**8. Nanoparticle-Based Green Synthesis-Regulated Parameters: Clues to Enhance Their Activity**

Different parameters should be used to optimize synthesis and obtain high efficiency, stabilized, and applicable NPs. These parameters include the type of synthesis method, temperature, pH, time of exposure, concentration of reductants and stabilizing agents, concentration of bulk materials, type of natural sources, illumination, and microorganism growth phase (Figure 6).

**Figure 6.** Nanoparticle-based, green synthesis-regulated parameters including (**1**) growth phase of organisms, (**2**) temperature, (**3**) concentrations of reductants and bulk materials, (**4**) protocols of green synthesis, (**5**) time of exposure, (**6**) type of natural sources, (**7**) illumination conditions and (**8**) pH.
