Alginate-Xanthan Nanocomposite Scaffolds Incorporating Copper-Doped Bioactive Glass for Novel Tissue Engineering Potential in Regenerative Endodontics

This study aimed to design, fabricate, and characterize a novel nanocomposite scaffoldAQ based on alginate-xanthan, incorporating copper-doped bioactive glass nanoparticles, for potential applications in regenerative endodontics. Bioactive glass nanoparticles with varying copper concentrations (0(B0), 0.5(B0.5), 2.5(B2.5), and 5(B5) wt%) were synthesized using the sol-gel method. Subsequently, scaffolds (pristine alginate-xanthan (A-X) and those incorporating the various copper-doped bioactive glasses (A-XB0, A-XB0.5, A-XB2.5 and A-XB5)) were fabricated via 3D printing. The synthesized nanoparticles and scaffolds were characterized by Fourier Transform Infrared Spectroscopy (FTIR) for chemical bonds and functional groups; Energy-Dispersive X-ray Spectroscopy (EDS) for elemental composition; X-ray Diffraction (XRD) for crystalline/amorphous structure; Scanning Electron Microscopy (SEM) for morphological and surface analysis; and Dynamic Light Scattering (DLS) for particle size and distribution. Subsequently, their hemocompatibility, antioxidant properties, and biodegradation were evaluated to assess their biological capabilities. The A-XB2.5 scaffold exhibited desirable surface roughness (by creating nano/micro fibers) and a well-distributed nanoparticle structure. The FTIR and EDS analyses confirmed the successful incorporation of copper into the bioactive glass structure, while XRD revealed an amorphous nature of the nanoparticles. Hemocompatibility tests indicated that the A-XB2.5 scaffold exhibited the lowest hemolysis rate, suggesting excellent blood compatibility. Antioxidant assays revealed that the A-XB2.5 scaffold exhibited the highest free radical scavenging activity, which decreased at higher copper concentrations due to potential oxidative stress. Degradation studies showed that the A-XB5 scaffold had the lowest degradation rate, indicating enhanced structural stability. This study successfully synthesized and characterized a novel alginate-xanthan nanocomposite scaffold containing copper-doped bioactive glass and investigated how copper concentration impacts its properties. We found that the A-XB2.5 scaffolds provided the most favorable characteristics, including uniform nanoparticle distribution, desirable surface roughness (by creating nano/micro fibers), enhanced antioxidant properties, and excellent hemocompatibility. In contrast, A-XB5 scaffolds led to significant nanoparticle aggregation, reduced antioxidant properties, and increased hemolysis, indicating potential copper toxicity at elevated levels. These findings highlight the dual role of copper (beneficial at optimal doses and detrimental at higher concentrations) in biomaterial design.

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