4.6.1. Ultraviolet–Visible Absorption Spectroscopy (UV-Vis)

UV–vis spectroscopy was used to characterize the optical absorption properties of copper nanoparticles. The absorption spectra of samples were recorded in the wavelength range of 250 to 650 nm using a UV-6800 UV\VIS spectrophotometer (JENWAY, Bruker, Ettlingen, Germany), at the Medical Biophysics Department, Medical Research Institute, Alexandria University. CuNPs suspension (1 mL) was placed in a quartz cuvette to record its wavelength absorption.