Multi-parameter Characterization of Bacterial Vesicles

Bacterial membrane vesicles (BMVs) are nano-scale lipid vesicles secreted by bacteria during the growth process. BMVs carry nucleic acids and proteins, especially virulence factors and immune regulatory factor for the inter and intra-species communication. BMVs not only affect a variety of biological processes, but have also shown important applications in vaccine and anti-cancer drug development. However, the purification and characterization of BMVs face serious challenges due to sample heterogeneity, small size and sparse contents. Obtaining a high-purity sample of BMVs and analysing this quantitatively poses another urgent challenge for BMVs research.

This study established a quantitative characterization method for the purity, particle concentration and size distribution of BMVs at the single particle level based on the Flow NanoAnalyzer. The separation and purification of BMVs was performed by combining differential centrifugation and density gradient centrifugation.

Figure 1. Purity and particle concentration of BMVs

Figure 2. Size distribution of BMVs.

In this study, a method was established to characterize the purity, particle concentration and size distribution of BMVs based on the Flow NanoAnalyzer. The Flow NanoAnalyzer provides a powerful platform for further research of biological function of BMVs.

CHINESE J ANAL CHEM, 2021, 49(5), 733-742.