Atmospheric pressure plasma surface modification of poly(D, L -lactic acid) increases fibroblast, osteoblast and keratinocyte adhesion and proliferation

An atmospheric pressure plasma deposition for P(d,L)LA (PLA) film was used to modify polymer surface properties using 1,2-diaminopropane and acrylic acid as precursors. These two different plasma coatings result in a high density of amino groups (PLA-NH ₂) and carboxylic groups (PLA-COOH) onto PLA surface as demonstrated by Fourier transform infra-red (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS). Plasma coatings modified PLA surface wettability and proteins adsorption from fetal bovine serum (FBS), influencing cell adhesion and proliferation of 3T3 mouse fibroblast, MC-3T3 E1 mouse pre-osteoblast, and HaCaT cells (human keratinocytes). In particular both coatings increased pre-osteoblast and keratinocyte adhesion while no effect was observed on fibroblast. Moreover, cell proliferation assessed after 48 h by Tox-8 assay was significantly higher for osteoblast cells and keratinocyte seeded onto both PLA-NH ₂ and PLA-COOH compared to cells seeded onto normal PLA. On the basis of the obtained data, the atmospheric pressure plasma deposition described might represent an innovative and useful tool for bone and skin tissue engineering. P(D,L)LA is a widely used biomaterial, with a surface without functional groups (carboxyl, hydroxyl, amino groups) to enhance cell adhesion and growth. To improve its bioactivity, an atmospheric pressure plasma grafting of carboxylic and aminic groups is used, increasing different cell types adhesion and proliferation. This plasma treatment makes P(D,L)LA suitable for tissue engineering applications.