Synthesis of MPTMS surface modified silica-silver nanocomposite particles and their potent antibacterial properties

Abstract

Recently, metal-inorganic composite material research has drawn significant research attention. These studies are aimed to adjust the morphology and behavior of nanoparticles included extending the utilization field of the particles. Synthesis of silica is one of the research areas actively performed in many industries. It can be synthesized by using the surface-modified silica composite materials with various properties, and they are useful in various applications. In this study, preparation of silica composite materials having a variety of properties was conducted to focus on the antibacterial nature. In chapter 1, silica nanoparticles were prepared through sol-gel process through Stöber method with MTPMS. The surface of silica was modified with S-H and alcohol reduction process produced the composite materials, which was the silica-silver nanocomposite particles. Surface characterizations of silica-silver nanocomposite particles using AgNO3 and AgBF4 and silica nanoparticles were prepared in different temperature. Also, the composite materials are synthesized depending on different silver concentrations. Finally, the formation mechanism was shown in brief. In chapter 2, research regarding to several applications included antimicrobial properties that could be utilized by composite materials was carried out. First, silicone elastomer film was prepared by using silicone elastomer kit consisted of initiators (silicone elastomer base) and curing agent. Untreated bare film (bare film) type, silver nanoparticles film (silver film) type, silica-silver nanocomposite particles film (silica-silver film) type were prepared through spin coating and thermal treatment on the glass. The antibacterial properties of each film were evaluated through JIS Z 2801 method. Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus) were used in the evaluation. Through the test results, bare film did not show any antibacterial activity but the antibacterial efficiency of silica-silver film was proved to have the same antibacterial efficiency of silver film, which is 99.99 %. Finally, antibacterial activity of silver ion films was studied depending on concentration of silver ion.