Green synthesis of silver nanoparticles and modification with paper pulp for antimicrobial applications
Luis A. Deschamps, Gesira De Avila, and Adriana P. Herrera
Assistant Professor at the Chemical Engineering Program of the University of Cartagena, Colombia. I Finished my PhD in Chemical Engineering from the University of Puerto Rico (2009) and I worked as a Postdoc with the Institute of Functional Nanomaterials at UPR (2009-2011). I have a strong experience in chemical synthesis of nanoparticles, characterization of nanomaterials, colloid interface science, materials science, and bio-interfaces. My research initiatives are focused on the engineering design of smart nanomaterials for bio-engineering, biomedical, environmental, and energy applications.
In this work, we describe the synthesis of eco-friendly silver nanoparticles from a silver nitrate solution prepared at concentrations of 1, 10, and 100 mM. Moreover, we used a natural leaf extract from coriander (Coriandrumsativum), which allowed the formation of nanoparticles without the production of traces of toxic pollutants. The physical-chemical properties of the synthesized nanoparticles were determined by using spectroscopic techniques such as UV-Vis, from which we observed absorption at the wavelength ranging from 430 to 455 nm-1, which it is characteristic of the surface plasmon resonance of the silver nanoparticles. Additionally, we used the dynamic light scattering to determine the hydrodynamic size of the synthesized nanoparticles, obtaining an average size of 74±25 nm. To determine the susceptibility of these nanoparticles to be used as antimicrobial agents in the production of bio-active food packages, the synthesized silver nanoparticles were dispersed in samples of paper pulp, which are mainly formed by cellulose and can be used as a hydrophilic support of the nanoparticles. The cellulosic materials modified with the nanoparticles were put in contact with the E. coli bacteria during 24 and 48 h, from which we observed the inhibition of the bacteria growth by following the standard procedure described for Bauer-Kirby (1966), which indicated the potential opportunity for the application of these nanomaterials as antimicrobial agents
Keywords: Silver nanoparticles, natural solvent, cellulose, antimicrobial, E. Coli.