Silver antibacterial activity

Martinez-Castanon, G.A., Nino-Martinez, N., Gutierrez, F.M., Mendoza, J.R.M. and Ruiz, F. (2008) Synthesis and antibacterial activity of silver nanoparticles with different sizes. Journal of Nanoparticle Research, 10 (8), 1343-1348. 

Oya, A., Yoshida, S., Abe, Y., Iizuka, T. and Makiyama, N., Antibacterial activated carbon fiber derived from phenolic resin containing silver nitrate, Carbon, 1993, 31(1), 71 73. 

Silver sulfadiazine was first described in 1943 by Wruble (1) and was found to be mildly antiseptic. Fox (2) rediscovered the compound in 1968 in his search for a suitable substance for topical treatment of bums. His philosophy was to combine the oligodynamic effect of the silver ion with the antibacterial activity of sulfadiazine. The compound has been in clinical use in the USA since 1973 and appears to be active against a wide range of micro-organisms (3). The usual application form is a 1% w/w oil-water cream. 

Thirumurugan, G., Shaheedha, S.M., and Dhanaraju, M.D. 2009. In-vitro evaluation of antibacterial activity of silver nanoparticles synthesised by using Phytophthora infestans. International Journal of ChemTech Research, l(3) 714—6. 

Panadek, A., Kvitek, L., Prucek, R., Kolaf, M., Vecefova, R., Pizurova, N., Sharma, V. K., NevScna, T. and Zbonl, R. (2006). Silver colloid nanoparticles Synthesis, characterization, and their antibacterial activity. J. Phys. Chem. B 110 16248-16253. 

AgSD differs from other silver salts in its physical properties it does not react rapidly with chloride or thiol groups or with protein and thus its antibacterial activity is not reduced. It does not become dark on standing or in contact with body tissues and unlike other sulphonamides its activity is not eliminated in the presence of p-aminobenzoic acid (PABA) (2) [40]. 

Organic mercurials mercury, silver, thiomersal, phenylmercuric acetate Broad spectrum of antibacterial activity Low capacity to organic matter, ionic and some non-ionic surfactants toxicicity Eye drops contact lens solutions... 

Xiu ZM, Zhang QB, Puppala HL, Colvin VL, Alvarez PJ (2012) Negligible particle-specific antibacterial activity of silver nanoparticles. Nano Lett 12(8) 4271M275... 

PP/silver nanocomposite fibres were prepared with the aim of achieving permanent antibacterial activity in a common synthetic textile. The fibres were melt-spun by coextmsion of PP and PP/silver masteibatches using general conjugate spinning. Masteibatches were made up of a mixture of PP chips and nano-sized silver powder. The antibacterial efficacy of spun fibres was high when the masteibatch was used as the sheath rather than the core. The antibacterial activity of nano-silver in fibres was evaluated after a certain contact time and calculated by percent reduction of two types of bacteria. Staphylococcus aureus and Klebsiela pneumoniae. DSC and wide-angle X-ray diffraction were used for analysis of stractuie, thermal properties and crystallisation behaviour of the spun fibres. SEM was carried out in order to observe particle distribution on the nanocomposite fibres. 17 refs. (2nd International Conference on Polymer Fibres, Manchester, UK, July 2002)... 

The antibacterial behaviour of cold sprayed HAp-Ag (silver-doped hydrox-yapatite)/PEEK composite coatings were investigated against Escherichia coli (DH5a) by Sanpo et al. (2009). The antibacterial activity was found to increase with increasing concentration of HAp-Ag nanoparticles. The precursor nanocomposite powders were deposited using rather mild cold spraying parameters (11-12 bars, preheated air temperature between 150 and 160 °C). 

A number of carbene complexes have also been demonstrated to exhibit good antibacterial activity.Notably, silver nitrate has been widely used to prevent the infection of burn wounds. The key feature of dmg activity is the... 

Silver possesses antibacterial activity against gram-positive and gram-n ative microorganisms. Silver protein, mild, is occasionally used in tlie treatment of eye infections. Slver nitrate is occasionally used to prevent gonorrheal ophthalmia neonatomm (gonorrhea infection of tlie newborn s ey ). Ophthalmic tetracycline and erythromycin have largely replaced tlie use of silver nitrate in newborns. 

MIC values confirmed the noticeable antibacterial activity of the fabricated polymer by the response of Enterococcus faecalis. Streptococcus pneumoniae and Staphylococcus aureus. The antimicrobial properties of pure nanofibrillated cellulose (NFC) coated with Ppy-silver composite (Scheme 7.4) films were tested on yeast Candida albicans), a Gram-negative bacterium Salmonella serovar Infantis) and a Gram-positive bacteria Listeria monocytogenes and Staphylococcus aureus) (Table 7.3) [60]. 

It has been reported that silver ion-exchanged zeolites exhibit antibacterial activity [32]. The mechanism of antibacterial action of the zeolite is initiated when moisture or liquid film comes into contact with the ion exchange material and silver ions are exchanged with sodium (Na) or other cations from the environment [33]. The released silver ions attach to the bacteria by forming chelate complexes with deoxyribonucleic acid, which blocks the transport processes in the cell [34]. The use of zeolite as a filler in polymeric materials has been reported in the literature and it has been proved that they enhance the antibacterial activity of the polymer [35]. Furthermore, the effect of zeolite content on the physical and thermal properties of the polymer was also examined [35] increasing the silver/zeolite ratio in the polymer led to an increased antimicrobial activity (due to the higher silver ion concentration), but depending upon the application the zeolite content may influence physical, thermal and/or chemical properties of the polymeric material. 

However, clinical studies have proved that the antibacterial activity of silver-sulfadiazine impregnated catheters decreased rapidly. 

Antibacterial Activity of Polyaniline/Polyvinyl Alcohol/Silver... 

In this study [46], poljwinyl alcohol (PVA)/polyaniline (PANI)/silver nanocomposites were tested for antibacterial activity against Escherichia coli and Staphylococcus aureus. The nanocomposite samples resulted in ZOI with diameters of the 7, 8,12, 9 and 8 mm and 10,12,15,9 and 8 mm against Escherichia coli and Staphylococcus aureus, respectively. It was observed that the PVA/PANI composite, which was used as a control matrix, exhibited no antibacterial activity when compared with PVA/ PANI/silver nanocomposites. 

Antimicrobial CS-silver nanocomposites are also potentially new and exciting antimicrobial agents against varions pathogens. CS-silver nanocomposites, either in the form of silver NP or as ionic dendritic strnctures (Ag ) can be easily synthesised by a simple and environmentally friendly in situ chemical reduction process and could be efficient antimicrobial agents. Below specific critical concentrations, the collective action of silver NP and Ag " ions facilitate enhanced and synergistic antibacterial activity. 

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