Figure 1 presents the UV–Vis spectrum of the colloidal
silver particles. The formation of AgNP was
confirmed by the presence of the absorption plasmon
peak around 390 nm (Khlebtsov 2008). This peak is
characteristic of the collective oscillation of the
conducting electrons in the nanoparticles surfaces in
the presence of a light wave field (Khlebtsov 2008).
The intensity of the peak is proportional to the AgNP
concentration; the full width at half maximum is
proportional to the size distribution (Medina-Ramirez
et al. 2009).