Silver antimicrobial efficacy

A CVC coated with an antiseptic combination, silver chloride and benzalkonium chloride(BKC), in a polymer(PU) matrix was developed. The antimicrobial efficacy and the ability to prevent surface colonisation. 

Rhodanine by-products have been used as antiviral, antibacterial, antihistaminic and anticorrosion agents [34, 35]. Additionally, they have also been used to identify metal ions as the rhodanine molecule has metal-binding functional groups, such as thioamide and amide [36, 37]. It is thought that the improved antimicrobial efficacy of the silver/polyrhodanine nanofibres is due to the joint antimicrobial activity of silver and polyrhodanine nanofibres. Silver NP-embedded polyrhodanine nanofibres can be prepared via chemical oxidation polymerisation. 

On the other hand, layer-by-layer (LbL) assemblies have demonstrated their importance in a variety of biomedical applications. Polyelectrolyte multilayers have also been prepared using silver nitrate and/or cetrimide as the antimicrobial agents [44]. The substitution of cetrimide for silver dramatically enhances the antimicrobial efficacy of these films, as evidenced by the ZOI data. Furthermore, cetrimide is not susceptible to reduction as is ionic silver, resulting in highly transparent, colourless films. 

K.M. Hindi, A.J. Ditto, M.J. Panzner, D.A. Medvetz, D.S. Han, C.E. Hovis, J.K. Hilliard, J.B. Taylor, Y.H. Yun, C.L. Cannon, The antimicrobial efficacy of sustained release silver-carbene complex-loaded 1-tyrosine polyphosphate nanoparticles characterization, in vitro and in vivo studies, Biomaterials 30 (2009) 3771-3779. 

Damm, C. Milnstedt, H. Rosch, A. The antimicrobial efficacy of polyamide 6/silver-nano- and microcomposites . Materials Chemistry and Physics, 2008,108(1), 61-66. 

The ZOI test, also widely known as the Kirby-Bauer disk diffusion test, is a fast in vitro but semiquantitative test [169], The original purpose of this test was to replace the MIC test for small molecule antibiotic efficacy [169], Soon, this method was adopted and modified to evaluate antimicrobial efficacy of silver and polymeric devices with eluting antimicrobial agents [170], Conunonly used eluting antimicrobial agents are zinc salt/particles [171-173], silver salt/particles [173-177], and chlorhexi-dine [178,179], These antimicrobial agents can be compounded/blended into polyurethanes or coated/adsorbed on polyurethanes. 

Damm C, Milnstedt H, Rdsch A. The antimicrobial efficacy of polyamide 6/silver-nano-and microcomposites. Mater Chem Phys 2008 108 61-6. http //dx.doi.org/10.1016/ j.matchemphys.2007.09.002. 

The library of silver-NHC compounds has been greatly expanded due to the contributions of Tacke and coworkers (13a-21) [13-17] and Roland et al. (22a-25b) [18]. Compounds 13a-21 (Figure 6.1), all bearing the acetate ligand, were evaluated for their antimicrobial efficacy against S. aureus and . coli using a qualitative Kirby-Bauer disk-diffusion method. The imidazolium salt precursors, silver acetate, and the vehicle (dimethylsulfoxide) served as controls. The results of the tests were mixed, with a number of compounds having a weak... 

M.H. Cavanagh, R.E. Burrell, and P.L. Nadworny, Evaluating antimicrobial efficacy of new commercially available silver dressings. Inter. Wound., 7 (5), 394-405,2010. 

Raad, I., Hachem, R., Zermeno, A., Dumo, M. and Bodey, G. P., 1996. In vitro antimicrobial efficacy of silver iontophoretic catheter. Biomaterials 17, 1055-1059. 

Copper at low concentrations below 2 mg Cu" /kg serve as a co-factor for metalloproteinase and enzymes, hence, it has potent apphcation of antimicrobial properties. Environmental Protection Agency (EPA) of the United States approved the registration of copper based alloys on the claim that they reduce microbial infections and confirmed the antimicrobial efficacy ((http // www.epa.gov/pesticides/factsheets/copper-alloy-products.htm). Nano-sized ZnO particles have biocidal activity and several advantages over the silver nanoparticles. They have low cost, white appearance, high versatility, and doping ability with several inorganic carriers and UV blocking property. 

Elemental and ionic silver have long been known to hold antimicrobial properties, and within the last decade it has been discovered that nanoparticulate silver likewise can kill or inactivate a wide range of bacteria, viruses, fungi, and other microscopic organisms. It continues to be a matter of debate whether silver nanoparticles (AgNPs) differ from free silver ions in their mechanism of action or antimicrobial efficacy (Seil and Webster 2012 Sweet and Singleton 2011 Duncan 2011a). 

Figure 15.1 NHC-silver(i) complexes synthesized by the Youngs group tested for in vitro and in vivo antimicrobial efficacy.

The pnrpose of onr stndy was (a) to quantitatively estimate antimicrobial effect of silver nanoparticles comparing it with that of silver ions and (b) to study the efficacy of nanosilver as an antimicrobial agent against a range of microbes on the surface of paints and 100% cotton fabrics. 

To compare the bactericidal efficacy of silver nanoparticles and silver ions, the minimum inhibitory concentration (MIC) assays were conducted for gram-negative bacterium E. coli, gram-positive bacteria S. aureus and B. subtilis and fungus P. phoeniceum. The data on MICs are summarized in Table 18.1. The results demonstrated that the antimicrobial activity of silver ions was superior to that of silver nanoparticles against all microbes tested. 

Evidence of Efficacy of 10 PPM Silver Composition as a Broad Spectrum Antimicrobial... 

The purpose of this example is to demonstrate the efficacy of a silver composition of the present invention against the bacteria that cause tuberculosis. This example describes the procedures for evaluation of the present invention for tuberculocidal efficacy. The methodology is based on the Tuberculocidal Activity Test Method as accepted by the EPAon Dec. 11, 1985. [Refer to United States Environmental Protection Agency, 1986. Office of Pesticides and Toxic Substances. Data Call-In Notice for Tubercuolocidal Effectiveness Data for All Antimicrobial Pesticides with Tuberculocidal Claims. (Received Jun. 13, 1986). 

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