Preparation of Graphene Mediated Macrophage Membrane Coating and Its Effects on the Anti-fouling and Immunomodulatory Properties of Tianium Implants

Titanium implants are susceptible to biofouling and inflammatory reactions, which can lead to poor bone fusion and implant failure. In this paper, we fixed graphene to the surface of titanium implant by polydopamine and then bound the M-2 macrophage membrane to the graphene surface via the extremely strong interaction force between graphene and phospholipid in the cell membrane to create a bioactive cell membrane coating at the macroscopic level. This homogeneous cell membrane coating has excellent resistance to biological contamination, which can effectively prevent non-specific adsorption of proteins. Titanium implants with cell membrane coatings showed excellent biocompatibility due to the high cellular affinity of native cell membranes. In addition, immunofluorescence and RT-qPCR (Real-time quantitative polymerase chain reaction) were used for detection of proinflammatory markers(iNOS, TNF-alpha) and anti-inflammatory markers(IL-10, IL-1ra). In an inflammatory environment, the experimental results showed that the modified cell membrane-coated titanium implants could induce the polarization of macrophages to M-2 type and had excellent immunomodulatory ability. This cell membrane coating preparation strategy, relying on the interaction force between graphene and phospholipids, provides ideas for solving the problems of bio-contamination and inflammatory response of titanium implants.