Single-cell extracellular vesicle analysis by microfluidics and beyond

Extracellular vesicles (EVs) are membrane vesicles encapsulated by lipid membranes present in most body fluids. These EVs contain abundant biomolecular composition, including proteins, nucleic acids, lipids, metabolites, etc., and thus play an important role in intercellular communication. However, EVs are highly heterogeneous in terms of physical properties and biomolecular composition. Therefore, it is crucially important to study EV on single cell and single particle level for precise analysis and functional evaluation. Microfluidic platforms provide the possibility for single-cell EV analysis by integrating cell manipulation, EV enrichment, sensitive nucleic acid and protein detection together. In this review, we have summarized current status in single-cell EV and single EV particle study by microfluidic platform with advanced detection tools. The importance of single-cell EV on heterogeneity and future development are also discussed and prospected.