Corrosion resistance and antibacterial activity of zinc-loaded montmorillonite coatings on biodegradable magnesium alloy AZ31

et al. 2020

Coatings

As a revolutionary implant material, magnesium and its alloys have many exciting performances, such as biodegradability, mechanical compatibility, and excellent biosecurity. However, the rapid and uncontrollable degradation rate of magnesium greatly hampers its clinical use. Many efforts have been taken to enhance the corrosion resistance of magnesium. However, it must be noted that improving the corrosion resistance of magnesium will lead to the compromise of its antibacterial abilities, which are attribute and proportional to the alkaline pH during its degradation. Providing antibacterial functionalized coating is one of the best methods for balancing the degradation rate and the antibacterial ability of magnesium. Antibacterial functionalized magnesium is especially well-suited for patients with diabetes and infected wounds. Considering the extremely complex biological environment in the human body and the demands of enhancing corrosion resistance, biocompatibility, osteogenesis, and antibacterial ability, composite coatings with combined properties of different materials may be promising. The aim of this review isto collect and compare recent studies on antibacterial functionalized coatings on magnesium and its alloys. The clinical applications of antibacterial functionalized coatings and their material characteristics, antibacterial abilities, in vitro cytocompatibility, and corrosion resistance are also discussed in detail.

Section: In Vitro Cytocompatibilitymentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Advances in Antibacterial Functionalized Coatings on Mg and Its Alloys for Medical Use—A Review

Zhang

et al. 2020

Coatings

“…Zn 2+ tends to bind to nitrogen and sulfur atoms in histidine and cysteine residues of proteins, leading to little existence of free Zn [ 55 ]. Zn 2+ was reported to possess comparatively higher antibacterial property but less damaging to DNA or the immune system compared to Ag + [ 28 ]. Yu et al used plasma immersion ion implantation to co-implant Zn 2+ and Mg 2+ on titanium dental implant surfaces.…”

Section: Chemical Treatments With Metallic Agentsmentioning

confidence: 99%

“…On Mg alloy AZ31, Zou et al loaded Zn 2+ on montmorillonite (MMT) via a hydrothermal approach for the sustained release of Zn 2+ . Zn-MMT coating exhibited significant antibacterial activity, inhibiting the growth of S. aureus and E. coli significantly [ 28 ].…”

Section: Chemical Treatments With Metallic Agentsmentioning

confidence: 99%

Metallic Antibacterial Surface Treatments of Dental and Orthopedic Materials

et al. 2020

The oral cavity harbors complex microbial communities, which leads to biomaterial-associated infections (BAI) during dental and orthopedic treatments. Conventional antibiotic treatments have met great challenges recently due to the increasing emergency of drug-resistant bacteria. To tackle this clinical issue, antibacterial surface treatments, containing surface modification and coatings, of dental and orthopedic materials have become an area of intensive interest now. Among various antibacterial agents used in surface treatments, metallic agents possess unique properties, mainly including broad-spectrum antibacterial properties, low potential to develop bacterial resistance, relative biocompatibility, and chemical stability. Therefore, this review mainly focuses on underlying antibacterial applications and the mechanisms of metallic agents in dentistry and orthopedics. An overview of the present review indicates that much work remains to be done to deepen the understanding of antibacterial mechanisms and potential side-effects of metallic agents.

“…Moreover, such phenomenon signifies that Mg-based alloys will lose their expected inherent function. The rapid and uncontrollable corrosion rate of Mg-based alloys leads to hydrogen evolution and high local alkalization, which tend to cause great challenges in tissue reconstruction [ [19] , [20] , [21] ]. Thus, controlling the degradation rate of the Mg-based alloys is essential in their clinical application.…”

Section: Introductionmentioning

confidence: 99%

Photo-controlled degradation of PLGA/Ti3C2 hybrid coating on Mg-Sr alloy using near infrared light

Huang

et al. 2021

Bioactive Materials

A PLGA/Ti 3 C 2 hybrid coating was successfully deposited on the surface of magnesium-strontium (Mg-Sr) alloys. Compared with the corrosion current density ( i corr ) of the Mg-Sr alloy (7.13 × 10 −5 A/cm 2 ), the modified samples (Mg/PLGA/Ti 3 C 2 ) was lower by approximately four orders of magnitude (7.65 × 10 −9 A/cm 2 ). After near infrared 808 nm laser irradiation, the i corr of the modified samples increased to 3.48 × 10 −7 A/cm 2 . The mechanism is that the local hyperthermia induced the free volume expansion of PLGA, and the increase in intermolecular gap enhanced the penetration of electrolytes. Meanwhile, the cytotoxicity study showed that the hybrid coating endowed the Mg-Sr alloy with enhanced biocompatibility.