Suzanne Shelley Guest Columnist and Freelance Writer

Suzanne Shelley is a Manhattan-based freelance writer specializing in science, engineering and technology (Email: suzanneashelley”at”yahoo.com). A 16-year veteran and former Managing Editor of Chemical Engineering magazine, Suzanne now writes about a broad array of engineering and business topics related to the chemical, petroleum refining, pharmaceutical and related industries, for both corporate clients and technical trade magazines. She currently serves as Contributing Editor to several magazines, including Chemical Engineering, Chemical Engineering Progress, Turbomachinery International, and Pharmaceutical Commerce. Suzanne holds a B.S. in geology (honors) from Colgate University, and an M.S. in geology from the University of South Carolina (Columbia).

Any attempt to showcase “what’s going on in nanotechnology” will — by definition — represent just a snapshot in time, so dynamic are the ongoing discoveries and commercialization efforts related to nanoscaled developments. That being said, this roundup (prepared in late summer 2006) of promising industrial applications of nanotechnology that are moving through scaleup and commercialization helps to illustrate the dynamism of this field. It also includes a brief discussion of the imaginative ways in

The carbon nanotubes (dubbed Baytubes) that are now being produced in commercial quantities by Bayer MaterialScience AG and Bayer Technology Services are multi-walled tubes comprising up to 15 graphite layers, with a maximum mean diameter of 50 nm Credit: Reprinted with permission from Bayer Technical Services

which nanotechnology-related advances are helping the medical community to improve cancer diagnosis and treatment, and diagnostic monitoring. Meanwhile, this report also provides an overview of some the questions that remain in terms of the potential environmental, health and safety (EHS) risks that might be associated with producing and using nanoscaled materials, and some of the ongoing efforts that are underway to better assess and manage these risks.

The scientific discipline known as nanotechnology pertains to the purposeful creation, manipulation and use of matter, physical structures and engineered devices with previously unimaginable dimensions. The prefix “nano” (10^-9) refers to a billionth of something, and in the case of nanotechnology, the basic unit of measurement is the nanometer (nm), which is one billionth of one meter.

When it comes to nanotechnology-related matters, any comparisons provided to put the dimensions in context boggle the mind. For instance, consider that one nanometer equals 1/25,400,000 inch. There are 1,000 nm in a single micrometer (µm), and the diameter of an average human hair is 10,000 nm. Similarly, ten hydrogen atoms lined up in a row would fit within a single nanometer. Our DNA molecules are 2.5 nanometers wide. A typical bacterium, say E. coli, is a thousand times bigger, measuring between 1,000 and 2,000 nm, while certain viruses, like the ones that cause the common cold measure around 20 nanometers.

Viewed as an academic curiosity just two decades ago, nanotechnology is now widely regarded as a key enabling technology of the 21^st century. Today, nanoscaled materials and nanotechnology-related manufacturing techniques are already being used to produce composite materials with improved electroconductivity, catalytic activity, hardness, scratch resistance and self-cleaning capabilities, and consumer products (such as cosmetics and sunscreens) that have improved aesthetic appeal and efficiency. Nanotechnology-related applications are also being developed to improve the performance of gas sensors and other industrial and medical monitoring devices, to increase the activity of various catalysts, and to produce improved fuel cells and more lightweight and longer-lasting batteries.

Thanks to the inverse relationship between particle size and surface area, drastically size-reduced nanoparticles have an extraordinary amount of available surface area, and at these dimensions, many materials —including metals, metal oxides, various forms of silica, clays and novel carbon compounds — demonstrate a range of favorable physical properties and characteristics compared to macroscopic particles of the same material. These new properties open the door for a diverse array of novel applications and end products.

Carbon nanotubes are said to have a tensile strength 100 times that of steel, but at only one-sixth the weight Credit: Reprinted with permission from Nanomix, Inc.

For instance, compared to macroscopic particles of the same materials, nanoscaled particles of many materials often demonstrate increased hardness and tensile strength, favorable melting point and magnetic properties, thermal and electrical conductivity, surface chemistry effects (which can improve particle dispersibility and reactivity, and yield higher chemical conversion rates and greater catalytic activity), and photonic behavior (i.e., functionality that changes in the presence of light of varying wavelengths). The desire to exploit these remarkable material properties to bring functional advantages to many industrial and medical applications is a fundamental driver of nanotechnology-related R&D efforts.

In recent years, working with countless materials, the scientific, engineering and medical communities have verified the novel, size-dependent properties and phenomena that occur (or are vastly improved) in the nanometer-range, and they continue working to perfect the techniques needed to reliably produce or manufacture these tiny structures. Efforts are also under way to develop advanced dispersion techniques to minimize agglomeration, which can undermine the beneficial properties of these ultrasmall particles.

The private sector is not the sole domain of nanotechnology-related research and development efforts. The governments of many nations are also devoting considerable resources to utilizing putting nanotech-related advances to work. In the U.S., a primary unifying force has been the National Nanotechnology Initiative (NNI), a long-term research and development program that coordinates the nanotechnology-related activities of 22 departments of the U.S. government, such as the National Science Foundation, Dept. of Defense, Dept. of Energy, National Institutes of Health, National Institute of Standards, and National Aeronautical Space Administration, and other independent agencies. It was first proposed in 2000, during the Clinton Administration, and was signed into law in 2003 by President George H.W. Bush (The “21^st Century Nanotechnology R&D Act”).

President George W. Bush’s 2007 Budget provides over $1.2 billion for nanotechnology-related R&D by the multi-agency NNI members. This nearly triples the annual nanotechnology-related funding the NNI participants have received since the 2001.

As they leave the reactor, nanotubes resemble a tangled web Credit: Reprinted with permission from Arkema

Since the NNI was established, more than 40 other countries have announced priority nanotechnology programs, including Japan, Germany, China, Taiwan and Korea.