Carbon: Science and Technology (Mar 2013)
Antibacterial activity of Nano-Silver capped by β-Cyclodextrin
Abstract
Silver nanoparticles were prepared by chemical reduction method using sodium citrate as reducing agent, followed by capping with various concentrations of β-Cyclodextrin (β-CD) and characterized by various physicchemical characterization techniques. Antibacterial activity of Pseudomonas aeruginosa (Gram-negative) and Staphylococcus aureus (Gram-positive) was determined by Well-Diffusion method. The nano-silver were spherical under Scanning electron microscopy (SEM) and the XRD result shows average diameters of capped particles are smaller than their equivalent uncapped particles. Capped nano silver particles of four different concentrations were demonstrated as superior for photo stability, when exposed to intense ultraviolet (UV-Vis) radiation for 4 hours, as well as significantly higher antibacterial activity. The influence of β-CD concentration (5 mM, 10 mM and 15 mM) was seems to be delay in bacterial growth, showing that a Trojan horse mechanism may be owing to occur bacterial affinity, thereby improving silver ion absorption.