%0 Journal Article %T Comparative Study on the Synergistic Action of Differentially Synthesized Silver Nanoparticles with ¦Â-Cephem Antibiotics and Chloramphenicol %A Neethu Hari %A Tincy K. Thomas %A A. Jayakumaran Nair %J Journal of Nanoscience %D 2014 %R 10.1155/2014/201482 %X Synergistic activity of cephem antibiotics with silver nanoparticles (Ag NPs) was investigated. Silver nanoparticles were synthesized through biological and chemical method. The combined action of ¦Â-lactam cephem antibiotics with both green and chemically synthesized silver nanoparticles enhances the antibacterial activity against wide range of antibiotic resistant pathogens and making them applicable to medical devices and microbial control systems. Synergistic activity of chloramphenicol with silver nanoparticles was also studied. 1. Introduction Beta-lactam antibiotics (penams and cephems) are the largest group of antibiotics widely used in clinical medicine because of their high antibacterial activity [1]. ¦Â-Lactam groups of compounds are the most successful example of natural product application and chemotherapy [2]. All the natural and semisynthetic derivatives of ¦Â-lactam have their own properties and wide range of applications. Cephem derivatives are one of the new groups of ¦Â-lactam antibiotics with cephem ring and they show potent activity against different types of bacteria. Cephem class includes cephalosporins and cephamycins of which more than 22 antibiotics are now in clinical use and the efficacies of these drugs depend on their antibacterial spectra, potencies, and concentrations in tissues. But the empirical therapy and extent use of these agents have caused the development of bacterial resistance by different mechanisms like production of different kinds of ¦Â-lactamases (¦Â-lases), alteration of the antibiotic target site, and prevention of access of the antibiotic to the target by way of altered permeability or forced efflux and this may compromise the potential of ¦Â-lactam antibiotics. In this regard, considerable attention has been given to silver nanoparticles (Ag NPs), which have well-known antimicrobial properties and are used extensively in various medical and general applications and also the antibacterial, antifungal, and antiviral properties of silver ions, silver compounds, and silver nanoparticles have been extensively studied [3]. Moreover, high surface to volume ratio of silver nanoparticles may contribute to their enhanced antimicrobial properties by increasing the contact surface of silver nanoparticles with the microorganisms. Several studies also suggest that silver nanoparticles, which are well known to have broad spectrum antimicrobial activity against bacteria, virus, and eukaryotic microorganisms [4], interact with the cell membrane and some of them will penetrate the bacterial cell wall, thereby causing the death %U http://www.hindawi.com/journals/jns/2014/201482/