NANOTECH INNOVATIONS

As technology enters the close of the first decade this millennium, nanotechnology becomes increasingly more important in product development. Processors, chipsets, memory, displays and other electronics are marching toward the use of nanotech at and astonishing rate. In the U.S., we're already developing technology manufactured at the nanometer and sub-nanometer (picometer) level.

Carbon nanotubes, a high strength and versatile material composed of molecular configurations of pure carbon, may be the key to next generation technology in everything from the space elevator to high-speed processors. But outside of research, nanotech is here already. Research advocates have identified more than 400 consumer products in the U.S. labeled as "nano-based."  Some of these products, like microprocessors, pose relatively little risk to consumer, but the long term effects of other products like nano-aerosols is a bit less understood.  Additionally, the manufacturing by-products of these products are completely unregulated or monitored.

Nanotech and the production of nano-based devices create a type of pollution that is so small, it is extremely difficult to detect or contain. Researchers are afraid of the effect that nanopollution might have on humans, animals and other living organisms.

Nanoparticles are so small that they easily penetrate cells, a handy technique when geneticists attempt to modify genes when done intentionally. However, even when deliberate, the body detects foreign objects and creates phagocytes to break down invading material. Of course, if the body's phagocytes are busy digesting nanoparticles, the cells can't break down bacteria or other debris inside the body. Quantum dots, or nanoparticles used for semiconductors, are so small that they will actually pass right through cell walls -- yet we have relatively little research on what occurs when quantum dots interact with the human body.

Nanotechnology has wide applications in many fields, especially in the biological sciences and medicine. Nanomaterials are applied as coating materials or in treatment and diagnosis. Nanoparticles such as titania, zirconia, silver, diamonds, iron oxides, carbon nanotubes, and biodegradable polymers have been studied in diagnosis and treatment. 

Many of these nanoparticles may have toxic effects on cells. Many factors such as size, inherent properties, and surface chemistry may cause nanoparticle toxicity. There are methods for improving the performance and reducing toxicity of nanoparticles in medical design, such as biocompatible coating materials or biodegradable/biocompatible nanoparticles. Most metal oxide nanoparticles show toxic effects, but no toxic effects have been observed with biocompatible coatings. Biodegradable nanoparticles are also used in the efficient design of medical materials,

The materials based on metal nanoparticles have found many applications in chemistry, physics and biology. The nanoscale association of inorganic colloids with polymers affords hybrid materials that combine the properties of both components. In such a way, a catalytic, optical and electronic features of inorganic colloids might be combined with the characteristics of polymers that offer many advantages in processing. The main problems in this field focus on the development of effective methods for the synthesis and stabilization of metal nanoparticles.

In this paper we consider the methods including simultaneous formation of the polymer matrix and metal nanoparticles. One of them is based on the thermal transformations of metal-containing monomers which includes dehydration, solid phase polymerization, and decomposition of the product which proceed sequentially at varied temperature ranges. The thermolysis resulted in the synthesis of metal nanoparticles with narrow size distribution (the mean particle diameter of 5-10 nm) in the polymer matrix . The topography of the initial compounds and metallopolymer composites obtained as well as their composition are analyzed by optical and electron microscopy. The initial stage of nanoparticle nucleation in metallopolymer system was studied using the EXAFS spectroscopy.

The novel approach for synthesis of noble metal polymer-immobilized catalysts via frontal polymerization of acrylamide complexes into surface of inorganic oxides is elaborated. Electron microscopy studies indicate that such polymer-inorganic composites contain Pd nanoparticles which are homogeneously distributed in the polymer matrix. The hybrid inorganic polymer nanocomposites on the base of titanium oxide and methacrylate polymers containing transition metal ions were obtained and characterized using sol-gel synthesis.

A number of clinical applications of nanobiotechnology, such as disease diagnosis, target-specific drug delivery, and molecular imaging are being laboriously investigated at present. Some new promising products are also undergoing clinical trials. Such advanced applications of this approach to biological systems will undoubtedly transform the foundations of diagnosis, treatment, and prevention of disease in future. Some of these applications are discussed below.

Nanomembranes are commonly made from organic polymer based nanocomposites with a thickness less than 100nm. Such nanomembranes include organic polymers combined with a mesh of silica nanoparticles. The size of the holes in the mesh restricts or allows the passage of different sized molecules.

Nanomembranes are commonly fabricated using Layer-by-Layer (LbL) assembly methods. This method give precise control over the in plane composition of the membrane and allows for the addition of a range of components to be added to the membrane. These components include nanoparticles and nanotubes that can tailor the mechanical, optical and electronic properties of the nanomembrane.

Applications for nanomembranes include :

CNMs:
Carbon nanomembranes (CNMs) are similar to plastic films, but only 1 nanometer (1 millionths of 1 millimeter) in thickness. CNMs are the thinnest man-made polymeric membranes. Their thickness is fifty times thinner than commercial inorganic membranes and about five times thinner than biological lipid bilayers. CNMs constitute a new class of material with interesting properties that promise to lead to innovative products in many fields: