Bactericidal activity of cotton fabrics functionalized by ZnO and Cu via microwave

In this work, we developed bactericidal cotton fabrics treated with ZnO and Cu2+, with citric acid as a binder and reduction agent, via microwave irradiation. Fabrics were characterized by thermogravimetric analysis, FT-Raman, Fourier-transform infrared spectroscopy (FTIR), x-ray diffractometry, dynamic light scattering, scanning electron microscopy, X-ray photoelectron spectroscopy, and antibacterial activity against Bacillus subtilis and Escherichia coli. FT-Raman and FTIR results indicated bonding and electrostatic interaction between the nanoparticles (NPs) and the fabrics, more intense for the highest binder concentrations. The SEM images confirm the efficient incorporation of NPs in the cotton fabric, prepared by a low-cost and straightforward methodology that uses microwave irradiation and a low-cost and environmentally friendly binder. Besides, citric acid acted as a modifier of the crystalline structure of cellulose, depending on its concentration. The easily identifiable copper and zinc oxide particles on the surface of cotton fibers are responsible for their antimicrobial activity.