Author: Fathima Shana Pattar Kadavan
Pattar Kadavan, Fathima Shana, 2024 Antibacterial activity and biocompatibility of bioactive coatings of silver gallium nano-amalgamated particles on bioceramics, Flinders University, College of Medicine and Public Health
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Implant-associated infections remain a significant challenge in orthopaedic surgeries, often complicating recovery and affecting the longevity of the implants. Innovative solutions are necessary to address these concerns effectively. Hydroxyapatite (HAp) is known commonly bioactive ceramics with biocompatibility but is susceptible to bacterial colonisation. This study aimed to develop an innovative antibacterial bioceramic by coating HAp with silver-gallium nano-amalgamated particles (Ag-GaNPs), creating a new material (HAp-Ag-GaNPs) with effective antibacterial properties against pathogens causing osteomyelitis while maintaining biocompatibility. HAp discs were coated Ag-GaNPs through a dip-coating process. HAp-Ag-GaNPs were characterised using SEM-EDS and XRD analyses to confirm successful fabrication and coating. The antibacterial efficacy was tested against common pathogens such as Gram-positive Staphylococcus aureus and Gram-negative Pseudomonas aeruginosa. Antibacterial mechanisms were assessed through SEM imaging, ROS assays, and cellular leakage assessments. Biocompatibility with mammalian cells was examined using MG63 osteosarcoma cell viability and proliferation studies. The HAp-Ag-GaNPs exhibited significant antibacterial activity, achieving over 96% effectiveness initially and maintaining 85% effectiveness after 24 hours. SEM revealed significant structural damage to bacterial cells, with HAp-Ag-GaNPs compromising bacterial integrity and increasing ROS production, leading to cellular leakage of nucleic acids and proteins. Furthermore, the coatings promoted cell proliferation and supported mineralisation, indicating strong biocompatibility. Overall, HAp-Ag-GaNPs represent a novel bioceramic material. By integrating antimicrobial efficacy with essential biological compatibility, these coatings offer a promising strategy to redefine bioceramics, providing a new standard for next-generation orthopaedic implants addressing the critical need for infection prevention in orthopaedic surgeries.
Keywords: Hydroxyapatite, Bioceramic, Silver-gallium nano-amalgamated particles, Implant-associated infections, Antibacterial activity, Biocompatibility
Subject: Medical Biotechnology thesis
Thesis type: Masters
Completed: 2024
School: College of Medicine and Public Health
Supervisor: Dr Vi Khanh Truong