Preparation of silver nanoparticles supported mesoporous silica microspheres with perpendicularly aligned mesopore channels and their antibacterial activities

Abstract

In this study, a facile and effective route for the preparation of silver nanoparticles supported surface mesoporous silica microspheres with perpendicularly aligned mesopore channels and their antibacterial activities were reported. The surface mesoporous silica microspheres (mSiO₂) were synthesized by a sol–gel method. The mSiO₂ were then functionalized with 3-aminopropyltriethoxysilane (APTS) to provide amino functional groups for the absorption of Ag⁺. Silver nanoparticles were directly created on the surface of mSiO₂ by in situ chemical reduction of the Ag precursor using an ultrasonic wave reaction method. The prepared silver nanoparticle supported surface mesoporous silica nanocomposites (mSiO₂@NH₂@Ag) were characterized with FT-IR, X-ray photoelectron spectroscopy, X-ray diffraction, scanning electron microscopy and high-resolution transmission electron microscopy. Antibacterial activities of the synthesized mSiO₂@NH₂@Ag were investigated against Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (SAU) using the conventional plate-count method. The results demonstrated that the synthesized nanocomposites exhibited excellent antibacterial properties against E. coli and SAU. Furthermore, because of the slow release property of silver, the synthesized nanocomposites can be used as an economic recyclable material in various antibacterial applications, such as water purification systems and environmental control of bacteria.