Biofunctionalization of silver/silver chloride nanoparticles and their physicochemical and biological characterization
Jarvy Francisco Cruz-Hernández1, Maricela Villanueva-Ibáñez1, Blanca Estela Jaramillo-Loranca1, Yuridia Mercado-Flores2, Gilgamesh Luis-Raya3, Jesús Garcia-Serrano4
1 Laboratory of Nanotechnology, Biological Systems and Industrial Applications, Polytechnic University of Pachuca (UPP), Zempoala, Hidalgo, Mexico.
2 Laboratory of Integral Use of Biotic Resources, UPP, Zempoala, Hidalgo, Mexico.
3 Laboratory of Energy Sources and Crystalline Solids Applied in Optoelectronic Devices, UPP, Zempoala, Hidalgo, Mexico.
4 Área Académica de Ciencias de la Tierra y Materiales, Universidad Autónoma del Estado de Hidalgo, Mineral de la Reforma, Hidalgo, México
In recent years, research has increased to implement nanomaterials in different areas, especially health. However, the methods used to obtain nanoparticles involve sophisticated equipment that increases production costs and chemicals that can be toxic. The alternative for nanoparticle synthesis is the biological method because it reduces these disadvantages and provides biofunctionalization. In this sense, silver and silver chloride nanoparticles (AgNPs and AgClNPs) have shown antibacterial activity against human pathogens. Therefore, in this project, silver-based nanomaterials were synthesized and characterized using the aqueous extract of Coffea arabica green beans. By UV-Vis spectroscopy, bands at 361 and 430nm corresponding to AgClNPs and AgNPs, respectively, were observed. X-ray diffraction analysis allowed the identification of the cubic structure centered on the faces at the 2 theta angles of 38.16°, 44.38° and 64.66° corresponding to the Bragg refraction of (111), (200) and (220), respectively, characteristic of AgNPs and at 46.31°, 54.92° and 57.55° assigned to the (220), (311) and (222) planes of the AgClNPs. In dynamic light scattering analysis, particle sizes greater than 100 nm were determined; however, using TEM, agglomerates of particles with sizes of 20-50 nm surrounded by organic material from the C. arabica extract were observed. The nanoparticles showed antioxidant activity against the DPPH radical and antibacterial activity against E. coli and B. subtilis, regarding the minimum bactericidal concentration of 250ppm for both strains.