Swelling Studies of the Gel

The exact mechanism of silver nanoparticles interact with bacteria is still unexplored. In contact with water and dissolved oxygen silver nanoparticles release small amount of silver ions according to the following equation [Kacarevic et al., 2007 Bajpai et al., 2013] 

It was interpreted that the silver [I] ions, released from silver nanoparticles offer a physical barrier to its diffusion of the bacterial cells might be the reason for killing bacteria. One of the proposed mechanisms is that ionic silver strongly interact with thiol groups of vital enzymes and inactivates them [Jay and Tanju, 2002 Yoshinobu et al, 2003]. 

6 Identification of Silver Particles in the Hydrogel/Metal Nanocomposite 

The crystallinity of hydrogel/silver nanocomposite could be established by diffraction studies. The formation of silver nanoparticle confirm by International Centre of Diffraction Data, ICDD, library of silver. The diffraction peaks for hydrogel/silver nanocomposites found at 26 value of 38.1°, 44.26°, 64.50°, and 77.42° are attributed due to (111], (200], (220], and (311] planes of FCC, respectively (Bajpai et al., 2013 Daniel et al., 1996 Murali Mohan et al., 2010]. Pure hydrogel failed to show any peak in the XRD indicating its amorphous nature. In order to check whether the silver nanoparticles were oxidized to silver oxide, the XRD pattern of composite after storing it for three months was compared with original one. If it has the same pattern as that of fresh hydrogel/silver nanocomposite, this indicates its stability at ambient condition. 

The interaction between the hydrogel and silver particles can be determined by FTIR spectral studies. For hydrogels containing 

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