Nanotechnology: History and future.

Human dreams and imagination often give rise to new science and technology. Nanotechnology, a 21st-century frontier, was born out of such dreams. Nanotechnology is defined as the understanding and control of matter at dimensions between 1 and 100 nm where unique phenomena enable novel applications. Although human exposure to nanoparticles has occurred throughout human history, it dramatically increased during the industrial revolution. The study of nanoparticles is not new. The concept of a ‘‘nanometer’’ was first proposed by Richard Zsigmondy, the 1925 Nobel Prize Laureate in chemistry. He coined the term nanometer explicitly for characterizing particle size and he was the first to measure the size of particles such as gold colloids using a microscope. Modern nanotechnology was the brain child of Richard Feynman, the 1965 Nobel Prize Laureate in physics. During the 1959 American Physical Society meeting at Caltech, he presented a lecture titled, ‘‘There’s Plenty of Room at the Bottom’’, in which he introduced the concept of manipulating matter at the atomic level. This novel idea demonstrated new ways of thinking and Feynman’s hypotheses have since been proven correct. It is for these reasons that he is considered the father of modern nanotechnology. Almost 15 years after Feynman’s lecture, a Japanese scientist, Norio Taniguchi, was the first to use ‘‘nanotechnology’’ to describe semiconductor processes that occurred on the order of a nanometer. He advocated that nanotechnology consisted of the processing, separation, consolidation, and deformation of materials by one atom or one molecule. The golden era of nanotechnology began in the 1980s when Kroto, Smalley, and Curl discovered fullerenes and Eric Drexler of Massachusetts Institute of Technology (MIT) used ideas from Feynman’s ‘‘There is Plenty of Room at the Bottom’’ and Taniguchi’s term nanotechnology in his 1986 book titled, ‘‘Engines of Creation: The Coming Era of Nanotechnology.’’ Drexler proposed the idea of a nanoscale ‘‘assembler’’ which would be able to build a copy of itself and of other items of arbitrary complexity. Drexler’s vision of nanotechnology is often called ‘‘molecular nanotechnology.’’ The science of nanotechnology was advanced further when Iijima, another Japanese scientist, developed carbon nanotubes. The beginning of the 21st century saw an increased interest in the emerging fields of nanoscience and nanotechnology. In the United States, Feynman’s stature and his concept of manipulation of matter at the atomic level played an important role in shaping national science priorities. President Bill Clinton advocated for funding of research in this emerging technology during a speech at Caltech on January 21, 2000. Three years later, President George W. Bush signed into law the 21st Century Nanotechnology Research and Development Act. The legislation made nanotechnology research a national priority and created the National Technology Initiative (NNI). Today, the NNI is managed within a framework at the top of which is the President’s Cabinet-level National Science and Technology Council (NSTC) and its Committee on Technology. The Committee’s Subcommittee on Nanoscale Science, Engineering, and Technology (NSET) is responsible for planning, budgeting, implementation, and review of the NNI and is comprised of representatives from 20 US departments and independent agencies and commissions (Table 1).