Considerations for MESF-bead based assignment of absolute fluorescence values of nanoparticles and extracellular vesicles by flow cytometry

Evaluate the advised use of MESF bead-based calibration for the assignment of absolute fluorescent values to nanoparticles and extracellular vesicles.
Conclusion:
Our results indicate that calibration of fluorescent signals is crucial for comparison between platforms, and that it should be utilized and properly reported. Nevertheless, accurate assignment of absolute numbers of MESF/ERF to particles in the sub-micron size, such as nanoparticles and extracellular vesicles, depends on the bead calibrator set used.Furthermore, to avoid inconsistencies we advised that for inter-comparison studies identical calibrator bead sets should be used. QC samples as provided by manufacturers for each instrument (Influx, CytoFLEX and Celesta), in addition to 100 nm polystyrene beads and 200 nm polystyrene beads