Nanoparticles

 

In nanotechnology, a particle is defined as a small object that behaves as a whole unit in terms of its transport and properties. It is further classified according to size: in terms of diameter, fine particles cover a range between 100 and 2500 nanometers, while ultrafine particles, on the other hand, are sized between 1 and 100 nanometers. Similar to ultrafine particles, nanoparticles are sized between 1 and 100 nanometers. Nanoparticles may or may not exhibit size-related properties that differ significantly from those observed in fine particles or bulk materials.^[1][2] Although the size of most molecules would fit into the above outline, individual molecules are usually not referred to as nanoparticles.

Nanoclusters have at least one dimension between 1 and 10 nanometers and a narrow size distribution. Nanopowders^[3] are agglomerates of ultrafine particles, nanoparticles, or nanoclusters. Nanometer-sized single crystals, or single-domain ultrafine particles, are often referred to as nanocrystals. Nanoparticle research is currently an area of intense scientific interest due to a wide variety of potential applications in biomedical, optical and electronic fields. The National Nanotechnology Initiative has led to generous public funding for nanoparticle

Applications of nanotubes

·         Iron oxide nanoparticles can used to improve MRI images of cancer tumors. The nanoparticle is coated with a peptide that binds to a cancer tumor, once the nanoparticles are attached to the tumor the magnetic property of the iron oxide enhances the images from the Magnetic Resonance Imagining scan. Using gold nanoparticles embedded in a porous manganese oxide as a room temperature catalyst to breakdown volatile organic compounds in air.

·         Nanoparticles coated with proteins that attach to damaged portions of arteries. This could allow delivery of drugs to the damaged regions of arteries to fight cardiovascular disease.

·         Magnetic nanoparticles that attach to cancer cells in the blood stream may allow the cancer cells to be removed before they establish new tumors.

·         A layer of closely spaced palladium nanoparticles that detect hydrogen. When hydrogen is absorbed the palladium nanoparticles swell, causing shorts between nanoparticles which lowers the resistance of the palladium layer.

·         Quantum Dots (crystalline nanoparticles) that identify the location of cancer cells in the body.

·         Combining gold nanoparticles with organic molecules to create a transistor known as a NOMFET (Nanoparticle Organic Memory Field-Effect Transistor).

·         Nanoparticles that deliver chemotherapy drugs directly to cancer cells.

·         Iron nanoparticles used to clean up carbon tetrachloride pollution in ground water.

·         Silicon nanoparticles coating anodes of lithium-ion batteries to increase battery power and reduce recharge time.

·         Silicate nanoparticles used to provide a barrier to gasses (for example oxygen), or moisture in a plastic film used for packaging. This could reduce the possibly of food spoiling or drying out.

·         Zinc oxide nanoparticles dispersed in industrial coatings to protect wood, plastic and textiles from exposure to UV rays.

·         Silicon dioxide crystalline nanoparticles filling gaps between carbon fibers strengthen tennis racquets.

·         Silver nanoparticles in fabric that kills bacteria making clothing odor-resistant.

·         Porous silica nanoparticles used to deliver chemotherapy drugs to cancer cells.