The Study of Collagen Immobilization on a Novel Nanocomposite to Enhance Cell Adhesion and Growth

Background: Surface properties of a biomaterial could be critical in determining biomaterial’s biocompatibility due to the fact that the first interactions between the biological environment and artificial materials are most likely occurred at material’s surface. In this study, the surface properties of a new nanocomposite (NC) polymeric material were modified by combining plasma treatment and collagen immobilization in order to enhance cell adhesion and growth. Methods: NC films were plasma treated in reactive O2 plasma at 60 W for 120 s. Afterward, type I collagen was immobilized on the activated NC by a safe, easy, and effective one-step process. The modified surfaces of NC were characterized by water contact angle measurement, water uptake, scanning electron microscopy (SEM), and Fourier transformed infrared spectroscopy in attenuated total reflection mode (ATR-FTIR). Furthermore, the cellular behaviors of human umbilical vascular endothelial cells (HUVEC) such as attachment, growth and proliferation on the surface of the NC were also evaluated in vitro by optical microscopy and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide test. Results: The outcomes indicated that plasma treatment and collagen immobilization could improve hydrophilicity of NC. SEM micrograph of the grafted film showed a confluent layer of collagen with about 3-5 µm thicknesses. In vitro tests showed that collagen-grafted and plasma-treated surfaces both resulted in higher cell adhesion and growth state compared with untreated ones. Conclusion: Plasma surface modification and collagen immobilization could enhance the attachment and proliferation of HUVEC onto NC, and the method would be usefully applied to enhance its biocompatibility.