Two completely different biomimetic reactions mediated by the same matrix producing inorganic/organic/inorganic hybrid nanoparticles

Abstract An environment friendly procedure for the preparation of inorganic/organic/inorganic i.e. silica/hyperbranched poly(ethyleneimine) (PEI)/silver nanoparticles employing two biomimetic reactions is described. Silver ions can be absorbed into the hyperbranched PEI cavities and undergo reduction without employing a reducing agent. This is a process mimicking biomineralization, realized by specific proteins in some microorganisms. Dendritic poly(ethyleneimine) possesses size and functions that are similar to proteins and thus presents an ideal alternative to their role by mimicking their catalytic activity. At the periphery of PEI another procedure mimicking biosilicification can also be performed due to the presence of amino groups mimicking another category of proteins. To our knowledge this is the first example of a combination of two different biomimetic reactions performed by a single molecule in one pot synthesis procedure. The resulting hybrid nanoparticles are characterized by spectroscopy (FTIR, visible), thermogravimetry (TG), scanning electron microscopy (SEM), dynamic light scattering (DLS) X-ray diffraction, Energy-dispersive X-ray spectroscopy. Their antibacterial activity was assessed towards Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus .