Synthesis and Characterization of Dual-functionalized Metal-Phyllosilicates for Antibacterial Applications

摘要

Dual-functionalized organoclays containing thiol and amine groups were synthesized by one-step sol-gel process.Individual organoclays differed significantly in the sequential order of organic groups and sil-anol/thiol contents.Their sulfur contents could be adjusted by the mercaptopropyl-feed ratios.NMR studies showed that silanol was more abundant in calcium-based clays than in magnesium-based clays.The interlayer distances in organoclays is inversely proportional to the number of thiol groups.As the thiol content in the silicates increased,the thermal stabilities increased up to 273 °C for thiol-functionalized Mg-based clay and 298 °C for Ca-based clay.Antibacterial activity of the dual-functionalized metal-phyllosilicates was greater against Streptococcus mutans than against Escherichia coli and Lactobacillus salivarius,and their minimal inhibitory concentrations were possibly related with water-dispersibility and thiol content.Accordingly,these metal-phyllosilicates are promising for technological applications in many fields such as pharmaceuticals,biomedical engineering,polymer composite engineering industries.