The sol-gel synthesis of cotton/TiO₂ composites and their antibacterial properties

Present work is devoted to investigation of structure and functional properties of hybrid nanomaterials based on the TiO₂-modified cellulose fibers of cotton. The titania hydrosol was successfully prepared using the titanium tetraisopropoxide as precursor and the nitric acid as peptizing agent via the low-temperature sol-gel synthesis in aqueous medium and applied to cotton fabric. For cross-linking of titania nanoparticles to cotton the 1,2,3,4-butanetetracarboxylic acid (BTCA) was used as a spacer. The morphology and composition of the surface pure and TiO₂ modified cotton fibers were investigated by the scanning electron microscopy (SEM). The cotton/TiO₂ composite was characterized by the dielectric permittivity. For the estimation of total titania concentration, all samples were calcined at 650°C. The antimicrobial activity of the treated TiO₂ cotton fibers was investigated against Escherichia coli as a model Gram-negative bacteria after exposure to UV-irradiation for 10min.