Synthesis and characterization of silver nanoparticles-doped hydroxyapatite/alginate microparticles with promising cytocompatibility and antibacterial properties

In this paper, a facile double-emulsion approach was reported to fabricate the silver nanoparticles (AgNPs)-doped hydroxyapatite/alginate nanocomposite microparticles. First, hydroxyapatite nanoparticles (HApNPs) were prepared using coprecipitation method, then, HApNPs were involved in sodium alginate (Alg) network to form HAp/Alg microparticles via emulsion process. Next, silver nitrate was involved into HAp/Alg microparticles using second emulsion, which ascorbic acid was used as a trigger to form in situ-AgNPs-doped HAp/Alg microparticles. Physicochemical properties of the nanocomposite microparticles were characterized by Transmission Electron Microscopy (TEM), Fourier Transform Infrared (FT-IR) spectra, Dynamic Light Scattering (DLS), Ultraviolet-Visible (UV-vis) Absorption Spectra, and Thermogravimetric analysis (TG). It was demonstrated that AgNPs and HApNPs were evenly distributed in entire microparticles (diameter similar to 550 nm). Furthermore, the AgNPs-doped HAp/Alg microparticles showed a good cytocompatibility by culturing with A549 cells. Finally, the microparticles displayed an excellent antibacterial activity against Gram-negative E. coli and Gram-positive S. aureus. Above results manifested the significance of the final microparticles in diverse biomedical applications.