Lyophilized Exosomes can be used as control standards for multiple applications including FACS, WB, ELISA and as calibration standards for quantitation of exosome-derived markers from endodontium mesenchymal stem cells samples. Compared with fresh exosomes, freeze-drying does not change the stability of exosomes protein and nucleic acid, but it is easy to transport and store for a long time ( 4 °C), and it still maintains the complete morphology and biological function of exosomes after solubilization.