Tese_Tânia Vieira.pdf - Ubi Thesis
Tese_Tânia Vieira.pdf - Ubi Thesis
Tese_Tânia Vieira.pdf - Ubi Thesis
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Chapter I - Introduction<br />
Besides its antimicrobial activity, it has been recently found that AgNPs reduce cytokine<br />
release (Guidelli et al. 2011), decreasing lymphocyte and mast cell infiltration and also induce<br />
apoptosis of inflammatory cells (Chaloupka et al. 2010). These characteristics of AgNPs are<br />
responsible for the anti-inflammatory effect and contributes for accelerating the<br />
epithelialization by over 40% and, as a consequence, accelerate wound healing (Lu et al. 2008;<br />
Chaloupka et al. 2010; Kalishwaralal et al. 2010).<br />
1.3.1. Applications of silver nanoparticles<br />
The properties presented by AgNPs make them good candidates to be used in different<br />
applications, like in electronics and in sensor design based on the surface-enhanced Raman<br />
spectroscopy (SERS) (Badawy et al. 2010; Parashar et al. 2011). Moreover, these nanoparticles<br />
have been used in a number of medical applications (Arora et al. 2009), due to the antimicrobial<br />
activity owned by the silver-based compounds containing ionic silver or metallic silver (Panác ek<br />
et al. 2006; Arora et al. 2008).<br />
Some applications of silver and AgNPs are presented in figure 1. In the case of silver, it is<br />
used in the form of AgNO 3 solutions to perform cauterization, in order to stop epistaxis and the<br />
growth of post-traumatic granulomas (Chaloupka et al. 2010). AgNO 3 is also used to prevent<br />
some infections and to promote an anti-inflammatory effect in the procedure of pleurodesis<br />
(Chaloupka et al. 2010). Silver is also used in the form of silver sulfadiazine cream to apply in<br />
ulcers and burns to promote the skin regeneration (Chaloupka et al. 2010).<br />
AgNPs have been used as coating material for medical purposes, orthopedic, vascular or<br />
dental graft materials (Panác ek et al. 2006; Ruparelia et al. 2008; Vertelov et al. 2008),<br />
indwelling catheters (Vasilev et al. 2010), and arthroplasty (Panác ek et al. 2006). AgNPs can be<br />
impregnated in wound dressings (Xu et al. 2011), in diabetic ulcers (Ip et al. 2006; Li et al.<br />
2011), in chronic ulcers, and in traumatic injuries in order to prevent infections and enhance<br />
wound repair (Ip et al. 2006). Some medical products containing AgNPs available in the market,<br />
as wound dressings and catheters, are presented in table 1 (Arora et al. 2009; Chaloupka et al.<br />
2010).<br />
Moreover, silver can also be employed to eliminate microorganisms on textile products,<br />
food storage containers, cosmetics in the form of nanogels and nanolotions, contraceptive<br />
devices, and they can be used for water filtration too (Monteiro et al. 2009; Shameli et al. 2010;<br />
Vasilev et al. 2010; Mirzajani et al. 2011).<br />
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