Synthesis and Characterizations of Silver Colloid Nanoparticles Stabilized by Dextran

This study aims to investigate the influence of different concentration of silver nanoparticles in Dextran (Dx) suspension. The silver nanoparticles (AgNPs) were prepared by chemical reduction method using reduction agents, Dextran (Dx) under moderate temperature at different concentration. Three different sample solutions were prepared viz., 0.4, g0.8 and 1.2% (w/v) Dx at a constant temperature (80C). Silver nitrate (AgNO3) was taken as the metal precursor while Dx was used as the solid support and polymeric stabilizer. The formation of nano silver was identified by the color change from white precipitate to yellowish-brown color. Formation of Ag-NPs was determined by UV–Vis spectroscopy where surface plasmon absorption maxima can be observed at 412–437 nm from the UV–Vis spectrum. The synthesized nanoparticles were also characterized by X-ray diffraction (XRD). The peaks in the XRD pattern confirmed that the AgNPs possessed a face-centered cubic and peaks of contaminated crystalline phases were unable to be located. The Fourier transform infrared (FT-IR) spectrum suggested the complexation present between Dx and AgNPs. Scanning Electron Microscopy (SEM) with EDX and Atomic Force Microscopy (AFM) was applied to characterize the morphology, particle size distribution of the AgNPs. The average particle size of the stabilized samples ranged from 10-40 nm. It was demonstrated that this convenient method is versatile to produce silver nanoparticles with controlled size and shape.