Study On Corrosion Resistance And Biocompatibility Of HA-ASTA Coating On ZE21B Alloy

Cardiovascular diseases have become a major threat to global public health,and stent intervention is currently one of the effective methods to treat cardiovascular diseases.As a new type of biodegradable metal,magnesium alloy has great potential applications in cardiovascular stents,the degradable magnesium alloy stents currently used clinically are still limited by the excessive degradation rate and the delayed surface endothelialization.In order to solve the problem of delayed endothelialization of magnesium alloy surface,HA-ASTA coating was prepared on the surface of ZE21 B.The coating Mg F2 was used as the corrosion resistance layer,the dopamine polymer film(PDA)was used as the bonding layer,and HA was selected as the solvent of ASTA to graft astaxanthin(ASTA)onto the surface of ZE21 B.In this study,HA-ASTA coating was characterized by material science.The SEM and FTIR results show that the HA-ASTA coating was successfully prepared on the surface of the magnesium alloy,and there was no functional group change involved in the preparation process.The trans-polyene chain of ASTA still exists;the water contact angle results show that with the change of ASTA concentration The water contact angle presents a tendency to increase first and then decrease;the electrochemical test results show that the HA-ASTA group coatings all improve the corrosion resistance of magnesium alloys,and the p H value of the extract and the trend of the material weight loss test results are consistent with the electrochemical test results.The test is basically the same.The results of cytocompatibility experiments show that the HA-ASTA coating can improve the endothelial function of the magnesium alloy,accelerate the proliferation of endothelial cells,inhibit the proliferation of vascular smooth muscle cells,and reduce the number of adherent macrophages on the sample surface.Using hyaluronic acid-loaded rapamycin(RAPA)coating as the reference group,it was found that HAASTA-2 coating has better biocompatibility and is better than the coating containing rapamycin(RAPA).The experimental results of the hemolysis rate show that the HAASTA group samples improve the hemolysis performance of magnesium alloys and meet the requirements of biological materials for the hemolysis rate;the results of the fibrinogen adhesion and denaturation experiments on the surface of the HA-ASTA group samples are lower than those of magnesium The alloy group shows that the possibility of blood coagulation and thrombosis is low,and the platelet adhesion experiment also proves that the platelet adhesion on the surface of the HA-ASTA group sample is less,and the performance is better than that of the magnesium alloy.