Investigation of optical properties and antibacterial activity of chitosan copper nanoparticle composites
T. Fahmy, Afaf Sarhan
Abstract
Chitosan (Cs) doped with different proportion of copper nanoparticles (CuNPs) has been prepared using the casting method in an oven at T = 333 K. The optical properties of Cs/CuNPs have been investigated using different techniques such as, UV-Vis and FTIR spectroscopy. Many optical parameters such as optical band gap energy, oscillation energy, dispersion energy and lattice dielectric constant of all samples have been estimated. FTIR spectra of Cs and Cs/CuNPs have been investigated and the results revealed that, a broadness of OH groups in Cs/CuNPs has been observed. XRD measurements showed that, average of the particle size is approximately ~ 8.11 nm. Measurements of swelling showed that, the maximum swelling decreases linearly with increasing concentration of copper nanoparticles. The antibacterial activity of chitosan and Cs/CuNPs samples has been investigated against gram-positive (Staphylococcus aureus) and gram-negative (Escherichia colii). The results revealed that, irradiated samples with UV-irradiation exhibited a greater activity in comparison to the non-irradiated samples.