Mesenchymal stem cell (MSC) culture supernatant solutions were dried under sub- and supercritical conditions using the precipitation with compressed antisolvent (PCA) process. Of the supernatant components, vascular endothelial growth factor (VEGF) was selected as the target protein. N-Methyl-2-pyrrolidone (NMP) was used as a co-solvent to enhance the miscibility of the supernatant with the antisolvent, CO2. The effects of temperature, pressure, NMP/solution mass fraction, and washing time were observed, and the conditions that allowed more efficient mixing among the solvents yielded the most amount of VEGF with retained activity. The products obtained by the optimum condition in this study were compared to a lyophilized sample. PCA processed samples produced more uniform and less agglomerated particles while exhibiting higher stability when reconstituted in water for 14 days. Although the PCA process was optimized for only VEGF, structures of additional 39 growth factors were also maintained in the dried samples. (C) 2019 Elsevier B.V. All rights reserved.