Enhancement of multifunctional properties of leather surface decorated with silver nanoparticles (Ag NPs)

The leather is a durable and flexible protein that can be created by tanning animal rawhide and skins. In this work, a simple method was developed for the functionalization of leather surfaces in terms of excellent coloration and protective properties against micro-organisms and UV radiation. The multifunctional leather surface was obtained through in-situ deposition of silver nanoparticles (Ag NPs) onto the leather surface by employing trisodium citrate (TSC). TSC acts as both a reducing and stabilizing agent. The figuration of Ag NPs in the solutions was evaluated by UV/Vis spectra and the morphology of nanoparticles was determined by TEM. The treated leather samples (Leather/Ag NPs) were evaluated by different tools including SEM, EDX, ATR-FTIR, XRD, TGA, as well as silver content. The impact of the Ag NPs on the coloration, UV-protection, and anti-microbial properties of the leather surface was evaluated. Results disclosed that the nanoparticles are mostly in spherical shapes, regularly distributed, and closely anchored onto the leather surface. The particle size distribution of nanoparticles onto the leather surface was in the range of 55 ± 17 and 130 ± 16 nm for leather/Ag NPs (300 ppm) and leather/Ag NPs (1000 ppm) respectively. The leather/Ag NPs samples were revealed good color properties in terms of color homogeneity, strength as well as excellent fastness properties. The leather/Ag NPs samples were exhibited a yellow/brown color. Moreover, the leather/Ag NPs (1000 ppm) sample was exhibited the highest a* value (6.1 ± 0.8) and b* value (27.8 ± 1.9). The leather/Ag NP sample was showed the highest silver content (1849 ± 3 mg/kg) and much higher UPF value (478 ± 3) than the other samples. Furthermore, the leather/Ag NPs samples were exhibited broad-spectrum antimicrobial activity against different micro-organisms. The leather/Ag NPs (1000 ppm) sample was demonstrated excellent antimicrobial properties with 100% bacterial reduction efficiency against both Gram-positive and Gram-negative bacteria and more than 93% fungal reduction efficiency against Candida albicans