As shown in Figure , the hydrodynamic diameter of the suspension containing CuO NPs, determined by the DLS, was 63.41 nm. This value is consistent with studies in the literature (Table ), where a larger cumulative distribution is observed between 40 nm and 70 nm. Particle size is a significant factor, since smaller particles have a larger surface area concerning their volume, contributing to the agglomeration and repulsion effects of NPs. It is important to mention that the average particle size using DLS analysis is affected by several factors, such as percentages of homogeneity (sizes increased with the inhomogeneous distribution of CuO NPs in the solution) and plant metabolites that cover the surface of the NPs, interfering with the size calculation .