Protein adsorption and cell adhesion behavior of engineering plastics plasticized by supercritical carbon dioxide

We aimed to evaluate the biological properties of engineering plastics (PC, PSU, PAR) processed using supercritical carbon dioxide (scCO₂). Conventional mold process was used to prepare disk-shaped samples that were then plasticized by scCO₂ at temperatures lower than the glass transition temperature (T_g) of the polymers. Surface roughness, contact angle, and amount of adsorbed protein on the surface were increased after treatment. The surface roughness of PC was significantly changed by scCO₂ treatment. Cell adhesion and proliferation changed according to the differences in surface roughness. Initially, the cell adhesion decreased in all scCO₂-treated polymers. At 3 day, the cell proliferation on scCO₂-treated PC was lower than that on non-treated PC, while that on treated and non-treated PSU and PAR samples remained unaltered. These results suggest that when supercritical treatment is performed under conditions that affect the surface properties of the material, we should consider that cell adhesion and proliferation may change.