Bio-inspired barnacle cement nano-composite coating on biodegradable magnesium alloy for cerebrovascular application

Ischemic stroke is on the rise worldwide, and stent intervention is gradually becoming one of the effective treatments. Biodegradable Mg-Zn-Y-Nd alloy (ZE21B) has good mechanical properties and biocompatibility, and has a good application prospect in vascular scaffolds. However, it still suffers from poor corrosion resistance, insufficient endothelialization, and blood-brain barrier (BBB) remodeling. Previously, it was found that constructing a bionic coating of barnacle gum protein cp19k on the surface of ZE21B by electrostatic spraying could improve its corrosion resistance and pro-endothelialization ability. Therefore, we considered piggybacking sulfonated hyaluronic acid nanoparticles (NP@S-HA) on the coating, which inherited the excellent anticoagulant and anti-inflammatory properties of S-HA on the basis of its improved corrosion resistance. The coatings were evaluated by electrochemistry, static immersion corrosion, in vitro blood experiments, and cellular experiments. Collectively, the cp19k/NP@S-HA coating demonstrated an average corrosion resistance enhancement of approximately 40.6% relative to the uncoated ZE21B. Cp19k/NP@S-HA was able to effectively improve the proliferation and migration of endothelial cells, inhibit the proliferation and regulate the contractile phenotype of smooth muscle cells, inhibit macrophage (MA) adherence, regulate the M2 phenotype of MAs, reduce the expression of the inflammatory factor tumor necrosis factor-α (TNF-α), and inhibit fibroplasia. In summary, the composite coatings developed in this study provide an effective strategy for surface modification of magnesium alloys in cerebrovascular applications, which has a broad application prospect.