Bactericidal and Fungicidal Action of Copper Nanoparticles on Leather Surface

Although tanning makes the collagen matrix resilient against microbial attack, the chemicals used in the finishing process are susceptible to microbes. Hence, it is imperative to develop a finishing process with inherent antimicrobial properties. Leathers with antimicrobial properties evoke a considerable array of interest in consumers. The present study aims to enhance the antimicrobial properties of the leather using copper nanoparticles in the finishing and retanning process. Copper nanoparticles have been synthesized by chemical reduction using copper sulphate pentahydrate as the precursor with dialdehyde starch and gallic acid. The prepared nanoparticles have been characterized using UV-Visible spectrometry, dynamic light scattering, scanning electron microscopy, transmission electron microscopy, and X-ray  diffraction techniques. The prepared nanoparticles have been used in both retanning and finishing processes. The experimental leather retanned using copper nanoparticles possess good mechanical strength properties and color index value compare to the control. Nanoparticles are effective against both gram negative and positive bacterial organisms. The nanoparticles also inhibit the growth of common fungus, which can colonize on leather. Thus, the current study paves the way for a novel solution that is an alternative to biocides and antimicrobial chemicals and is more effective in inhibiting microbial growth.