%0 Journal Article %T Development and Characterization of Semi-IPN Silver Nanocomposite Hydrogels for Antibacterial Applications %A A. Chandra Babu %A M. N. Prabhakar %A A. Suresh Babu %A B. Mallikarjuna %A M. C. S. Subha %A K. Chowdoji Rao %J International Journal of Carbohydrate Chemistry %D 2013 %I Hindawi Publishing Corporation %R 10.1155/2013/243695 %X Sodium carboxymethyl cellulose/poly(acrylamide-co-2-acrylamido-2-methylpropane sulfonic acid) semi-interpenetrating polymer network (semi-IPN) hydrogels were prepared by using free radical polymerization technique. Silver nanoparticles were formed by reduction of silver nitrate in semi-IPN hydrogels with sodium borohydrate at room temperature. UV-visible spectroscopy, thermogravimetrical analysis, X-ray diffractometry, scanning electron microscopy, and transmission electron microscopy techniques were used to characterize the formation of silver nanoparticles in hydrogels. SEM images indicated clearly the formation of group of silver nanoparticles with size range of 10每20ˋnm. The sizes of silver nanoparticles were also supported by transmission electron microscopy results. The semi-IPN silver nanocomposite hydrogels reported here might be a potentially smart material in the range of applications of antibacterial activity. 1. Introduction Nanocomposite polymer hydrogels may be defined as crosslinked three-dimensional polymer networks swollen with water or biological fluids in the presence of nanoparticles. The design and development of such materials containing metallic nanoparticles have scientific and technological research interests in recent years due to their unique and versatile properties [1每5]. These properties lead to potential applications in the field of numerous physical, biological, biomedical, and pharmaceutical sectors [6每13] as well as optical, electrical, chemical, and data storage [14每18]. These properties are known for silver in the form of ions, colloidal particles, nanoparticles, metallic silver, and silver compounds, and many works study their use to inhibit the proliferation of microorganisms for medical [19每21], food packaging [22, 23], and water treatment [24, 25] applications. Generally silver ions, as heavy metals, lead to the inactivation of proteins reacting with thiol groups (每SH) on the membrane of bacteria causing the microbial cell death [26每28]. The biological activity of silver, especially the antibacterial property, is size dependent [29]. Thus silver nanoparticles should be small enough to pass through the cell membrane. Silver ions kill microorganisms instantly by blocking their respiratory enzyme systems, while having no negative effect on human cells. Although nanocomposites containing metal NPs have elegant features, the homogeneous dispersion of metal NPs is not easy using a simple process because of their high surface free energy, which may cause agglomeration. Therefore, preparation of such nanocomposites with %U http://www.hindawi.com/journals/ijcc/2013/243695/