Physicochemical- and biocompatibility of oxygen and nitrogen plasma treatment using a PLA scaffold

Plasma surface treatment has a wide range of applications in biomedicine. In the present study, flat polylactic acid (PLA) films were treated with oxygen and nitrogen, low-pressure, non-thermal plasma. The water contact angle of the PLA films dramatically decreased from 67° in the untreated surface to 34° and 38° in surfaces treated with nitrogen and oxygen plasma, respectively. Conversely, after the plasma treatment, the surface free energy of the films increased considerably from 45.73 mN/m to 66.51 mN/m. The hydrophilicity potential variations following the plasma treatment were measured by the x-ray photoelectron spectroscopy examination of polar functional groups. Furthermore, surface changes after plasma treatment were examined using atomic force microscopy. The MTT assay showed no changes in cell viability cytotoxicity following the PLA films’ plasma treatment. Moreover, as evidenced by SEM analysis, plasma treatment was found to promote cell growth and adhesion to polymer surfaces. The results were suggestive of modifications due to the PLA’s plasma treatment that may enhance the biological properties of PLA as a scaffold.