State-Of-The-Science Review: Everything NanoSilver and More
Silver has been valued throughout history for many of its properties that are useful to humans. It is used as a precious commodity in currencies, ornaments, jewelry, electrical contacts and photography, among others. One of the most beneficial uses of silver has been as a potent antibacterial agent that is toxic to fungi, viruses and algae. Silver has long been used as a disinfectant; for example, the metal has been used in treating wounds and burns because of its broad-spectrum toxicity to bacteria as well as because of its reputation of limited toxicity to humans. In nanotechnology, a nano particle is defined as a small object or particle that behaves as a whole unit in terms of its transport and properties. Nanotechnology takes advantage of the fact that when a solid material becomes very small, its specific surface area increases, which leads to an increase in the surface reactivity and quantum-related effects. The physical and chemical properties of nanomaterials can become very different from those of the same material in larger bulk form. Nanomaterials (such as nanotubes and nanorods) and nanoparticles are particles that have at least one dimension in the range of 1 to 100 nm. Nanoparticles are classified solely based on their size, and may or may not exhibit size-related properties that differ significantly from those observed in bulk materials (ASTM, 2006; Buzea et al., 2007). Due to the properties of silver at the nanoscale, nanosilver is nowadays used in an increasing number of consumer and medical products. Nanomaterials are nanoparticles that have special physicochemical properties as a result of their small size (Buzea et al., 2007).