Preparation, Characterization, and Antibacterial Properties of Cu-Fibreboards

Lyubomir Aleksandrov; Nadezhda Rangelova; Nevena Lazarova-Zdravkova; Nelly Georgieva; Mirela Dragnevska; Sanchi Nenkova

doi:10.3390/ma16216936

Preparation, Characterization, and Antibacterial Properties of Cu-Fibreboards

Materials (Basel). 2023 Oct 28;16(21):6936. doi: 10.3390/ma16216936.

Authors

Lyubomir Aleksandrov¹, Nadezhda Rangelova², Nevena Lazarova-Zdravkova³, Nelly Georgieva³, Mirela Dragnevska⁴, Sanchi Nenkova⁴

Affiliations

¹ Institute of General and Inorganic Chemistry, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria.
² Department of Industrial Safety, University of Chemical Technology and Metallurgy, 1756 Sofia, Bulgaria.
³ Department of Biotechnology, University of Chemical Technology and Metallurgy, 1756 Sofia, Bulgaria.
⁴ Department of Pulp, Paper and Printing Arts, University of Chemical Technology and Metallurgy, 1756 Sofia, Bulgaria.

Abstract

In the present study, copper modified fibreboards were prepared and their existing phase, morphology, and antibacterial behaviour were investigated. The copper content and the physical and mechanical properties of fibreboards (thickness, bending strength, and swelling) were determined. X-ray diffraction analysis (XRD) showing diffraction peaks typical for cellulose, Cu₂S, and Na₂SO₄, depended on the preparation conditions. The average size of the Cu₂S crystals varied between 20 and 50 nm. The morphology of the obtained fibreboards, as well as the size and shape of copper particles, were observed by scanning electron microscopy (SEM) and transition electron microscopy (TEM). The antibacterial activity was tested against Gram-positive (Bacillus subtilis 3562) and Gram-negative (Escherichia coli K12 407) bacteria. The tests showed that the materials had higher antibacterial activity against E. coli, which depended on their preparation conditions. Based on these results, the obtained copper fibreboards can be used as antibacterial agents in the packaging and building industry.

Keywords: antibacterial activity; copper nanoparticles; fibreboards; modification.

Grants and funding

The authors acknowledge to the TwinTeam project Д01-272 “European Network on Materials for Clean Technologies” for providing the opportunity to present the results at SizeMat4 conference as well as for the financial publication support.