| dc.description.abstract | Implantable medical devices are widely used in clinical medicine. However, they directly contact to blood or body fluid and nonspecific adsorption of protein or microorganisms may occur. This process will lead to decreased efficiency or sensitivity which further facilitates coagulation, infection or thrombus formation. Modification the surface of medical device with antifouling coatings may decrease the possibility of nonspecific adsorption and prevent formation of complications. Among them, modification by self-assembling is an easy and efficient way to improve the biocompatibility. Nevertheless, the stability and effectiveness of self-assembled monolayers (SAMs) is also an issue for long-term biomedical applications.
In this study, we used cysteine (natural sulfur-containing zwitterionic compounds), cysteine betaine (derivative of cycteine with quaternary ammonium group at its terminal end), and polyethylene glycol (a widely used hydrophilic antifouling material) to decorate with Au substrate through Au-thiol interaction. We arranged contact angle goniometer, X-ray photoelectron spectroscopy (XPS), and scanning tunneling microscope (STM) to examine the hydrophilic property, surface elemental composition and molecular arrangement situation in this study. MTT cytotoxicity assays, bacterial adsorption test, 3T3 fibroblast cel�#(~sorption, and protein adsorption were also arranged to compare the range of application and antifouling capacity. Finally, the modification was applied to hollow gold silver nanoshells. After regulating temperature, ion concentration, and protein adsorption, we tested the colloid stability. This technique then applied to near-infrared photoelectron thermal therapy and developed into bio-derived zwitterionic assemblies for antifouling coatings with high potential in clinical implications. | en_US |