight the potential of our method for efficient EV labelling, which is essential for accurate EV quantification and analysis.