Development of a novel functional core-shell-shell nanoparticles: From design to anti-bacterial applications

This article reports the synthesis and functionalization of a novel CuO@SiO₂-APTES@Ag⁰ core-shell-shell material using a simple and low-cost process. The growth, design strategies and synthesis approach are the key factors for the development of CuO@SiO₂-APTES@Ag⁰ as efficient material with enhanced antibacterial activity. We investigated the morphology, surface charge, structure and stability of our new core-shell-shell by atomic force microscopy, scanning electron microscopy, energy dispersive X-ray, Fourier transform infrared and UV-visible spectroscopies, zeta potential measurements, and differential scanning calorimetry. The covalent surface grafting of APTES (3-(aminopropyl)triethoxysilane) onto CuO@SiO₂ involving electrostatic interactions was confirmed. Size measurements and Scanning electron images showed that both APTES grafting and SiO₂/Ag shells dropped on the surface of CuO produced structural compaction. UV-Vis spectroscopy proved to be a fast and convenient way to optically detect SiO₂ shell on the surface of colloids. Additionally, the Ag-decorated CuO@SiO₂-APTES surfaces were found to possess antibacterial activity and thermally more stable than undecorated surfaces. CuO@SiO₂-APTES@Ag⁰ core-shell had antibacterial properties against Gram-positive bacteria making it a promising candidate for antibacterial applications.