Dual Synergistic Effects of MgO-GO Fillers on Degradation Behavior, Biocompatibility and Antibacterial Activities of Chitosan Coated Mg Alloy

Abstract

The aim of this work was to establish and characterize chitosan/graphene oxide- magnesium oxide (CS/GO-MgO) nanocomposite coatings on biodegradable magnesium-zinc-cerium (Mg-Zn-Ce) alloy. In comparison to that of pure CS coatings, all composite coatings encapsulating GO-MgO had better adhesion strength to the Mg-Zn-Ce alloy substrate. The result depicted that the co-encapsulation of GO-MgO into the CS layer leads to diminish of contact angle value and hence escalates the hydrophilic characteristic of coated Mg alloy. The electrochemical test demonstrated that the CS/GO-MgO coatings significantly increased the corrosion resistance because of the synergistic effect of the GO and MgO inside the CS coating. The composite coating escalated cell viability and cell differentiation, according to cytocompatibility tests due to the presence of GO and MgO within the CS. The inclusion of GO-MgO in CS film, on the other hand, accelerates the formation of hydroxyapatite (HA) during 14 days immersion in SBF. Immersion results, including weight loss and hydrogen evolution tests, presented that CS/GO-MgO coating enables a considerably reduced degradation rate of Mg-Zn-Ce alloy when compared to the bare alloy. In terms of antibacterial-inhibition properties, the GO-MgO/CS coatings on Mg substrates showed antibacterial activity against Escherichia coli (E. coli), with a large inhibition area around the specimens, particularly for the coating containing a higher concentration of GO-MgO. Bacterial growth was not inhibited by the bare Mg alloy samples. The CS/GO-MgO composite coating is regarded as a great film to enhance the corrosion resistance, bioactivity, and antibacterial performance of Mg alloy implants.

Chitosan/PVA/PEG Blend Strengthened with MgO Nanoparticles for Antibacterial Application

“…The antibacterial effect of MgO may result a damage to the peptide linkages at super-oxide ions on the carbonyl group, which causes degradation the protein of the pathogens. MgO reacts with intracellular oxygen to create reactive oxygen species ROS such as O2 •-, OH • and H2O2 which could be delivered into the medium [36] and then motivates the destructive efficiency towards the bacterial cell wall [37]. The results revealed that the CHT hybridized with polymeric agents and MgO nanopowder did not exhibit a significant antibacterial efficiency against gram negative strains as compared with gram positive ones.…”

Surface engineering of pure magnesium in medical implant applications

“…In the realm of future surface modification for pure Mg and Mg alloys, the exploration of composite coatings is regarded as a pivotal research avenue compared to single coatings [ [94] , [95] , [96] , [97] ]. In 2018, Feng Peng and collaborators achieved the creation of a superhydrophobic, highly adhesive coating on pure Mg surfaces using a straightforward one-step method, drawing inspiration from the “petal effect” [ 80 ].…”

Flexible Free-Standing Graphene-Fe2O3 Hybrid Paper with Enhanced Electrochemical Performance for Rechargeable Lithium-Ion Batteries

“…Graphene paper (GP) and its different kinds of derivatives have been successfully prepared by filtrating graphene nanosheets and are directly used as the electrode materials of flexible energy storage devices without any conductive additives and binder [6]. The free-standing GP and its various derivatives electrodes can improve the electrical conductivity and achieve higher active material-to-substrate mass ratios compared with the traditional electrodes [7].…”