Microanatomy related biocidal activity at cellular resolution and bone reconstruction potential of PEG EGaIn nanocapsules

Critical bone defects, exacerbated by infections, pose significant challenges to bone healing and homeostasis, necessitating the development of dual-functional biomimetics that combine anti-infective and reparative capabilities. The EGaIn holds promise across various disciplines, though its interactions with microbial cells require further elucidation. This investigation evaluates the antimicrobial efficacy of PEG-EGaIn nanocapsules against a spectrum of bacterial, employing electron microscopy. Constructs containing 1.5% PEG-EGaIn hinder biofilm-producing bacteria, while 3% concentrations amplify the biocidal effect. Furthermore, the nanocapsules promoted osteogenic differentiation rBMSCs, evidenced by enhanced mineralization and upregulation of key osteogenic genes. In addressing large bone defects, PEG-EGaIn-Col-Ap-lamellar and ethanolic-mediated Col-Ap-lamellar constructs serve as potential solutions for bone resorption mitigation and osteo-angiogenesis. Bone-remodeling were validated through μ-CT and histomorphometry confirming no evidence of chronic inflammation or fibrosis. In this study, PEG-EGaIn nanocapsules emerge as potent biocide and bone repair, underscoring their potential in combating antibiotic resistance and enhancing bone healing.