▎ 摘　　要

Corrosion control of bioabsorbable Mg alloy stents is an attractive topic in recent years. Biodegradable polymer modification is a potential anti-corrosion method, but cannot achieve the desired corrosion protection due to the high water permeability of biodegradable polymers. In this study, a strengthened corrosion control strategy is proposed: Graphene oxide (GO) was introduced into a poly(trimethylene carbonate) (PTMC) coating to improve its anti-corrosion performance. GO/PTMC composite coatings with different GO contents were applied to AZ31b Mg alloy surfaces, and the effect of GO content (0, 0.2, 1, 3, 6, and 10 wt%) on surface characteristics, corrosion resistance, and in vitro biosafety was investigated. The results showed that the increase of GO content in the PTMC coating (<6 wt%) could improve its corrosion resistance by prolonging the permeation path of solution. Meanwhile, the addition of GO (<6 wt%) had little negative effects on cytocompatibility and hemocompatibility. However, when the addition of GO exceeded 6 wt%, GO aggregated on the coating surface, resulting in the formation of new defects and a rapid decrease in corrosion resistance. The optimized sample (GO content: 6 wt%) had the highest impedance modulus of 8.9 x 10(7) Omega.cm(2) at 0.1 Hz and good in vitro biocompatibility, which shows great potential for application in vascular stents.