Silver nanoparticles 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. 

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. 

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

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 comparison of the antibacterial activity of normal chitosan, nanochitosan, and silver-loaded nanochitosan applied on woven polyester fabrics showed that the nanoparticle form of chitosan imparted much enhanced antibacterial activity, as indicated by a reduction in minimum inhibitory concentration (MIC) from 0.5% to 0.01% (Wazed Ali et al., 2011). The silver-loaded chitosan nanoparticle showed a further increase in activity (MIC 0.001%) due to the synergistic effect of Ag and chitosan nanoparticles. These particles additionally show a release mechanism as evident from a clear zone of inhibition (Figure 5.4(a—d)). 

Perlshtein, I., Applerot, G., Perkas, N., Giubert, G., Mikhailov, S., 2008. A sonochemical coating of silver nanoparticles on textile fabrics (nylon, polyester and cotton) and their antibacterial activity. Nanotechnology 19, 245705—245711. 

G. A. Martinez-Castanon, N. Nino-Martinez, F. Martinez-Gutierrez, J. R. Martinez-Mendoza, F. Ruiz Synthesis and Antibacterial Activity of Silver Nanoparticles With Different Sizes, J. Nanopart Res. 2008, v. 10,1343-1348. 

A. Shahverdi, A. Fakhimi, H. Shahverdi, S. Minaian Synthesis and Effect of Silver Nanoparticles on the Antibacterial Activity of Different Antibiotics Against Staphylococcus Aureus and Escherichia Coli, ""Nanomedicine Nanotechnology, Biology and Medicine . 2007, v. 3, iss. 2,168-171. 

A. Panacek, L. Kvitek, R. Prucek, M. Kolar, R. Vecerova, N. Pizurova, V. K. Sharma, T. Nevecna, R. Zboril Silver Colloid Nanoparticles Synthesis, Characterization, and Their Antibacterial Activity, ""J. Phys. Chem. R. 2006, v. 110,16248-16253. 

Rujitanaroj, P.O. Pimpha, N. SupaphoL P. Wound-dressing materials with antibacterial activity from electrospun gelatin fiber mats containing silver nanoparticles. Polymer 2008, 49 (21), 4723-4732. 

MubarakAli, D., Thajuddin, N., Jeganathan, K., Gunasekaran, M., 2011. Plant extract mediated synthesis of silver and gold nanoparticles and its antibacterial activity against clinically isolated pathogens. Colloids Surf B Biointerfaces 85 (2), 360—365. 

The literature confirms that attempts to clarify the mechanism of silver nanoparticle action against bacteria, viruses, and fungi have been taken. One of the most common mechanisms of nanosilver antibacterial activity is based on its natural affinity for bonding with a thiol group present in cysteine, which is a protein building material of bacterial cell walls. Consequently, the enzymatic function of the proteins is disturbed and the cellular respiration chain is interrupted. At the same time other enzymes such as NADH and succinate dehydrogenase are destroyed (Park et al., 2009). 

Dong, P.V., Ha, C.H., Binh, L.T., Kasbohm, J., 2012. Chemical synthesis and antibacterial activity of novel-shaped silver nanoparticles. Int. Nano Lett. Available from http //dx. doi.org/10.1186/2228-5326-2-9. 

Okafor, R, Janen, A., Kukhtareva, T., Edwards, V., Curley, M., 2013. Green synthesis of silver nanoparticles, their characterization, application and antibacterial activity. Int. J. Environ. Res. Public Health 10, 5221—5238. 

Elumalai, E.K., Hemachandran, J., Therasa, V.S., Thirumalai, T., David, E., 2010. Extracellular synthesis of silver nanoparticles using leaves of Euphorbia hirta and their antibacterial activities. J. Pharm. Sci. 2, 549—554. 

Antibacterial membranes with a multicomponent system containing Ag, AgBr, Ti02, and hydroxyapatite as four active components were used to obtain more efficient antibacterial activity. Additionally polyurethane nanofiber webs containing silver nanoparticles using the electrospinning technique were obtained with the stability of nanoparticles after washing cycles... 

The most popular methods of synthesizing silver nanoparticles, the antibacterial properties of silver nanoparticles, their interactions with microorganisms, and assessment of antibacterial activity are the most important issues which will be discussed here. 

It is also possible to produce antibacterial woven cotton and polyester fabrics using colloidal silver nanoparticles. Figure 1.14 clearly shows that silver nanoparticles are well-dispersed on the fibre surfaces in each fabric. In this procedure, woven cotton and polyester fabrics were padded through a certain concentration of silver colloids and squeezed to 83 % wet pick-up with a laboratory pad at a constant pressure. Textile fabrics in which the antibacterial activity shows good laundering durability can be easily obtained via the padding process using nanosized silver colloidal solutions. 

Antibacterial activity of silver nanoparticles against various microorganisms. 

A dramatic effect on Pseudomonas fouling was observed when the silver nanoparticles were immobilized on a thin-film composite PA membrane (Lee et al. 2007). SEM measurements confirmed that all Pseudomonas cells were made inactive on the modified-membrane surface, while water fluxes and salt rejections remained unchanged. High antibacterial activity toward E. coli and 5. aureus was also found with CA membranes modified with Ag nanoparticles (Chou et al. 2005). However, a significant loss of silver was found as a result of water permeation, and the antibacterial activity of the membranes disappeared after 5 days (Son et al. 2004). The loss of the entrapped silver nanoparticles was also reported for modified PS membranes, which have a high antimicrobial activity toward E. coli, P. mendocina, and the MS2 bacteriophage (Zodrow et al. 2009). 

As discussed earlier, the incidence of postoperative infection remains a major issue, often with dire conseqnences following implantation. Titanium implants are widely used clinically bnt also suffer from this issue. Therefore, surfaces with antibacterial coatings are extranely desirable. Research has demonstrated that incorporation of silver nanoparticles into titanium nanotubes enable such effects. Zhao et al. [51] showed adequate activity against planktonic bacteria within several days and preventing their subsequent growth for np to 30 days. 

An J, Zhang H, Zhang J, Zhao Y, Yuan X (2009) Preparation and antibacterial activity of electrospun chitosan/poly(ethylene oxide) membranes containing silver nanoparticles. Colloid Polym Sci 287 1425-1434... 

Singh S, Patel P, Jaiswal S, Prabhune AA, Ramana CV, Prasad BLV. A direct method for the preparation of glycohpid metal nanoparticle conjugates sophorohpids as reducing and capping agents for the synthesis of water re-dispersible silver nanoparticles and their antibacterial activity. New J Chem 2009 33 646-52. 

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