Abstract
Over the past few decades, plasma surface modification technique has been widely used to selectively improve surface properties and biocompatibility of materials. In this paper, at first a simple and effective method for the deposition of plasma-polymerized allylamine films onto 316L stainless steel (SS) from an allylamine/nitrogen gas mixture was developed. These amine-rich films were characterized by grazing incidence attenuated total reflection Fourier transform infrared spectroscopy (GATR-FTIR) and X-ray photoelectron spectroscopy (XPS), and the anticorrosion properties were demonstrated by electrochemical analysis. Micro-BCA and quartz crystal microbalance with dissipation (QCM-D) results showed that the higher density of amine groups of the allylamine-nitrogen plasma-polymerized film contributes to more serum protein adsorption which may enhance the adhesion and growth of cells on biomaterials. The in vitro and in vivo anti-inflammatory evaluation was performed and it has been confirmed that these nitrogen-rich surfaces could inhibit the activation of macrophages by down-regulation of the pro-inflammatory cytokines TNF-α and IL-6, and exhibit acceptable tissue-compatibility. It was found that with the help of nitrogen, plasma-polymerized allylamine films presented superior biological properties and provided a high potential application in surface modification of biomedical substrate with desirable clinical performance.