Antimicrobial Nanocomposites Based on Oxidized Cotton Fabric and in situ Biosynthesized Copper Oxides Nanostructures Using Bearberry Leaves Extract

The aim of this study was to develop antimicrobial nanocomposite textile material comprising of Cu-based nanostructures synthesized on oxidized cotton fabric using Arctostaphylos uva-ursi (L.) Spreng., Ericaceae (bearberry leaves) as a green reducing agent for adsorbed Cu2+-ions. In order to provide sufficient number of carboxyl groups for complexation with Cu2+-ions a two-step oxidation process with NaIO4 and NaClO2 was carried out. The influence of NaIO4 concentration on content of carboxyl groups and Cu-based nanoparticles was studied by FTIR and AAS. HPLC analysis identified the gallic acid known as a reducing agent in bearberry leaves extract. FESEM and XRD analyses revealed that using bearberry leaves extract and gallic acid solution as reducing agents led to a formation of spherical Cu2O/CuO nanoparticles and CuO nanosheets, respectively. These nanoparticles and nanosheets provided excellent antibacterial activity against Gram-negative bacteria Escherichia coli and Gram-positive bacteria Staphylococcus aureus. Cytotoxicity on human keratinocyte cells was shown to depend on their copper content.