Surface modification of biodegradable magnesium alloy with poly (L-lactic acid) and sulfonated hyaluronic acid nanoparticles for cardiovascular application

Abstract

Magnesium (Mg) and its alloys have attracted extensive attention of researchers in the field of cardiovascular implants due to their good mechanical properties and biosafety. Constructing a multifunctional hybrid coating seems to be an effective strategy to address the insufficient endothelialization and poor corrosion resistance of Mg alloy vascular stents. In this study, a dense layer of magnesium fluoride (MgF2) was prepared on the surface of Mg alloy aiming at better corrosion resistance; Thereafter, sulfonated hyaluronic acid (S-HA) was made into small sized nanoparticles (NP) which were deposited on the MgF2 surface by self-assembly method, followed with poly-L-lactic acid (PLLA) coating preparation by one-step pulling method. The blood and cell tests showed that the composite coating had good blood compatibility, pro-endothelial, anti-hyperplasia and anti-inflammatory functions. Compared to current clinical PLLA@ Rapamycin coating, our PLLA/NP@S-HA coating showed better functions of promoting endothelial cells growth. These results strongly furnished a promising and feasible strategy for the surface modification of Mg-based degradable cardiovascular stents.