Influence of the volume of ascorbic acid in the synthesis of copper nanoparticles mediated by chemical pathway and its stability over time

In the present investigation, the effect of ascorbic acid volume in the synthesis of copper nanoparticles (Cu NPs) mediated by chemical route and their stability over time was evaluated. For the synthesis, copper sulfate pentahydrate CuSO4 (5H2O) was used as a precursor agent and ascorbic acid (AA) as a reducing agent. Cu NPs was characterized by the following techniques: UV-Visible spectrophotometry to evaluate structural changes that are evidenced in the absorbance peak and atomic absorption spectrophotometry to define nanoparticulate concentrations material in the precipitated and supernatant phases generated. On the methodology it was possible to observe a controlled formation based on the increase in the volume of ascorbic acid in the presence of sodium hydroxide, noticing a production of Cu nanostructures with a tendency to oxidation over time. The UV-visible results showed characteristic surface plasmon resonance peaks of metallic copper for the colloid containing 1.2 mL of A.A; as well as a specific copper concentration of 0.14 ppm in the supernatant and 1519.1 ppm in the precipitate. It is also evidenced that the solution exhibits a rapid reaction on exposure to air by shifting the absorbance peak to 386 nm. In addition, it does not present notable photosensitivity with respect to exposure to sunlight

Ecological and sustainable synthesis of silver nanoparticles from alcoholic extract of Eucalyptus globulus: evaluation of alcoholic solvent influence (70 and 96 )

The present study provides an ecological and sustainable methodology for obtaining nanostructured material from Eucalyptus globulus leaf extract, as a potential value-added alternative and a contribution to circular economy. Silver nanoparticles (NP Ag) were synthesized, through the reducing action of the alcoholic extracts of eucalyptus on the precursor silver nitrate (AgNO3) evaluating the influence of alcoholic solvent (70 ° and 96 °) and pH in the synthesis. The silver colloids obtained were evaluated by UV-vis spectrophotometry, which shows the formation of nanoparticles through the plasmon resonance peak; showing that for pH values 9.9 and 10 with alcohol extract of 70 ° and 96 ° respectively, silver nanoparticles with plasmon resonance peaks at 410 nm and 412.5 nm are obtained. While for pH values 3.86, 11.8 (96°) and 4.7, 8.2 (70°) nanoparticles with higher polydispersity and in a lower proportion are obtained. The results suggest that the alcoholic extracts of eucalyptus can act as reducing agents and that the optimum pH value for the synthesis of silver nanoparticles corresponds to 10

Reuse of organic waste from Eucalyptus globulus extract with high reducing potential in the green synthesis of silver nanoparticles

The research provides a new and sustainable methodology for the synthesis of silver nanoparticles, using Eucalyptus globulus extract, this due to the fact that it presents metabolites capable of acting as a reducing potential of our silver nitrate precursor, and thus obtaining nanostructured material. This is also associated with the reuse of this type of organic material, which currently abounds as waste in the Peruvian highlands. In the specific case of this research, the effect on the stability over time of the biosynthesized silver nanoparticles was evaluated by varying the pH, with values of 4.82, 8.05 and 10.15. It was observed that as the pH increases the production of nanoparticles is higher, having a saturation threshold close to pH 8. It was also found that for alkaline pH close to 10 a more complete reaction of the reducing agent occurs, but with a high dispersion

Incorporation of biosynthesized silver nanoparticles in active biodegradable films of potato starch

En este trabajo se presenta el estudio del efecto de la incorporación de nanopartículas de plata biosintetizadas sobre las propiedades de películas biodegradables fabricadas a partir de almidón de papa y comprobar su potencial para ser usado como material activo. Las nanopartículas de plata fueron fabricadas mediante ruta verde a partir de residuos de uva y fueron añadidas en el proceso de gelatinización de las películas en concentraciones de 3% y 6% v/v. Las nanopartículas de plata fueron caracterizadas mediante espectroscopía UV-Vis y FTIR, mientras que las películas fabricas fueron caracterizadas mediante su densidad y % de contenido de humedad. Las propiedades activas se caracterizaron usando cinética de absorción de agua y biodegradación por enterramiento en suelo. Se confirmó la integración de las nanopartículas de plata en películas biodegradables fabricadas a partir de almidón de papa confirmando los efectos en sus características físicas y propiedades activas en función del porcentaje de AgNp, las cuales pueden ser aprovechadas para la fabricación de materiales activos