3.1.1. UV-Visible Spectroscopy

Among the primary spectroscopy techniques utilized for the characterization of nanoparticles, this absorption spectroscopy technique is used to evaluate the light-matter interactions and has profound relevance for the determination of the optical properties of nanoparticles including key characteristics such as shape, size, and stability [35,36]. The UV-visible absorption study of the six different ZnNPs illustrated distinct and sharp absorption peaks to vary between wavelengths ranging from 210 to 350 nm (Figure 2). All the reducing and capping agents derived ZnNPs exhibited a single and sharp peak at 210 or around 210 to 220 nm except Starch (RA) (dual distinct peaks at 212 and 350 nm) and Starch (CA) (triple peaks at 212, 260, and 330 nm) derived ZnNPs.
