Preparing a Bioactive (Chitosan/Sodium Hyaluronate)/SrHA Coating on Mg–Zn–Ca Alloy for Orthopedic Implant Applications

• Published in: Frontiers in materials Vol. 8
• Main Authors: Feng, Yashan, Chang, Lei, Zhu, Shijie, Yang, Yongxin, Wei, Baoli, Lv, Meng, Wang, Jun, Guan, Shaokang
• Format: Journal Article
• Language: English
• Published: Frontiers Media S.A 10.01.2022
• Subjects: antibacterial; bioactive; chitosan; Mg alloys; SrHA
• ISSN: 2296-8016; 2296-8016
• DOI: 10.3389/fmats.2021.823506

The uncontrollable rapid degradation rate of the Mg alloy substrate limited its clinical application, and implant-associated infections have been reported to be the main reason for the secondary surgery of orthopedic implantation. The aim of this study was to produce a multifunctional coating on magnesium-based alloys that have improved corrosion resistance, bioactivity, and antibacterial properties through the preparation of polyelectrolytic multilayers (PEMs) consisting of chitosan (CS) and sodium hyaluronate (HA) on silane-modified strontium-substituted hydroxyapatite (hereafter referred to as Bil (SH + CS)/SrHA). The multifunctional coatings were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy (XPS). The results showed the polyelectrolyte complex SH/CS layer to be uniformly and tightly attached on to the surface of silane-treated SrHA. At the same time, a potentiodynamic polarization test and hydrogen evolution test showed the Bil (SH + CS)/SrHA coatings to exhibit superior corrosion resistance than bulk Mg-based alloys. The results of the cell–surface interactions revealed Bil (SH + CS)/SrHA coatings to be in favor of cell initial adhesion and more beneficial to the proliferation and growth of cells with the processing of co-culture. In addition, antibacterial tests demonstrated the strong bactericidal effect of Bil (SH + CS)/SrHA coatings against both Escherichia coli ( E. coli ) and Staphylococcus ( S. aureus ), suggesting that Bil (SH + CS)/SrHA coatings can successfully achieve multifunctionality with enhanced corrosion resistance, biocompatibility, and antibacterial properties.