SILVER NANOPARTICLES SYNTHESIS. BIOREDUCTION WITH GALLIC ACID AND EXTRACTS FROM CYPERUS ROTUNDUS L

Silver ions chemical reduced in AgNPs proved to be inappropriate for medical applications; some of the reagents have a high level of toxicity. Green synthesis removes these barriers by using the plant extracts rich in phytocomplexes with high bioreduction capacity. The investigations are focusing on therapeutic effects and lesser related to the bioreduction mechanisms- phytochemical composition characterized by global parameters: total phenol content (TPC), total flavonoid content (TFC), total antioxidant capacity (TAC). TPC and TFC are measured by comparison with the gallic acid and a flavonoid (ex quercetin), respectively. Understanding their bioreduction mechanisms is useful to have a comparison criterion for each plant extract, such as TPC/TFC-ratio. In this respect, are studied the bioreduction activity for gallic acid using Pourbaix diagram, microspeciation, surface plasmon resonance, and Mie scattering, zeta potential, kinetics parameters derived from UV-vis spectroscopy and DLS. At the end are presented the kinetics parameters for the extracts from Cyperus rotundus L., a plant with a high impact in phytotherapy. In introduction are summarized several keypoints, support for the understanding of the bioreduction kinetics.