Abstract
Orthopaedic infection with bacteria leads to high societal cost and is detrimental to the life quality. Particularly, deep bone infection leading to osteomyelitis results in an inflammatory response whereby localized bone destruction occurs. Current treatments like antibiotic-containing polymethymethacrylate (PMMA) still has the high risk of bacterial resistance. Taking advantages of silver which has antibacterial and anti-inflammatory effect and bioactive collagen, we fabricated a silver nanoparticle (AgNP)-coated collagen membrane by sonication and sputtering. SEM showed good deposition of AgNPs on collagen membrane by both coating methods. The optimal coating concentration was finalized by assessing optimal antibacterial effect against cytotoxicity and finally collagen membrane coated with 1mg/mL AgNPs solution was selected. We also found that the coated collagen membrane demonstrating short-term cytotoxicity within 24 hours with damage to the cell membrane, which was evidenced by MTS and LDH release test, but had no significant influence (p > 0.05) thereafter. The amount of released AgNPs from coated collagen membrane had negligible cytotoxicity (p > 0.05). Confocal laser scanning microscope displayed similar cell morphology in both coated and uncoated collagen membrane. ELISA and qPCR presented the decreased secretion and expression (p < 0.001) of IL-6 and TNF-alpha. Upregulated expression (p < 0.001) of osteogenesis markers (RUNX2, ALP and OPN) could be found and this might be attributed to the modified collagen fibre surface coated by AgNPs. Collectively, the osteogenesis induced by AgNPs demonstrates a promising application in orthopaedic surgery for its use both as an antimicrobial agent, and to enhance bone regeneration.
