Antimicrobial Polymeric Composites with Embedded Nanotextured Magnesium Oxide

Abstract

Nanotextured magnesium oxide (MgO) can exhibit both antibacterial and tissue regeneration activity, which makes it very useful for implant protection. To successfully combine these two properties, MgO needs to be processed within an appropriate carrier system that can keep MgO surface available for interactions with cells, slow down the conversion of MgO to the less active hydroxide and control MgO solubility. Here we present new composites with nanotextured MgO microrods embedded in different biodegradable polymer matrixes: poly-lactide-co-glycolide (PLGA), poly-lactide (PLA) and polycaprolactone (PCL). Relative to their hydrophilicity, polarity and degradability, the matrices were able to affect and control the structural and functional properties of the resulting composites in different manners. We found PLGA matrix the most effective in performing this task. The application of the nanotextured 1D morphology and the appropriate balancing of MgO/PLGA interphase interactions with optimal polymer degradation kinetics resulted in superior bactericidal activity of the composites against either planktonic E. coli or sessile S. epidermidis, S. aureus (multidrug resistant-MRSA) and three clinical strains isolated from implant-associated infections (S. aureus, E. coli and P. aeruginosa), while ensuring controllable release of magnesium ions and showing no harmful effects on red blood cells.

Antimicrobial polymeric composites for high-touch surfaces in healthcare applications

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Improvement of the mechanical properties and osteogenic activity of 3D-printed polylactic acid porous scaffolds by nano-hydroxyapatite and nano-magnesium oxide

“…At the molecular level, magnesium ions are involved in various enzymatic reactions in cells and can indirectly encourage cell mineralization by increasing the activity of alkaline phosphates (C. Feng et al., 2017 ; Lin et al., 2018 ; Park et al., 2010 ; Serre et al., 1998 ; Tarafder et al., 2013 ). In addition, it has been shown that the incorporation of MgO into PLA can significantly increase the activity of osteoblasts and can effectively inhibit the value-added of osteoclasts, providing a good physiological basis for bone regeneration, in addition to the powerful antibacterial activity that MgO provides to PLA( Aničić et al., 2021 ). Other common dopants of PLA composites are ZnO and CuO, among others.…”

LL-37-Coupled Porous Composite Scaffold for the Treatment of Infected Segmental Bone Defect

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