Improved Bacteriostatic and Anticorrosion Effects of Polycaprolactone/Chitosan Coated Magnesium via Incorporation of Zinc Oxide

Abstract

Magnesium has been recognized as a groundbreaking biodegradable biomaterial for implant applications, but its use is limited because it degrades too quickly in physiological solutions. This paper describes the research on the influence of polycaprolactone (PCL)/chitosan (CS)/zinc oxide (ZnO) composite coating (PCL/CS/ZnO) on the corrosion resistance and antibacterial activity of magnesium. The PCL/CS film presented a porous structure with thickness of about 40–50 μm, while after incorporation of ZnO into the PCL/CS, a homogenous film without pores and defects was attained. The ZnO embedded in PCL/CS enhanced corrosion resistance by preventing corrosive ions diffusion in the magnesium substrate. The corrosion, antibacterial, and cell interaction mechanism of the PCL/CS/ZnO composite coating is discussed in this study. In vitro cell culture revealed that the PCL/CS coating with low loaded ZnO significantly improved cytocompatibility, but coatings with high loaded ZnO were able to induce some cytotoxicity osteoblastic cells. It was also found that enhanced antibacterial activity of the PCL/CS/ZnO coating against both Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) bacteria, while less significant antibacterial activity was detected for uncoated Mg and PCL/CS coating. Based on the results, the PCL/CS coatings loaded with low ZnO content may be recommended as a candidate material for biodegradable Mg-based orthopedic implant applications.

Fabrication and characterization of polycaprolactone/chitosan nanofibers containing antibacterial agents of curcumin and ZnO nanoparticles for use as wound dressing

“…ZnO nanoparticles had different effects on the antibacterial activity of the scaffolds against bacteria, increasing antibacterial activity against E. coli while decreasing antibacterial effectiveness against S. aureus. It means that ZnO had a better performance against E. coli bacteria, which is due to their thin-walled nature (Bakhsheshi-Rad et al, 2021;Keyvani et al, 2021). Incorporation of Cur to PCL15CS3ZnO1 produced greater antibacterial activity against both bacteria.…”

Progress in bioactive surface coatings on biodegradable Mg alloys: A critical review towards clinical translation

“…The reinforcement provided by inorganic particles results in improved mechanical properties. Bakhsheshi-Rad et al [ 367 ] dip coated a noble PCL/Chitosan composite coating on Mg. An additional ZnO layer was applied to seal the microdefects, which significantly improved the corrosion resistance and anti-bacterial properties of the coating. However, at higher concentrations, ZnO exhibited cytotoxicity towards osteoblast cells.…”

Nanotechnology in the service of corrosion science: considering graphene and derivatives as examples

“…Among the metal nanopowders, zinc, titanium and aluminium nanopowders are very commonly employed. Among the metal oxide nanofillers, nano-silica (SiO 2 ) [110][111][112][113], nano-titania (TiO 2 ) [114][115][116][117][118][119], nanoalumina (Al 2 O 3 ) [120][121][122], nano-zinc oxide (ZnO) [123][124][125][126][127], nano-zirconia (ZrO 2 ) [128][129][130][131], nano-cerium oxide (CeO 2 ) [132][133][134][135] and nano-iron oxide (Fe 2 O 3 and Fe 3 O 4 ) [135][136][137][138] are the very commonly used and detailed description on their nanofiller effect can be found elsewhere [109]. Recently, Steffi et al [139] developed a tertiary composite based on graphitic carbon nitride-Silica-Titania (gC 3 N 4 / SiO 2 /TiO 2 ) and tested its anticorrosion potential for mild steel in 3.5% NaCl.…”