Electrospun Scaffolds Containing Silver-Doped Hydroxyapatite with Antimicrobial Properties for Applications in Orthopedic and Dental Bone Surgery

Abstract

Preventing the development of osteomyelitis while enhancing bone regeneration is challenging, with relatively little progress to date in translating promising technologies to the clinic. Nanoscale hydroxyapatite (nHA) has been employed as a bone graft substitute, and recent work has shown that it may be modified with silver to introduce antimicrobial activity against known pathogens. The aim of this study was to incorporate silver-doped nHA into electrospun scaffolds for applications in bone repair. Silver-doped nHA was produced using a modified, rapid mixing, wet precipitation method at 2, 5, 10 mol.% silver. The silver-doped nHA was added at 20 wt.% to a polycaprolactone solution for electrospinning. Bacteria studies demonstrated reduced bacterial presence, with Escherichia coli and Staphylococcus aureus undetectable after 96 h of exposure. Mesenchymal stem cells (MSCs) were used to study both toxicity and osteogenicity of the scaffolds using PrestoBlue® and alkaline phosphatase (ALP) assays. Innovative silver nHA scaffolds significantly reduced E. coli and S. aureus bacterial populations while maintaining cytocompatibility with mammalian cells and enhancing the differentiation of MSCs into osteoblasts. It was concluded that silver-doped nHA containing scaffolds have the potential to act as an antimicrobial device while supporting bone tissue healing for applications in orthopedic and dental bone surgery.

Silver ion‐doped calcium phosphate‐based bone‐graft substitute eliminates chronic osteomyelitis: An experimental study in animals

“…Korkusuz et al 36 reported that parenteral antibiotics and surgical debridement alone or combined with antibiotic‐impregnated bone cement failed to eliminate infections and that locally implanted antibiotic‐impregnated hydroxyapatite succeeded in treating osteomyelitis in rats even when metal implants were not removed. With the advancing technology, nano‐sized systems have begun to find a place among biodegradable carriers 37 . It was suggested that nano‐sized calcium phosphate might be the most natural agent for local antibiotic transfer 38 .…”

“…These conditions are mainly related to the form of the silver and long‐term accumulation of silver 22,23 . In recent years, double‐action silver‐added calcium phosphate combinations developed for the treatment of bone infections have been published 37,44 . Paterson et al 37 developed electrospun PCL scaffolds containing silver‐doped hydroxyapatite with antimicrobial properties and examined in‐vitro.…”

Clinical Application of Bone Marrow Mesenchymal Stem/Stromal Cells to Repair Skeletal Tissue

“…This was addressed by modifying nanoscale HA with sliver, which is known to have antimicrobial properties, and combining with an electrospun scaffolds. As a proof-of-concept study this scaffold was shown to be non-toxic to rat BMSC and improved osteogenic differentiation capacity of cultured BMSC, while significantly reducing bacterial populations [ 86 ]. Using a similar concept, ZnO/nanocarbon modified fibrous scaffolds have demonstrated osteogenic and antibacterial properties, albeit in vitro [ 87 ].…”

An Updated Review on Silver Nanoparticles in Biomedicine

“…Silver nanorods incorporated within highly porous wollastonite scaffolds determined strong bactericidal effects while providing the favorable apatite-forming ability and good cytocompatibility with respect to osteoblast-like cells [ 326 ]. Composite freeze-thawed gelatin/alginate/PVA and electrospun PCL scaffolds embedded with a bactericidal concentration of silver-HAp nanoparticles showed suitable porosity and prolonged release metallic ions, with simultaneous favorable adhesion, proliferation and osteogenic potential on mammalian cells [ 327 , 328 ].…”