Transport Phenomenon of Nanoparticles in Animals and Humans

Nanoparticles (NPs) are microscopic objects with at least one dimension less than 100 nm. These were first discovered by Michael Faraday in 1857 when he prepared gold nanoparticles and observed that nanostructured gold produced red color. This distinct feature of nanoparticles could be due to very small size. NPs are very small compared to the wavelengths of light, hence absorb light in the blue-green portion of the spectrum (~450 nm) and reflect the red light (~700 nm) thus yield a rich red color. NPs also possess very high surface to mass ratio that could be utilized in several application areas wherein a very high surface area is required. Nanoparticles witnessed tremendous growth in research and application areas especially in medicine in twentieth century after discovery of carbon nanotubes in 1991. Nanoparticles have been explored in medicine as targeted delivery carriers to deliver macromolecules such as proteins, enzymes, to the target organ up to cellular levels. Of late, these carriers have been employed to treat several tumors owing to its capacity to deliver chemotherapeutic agents to the tumor cells only thus improving efficacy and minimizing side effects of anticancer agents.