Silver antimicrobial applications

Zain, N.M., Stapley, A.G.E., Shama, G., 2014. Green synthesis of silver and copper nanoparticles using ascorbic acid and chitosan for antimicrobial applications. Carbohydr. Polym. 112, 195-1202. 

Chalal Sarnia, Haddadine Nabila, Bouslah Naima, and Benaboura Ahmed. Preparation of poly (acrylic acid)/silver nanocomposite by simultaneous polymerization-reduction approach for antimicrobial application. J. Polym. Res. 19 no. 12 (2012) 1-8. 

Despite the pronounced antimicrobial effect, silver ions have only limited usefulness as an antimiaobial agent in applications such as medicine, clothing, and household products. This is due to their rapid binding to or inactivating by components of the medium. This limitation can be overcome by using as an antimicrobial agent, silver nanoparticles, which continuously release Ag ions in sufficient concentration [16]. 

Silver nanoparticles synthesized by a cost-effective three-stage electrochemical technique have demonstrated great promise as antimicrobial agents. Nanosilver was less effective against E. coli, S. aureus, B. subtilis and P. phoeniceum compared to silver ions. However silver nanoparticles have prolonged bactericidal effect as a result of continuous release of Ag ions in sufficient concentration and thus nanoparticles can be more suitable in some bactericidal applications. The synthesized silver nanoparticles added to water paints or cotton fabrics have demonstrated a pronounced antibacterial/antifungal effect, despite the fact that they tend to agglomerate into clusters up to 200 nm. 

Silver(I) carbene complexes are characterised by a broad range of different structures [314]. Hence, it is not surprising that Melaiye et al. [488] found an infinite chain structure as the underlying motif in a water soluble silver(l) pincer carbene complex (see Figure 3.168). Water solubility was achieved by the introduction of pendant hydroxyalkyl wingtip groups. Water solubility of the silver(l) pincer carbene is desirable when the compound is used as an antimicrobial agent in medical applications [489]. 

The use of 1% silver nitrate eye-drops in prophylaxis of ophthalmia neonatorum has been periodically reviewed and compared with other prophylactic measures. There seems to be no case in which permanent damage to the eye was actually proven to have been caused by a single application of a correctly used 1 % silver nitrate solution (23). However, silver nitrate has largely been replaced by antimicrobial drugs. 

Antimicrobial properties of silver have been known and utilized for centuries. It is well established that only silver ions are antimicro-bially active, while elemental silver is not. Many biomedical devices have been coated with silver and/or silver compounds for antimicrobial purposes. The applications of surfaces treated with silver or its compounds include devices such as topical wound dressings, urinary catheters, endotracheal tubes, cardiac valves, etc.72 Electroless deposition of silver or its compounds can quite successfully be used for coating of biomedical devices. 

Silver is relatively non-hazardous and has FDA approvals for food contact applications (118). The main disadvantage of silver is that in most applications its cost will be double or triple that of an equivalent organic antimicrobial. 

MILLIKEN S SILVER-BASED ANTIMICROBIAL RECEIVES EPA APPROVAL FOR HVAC APPLICATIONS... 

These biopolymers can be used for the immobilization of metal ions not only with the final objective of metal recovery (and subsequent valorization by desorption or chemical/thermal destmction of the polymer matrix) but also for elaborating new materials or designing new applications. Depending on the metal immobilized on the biopolymer, it is possible to design new sorbents (immobilization of iron on alginate [119], of molybdate on chitosan [59], for As(V) removal, of silver on chitosan for pesticide removal [120]), supports for affinity chromatography [121], antimicrobial material [122], drug release material [123], neutron capture therapy [124], and photoluminescent materials [125]. These are only a few... 

The nurse is discussing the application of silver nitrate, an antimicrobial agent, to a client with a partial-thickness burn to the left leg. Which information should the nurse teach the client when discussing how to apply this medication after discharge ... 

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. 

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. 

Furthermore, composite films of nanofibrillated cellulose (NFC)/Ppy and NFC/ PPy-silver NP are a suitable candidate for use in biomedical applications. Due to the electrical conductivity and strong antimicrobial activity of these silver composites, they can be used in various applications, in particular, biomedical treatments and diagnostics. 

The synthesis of functional polymers containing silver NP is environmentally friendly, experimentally simple and extremely quick. It opens up new possibilities for the development of antimicrobial coatings with medical and sanitation applications. 

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