In recent years, the development of efficient Green Chemistry methods
for the synthesis of metallic nanoparticles has become a major focus for
researchers as well as the characterization of the materials produced. This work
aimed at the study and production of silver nanoparticles synthesized by
reduction of plant extract without the addition of any other constituent for its
stabilization in the reaction medium. In this study the methods of synthesis
mediated by the reduction of silver ions by ascorbic acid and other biomolecules
present in the vegetal extract of camu-camu fruit (Myrciaria dubia) were
analyzed, seeking their reproducibility regarding the synthesis conditions used.
Colloidal silver nanoparticle dispersions were obtained by varying the synthesis
conditions such as reaction time, reagent concentration and temperature, and
the progress of the reaction was monitored by the results of UV-visible
spectroscopy. The study showed that the extract of camu-camu as a reducing
agent is feasible for the reduction of silver ions for the synthesis of
nanoparticles in aqueous medium, so that at different concentrations and
temperatures the reaction is directly influenced, and the extract, in high
concentrations, can decrease the reaction kinetics, causing a decrease in the
rate of particle formation. Additionally there is a reduction in the maximum
absorbance detected progressively when the temperature of the reaction
medium rises, making its extract reduction capacity smaller due to degradation
of the biomolecules.
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