Synthesis and characterization of gelzan nanocomposite scaffold incorporating Ag/Fe²⁺ co-doped hydroxyapatite for antibacterial bone tissue regeneration

Abstract A nanocomposite scaffold was developed using gelzan, a natural extracellular polysaccharide, as the biopolymer matrix. Gelzan (GZ) was combined with Ag/Fe 2 ⁺ co-doped hydroxyapatite (HAp) particles to enhance the scaffold’s biological properties. The aim of incorporating Ag/Fe 2 ⁺ co-doped HAp was to utilize the combined antibacterial and bioactive properties of these components. The synthesized Ag/Fe 2 ⁺ co-doped HAp nanoparticles, along with the gelzan-based nanocomposite scaffold produced via freeze-drying, underwent comprehensive analyses. These included Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and biological assessments for antibacterial activity and bioactivity. The results demonstrated that the Ag/Fe 2 ⁺ co-doped HAp nanocomposite scaffold possessed favourable physicochemical properties. Furthermore, the integration of Ag and Fe 2 ⁺ co-doped HAp into the gelzan matrix was confirmed, revealing the scaffold’s structural and compositional characteristics. Tests of apatite formation in simulated body fluid (SBF) indicated the development of layered apatite precipitates after 7 days. The scaffold also exhibited significant antibacterial activity, with inhibition zones of 7.35 ± 0.70 mm and 5.54 ± 0.60 mm against Staphylococcus aureus and Escherichia coli , respectively. These findings suggest the scaffold’s promising potential as a biomaterial for bone tissue regeneration.