Ecofriendly Synthesis of Silver-Carboxy Methyl Cellulose Nanocomposites and Their Antibacterial Activity.

A straightforward and environmentally benign method for the synthesis of silver nanoparticles (AgNPs) is reported in this paper. A sustainable and nontoxic polysaccharide carboxy methyl cellulose (CMC) was used as both reducing agent and stabilizer in the process of synthesizing AgNPs. By varying the precursor concentration, solution pH value, reaction temperature and duration, the highly stable and smaller sized AgNPs with narrow size distribution were obtained. The as-synthesized AgNPs were characterized using UV-Vis absorption spectroscopy, high resolution transmission electron microscopy, X-ray diffraction and zeta potential and size analyzer. Measurements of optical spectra showed that the surface plasmon resonance was localized around 404 nm. The TEM images showed that the particles are well dispersed and spherical in shape with an average particle diameter of 11.64 ± 2.32 nm which is less than the value (13.12 ± 1.54 nm) measured by dynamic light scattering. The zeta potential value of AgNPs was measured to be − 62.8 mV which indicated that CMC coated on the surface of as-synthesized AgNPs resulting in the negatively charged surface and the stable in nature. The prepared silver nanoparticles are effective in inhibiting the growth of both gram positive Staphylococcus aureus and gram negative Escherichia coli. [ABSTRACT FROM AUTHOR]