Nonleaching Antibacterial Concept Demonstrated by In Situ Construction of 2D Nanoflakes on Magnesium

Abstract

In bone implants, antibacterial biomaterials with nonleaching surfaces are superior to ones based on abrupt release because systemic side effects arising from the latter can be avoided. In this work, a nonleaching antibacterial concept is demonstrated by fabricating 2D nanoflakes in situ on magnesium (Mg). Different from the conventional antibacterial mechanisms that depend on Mg2+ release and pH increase, the nanoflakes exert mechanical tension onto the bacteria membranes to destroy microorganisms on contact and produce intracellular stress via physical interactions, which is also revealed by computational simulations. Moreover, the nanoflake layer decelerates the corrosion process resulting in mitigated Mg2+ release, weaker alkalinity in the vicinity, and less hydrogen evolution, in turn inducing less inflammatory reactions and ensuring the biocompatibility as confirmed by the in vivo study. In this way, bacteria are killed by a mechanical process causing very little side effects. This work provides information and insights pertaining to the design of multifunctional biomaterials.

A Quantitative Bacteria Monitoring and Killing Platform Based on Electron Transfer from Bacteria to a Semiconductor

“…[ 1b,10 ] Since the mechanism does not involve chemical reagents, the potential toxicity and replenishment of antibacterial agents can be obviated. [ 11 ] Furthermore, it is highly desirable to design an antibacterial platform (materials) that can also serve as a quantitative bacteria sensor without involving tedious integration, but this type of rare “sense‐and‐treat” systems are frequently poorly designed and can hardly deliver the proper performance.…”

“…Stresses in various forms including physical interaction, [ 27 ] mechanical force, [ 11 ] and biochemicals [ 28 ] are exerted onto bacteria via either direct reaction or indirect interference mediated by the medium. Primary lesions take place first and activate the subsequent pathways modifying the physiological state of the bacteria on the protein and gene level.…”

A trilogy antimicrobial strategy for multiple infections of orthopedic implants throughout their life cycle

“…Thus, the antibacterial effect of Sr–Zn0@CaP group was not caused by the presence of Sr, suggesting that intrinsic property and morphology of CaP coating may contribute to the observed antimicrobial property. Many precious reports have confirmed that the unique topological morphology and corrugated surface structure could damage the microorganism through intrinsic bacteriostatic process [ 39 , [45] , [46] , [47] , [48] ]. In addition, increased surface roughness at the microscale significantly inhibit bacterial adhesion and biofilm formation on its surface [ 48 , 49 ].…”

“…After incubating at 37 °C for 1,3,6,12 and 18 h respectively, the alloy plates were fixed by 2.5% glutaraldehyde at 4 °C overnight, dehydrated sequentially by gradient ethanol (40, 60, 80, 90, 95, 98, and 100% v/v) gradually, and dried with a critical point drier. Finally, the samples were coated by gold before SEM observation [ 39 ] .…”

Improved Corrosion Resistance of Magnesium Alloy in Simulated Concrete Pore Solution by Hydrothermal Treatment

“…Rapid corrosion in aqueous solutions always hampers the applications of magnesium alloys in the automotive, aerospace, electronics industry, and biomedical field [ 1 – 6 ]. Nowadays, the concept of lightweight construction and equipment has been proposed for overcoming the energy and resources shortage in the development of our society [ 7 – 9 ].…”