Biomedical Engineering Reference
In-Depth Information
hazardous nanomaterials or in the form of new or strengthened ethical or
societal impacts. The scope of this topic is to review and assess recent scien-
tific progress in applications of nanotechnology for medical, environmental,
agrifood, and water applications—as well as insight in potential hazards of
and exposure to engineered nanostructured materials and in nanobioethi-
cal and societal issues. The aim is to enable better insight into the potential
benefits and risks nanotechnology may offer for human health.
1.1 What Is Nanotechnology?
Definitions of nanotechnology depend on the disciplinary background and
professional working environment of the person using the term. The most
common and broadest definition is, “Materials and devices having func-
tional features with a length scale between one-tenth and several hundreds
of nanometers, in one, two, or three dimensions.” One-tenth of a nanome-
ter, or 1 Å, is the diameter of a hydrogen atom, the smallest type of atom
(10
-10
m). Nanotechnology therefore does not deal with subatomic particles.
In the 1990s, when nanotechnology emerged as a separate area of research, a
hundred nanometers was considered the smallest size of functional features
on a microchip. Nanotechnology was seen as a possible way to shrink those
features beyond the limits of conventional lithography. Nanotechnology
may be rooted in physics and mechanical (or precision) engineering but the
research done in nanoscience and technology is inherently interdisciplinary
in character, and includes at least parts of chemistry, biology, and materials
science, if not more disciplines. Most real applications including nanomateri-
als and technologies can only be developed by interdisciplinary collabora-
tions involving, for example, chemists and physicists.
Given this variety of subdomains in nanotechnology, one may wonder if
nanotechnology exists at all. This vagueness of the term is currently prob-
lematic; however, when it was introduced in the 1990s, the same fuzziness of
the boundaries of nanotechnology was deemed desirable by the policymak-
ers who invented it. They wanted to stimulate interdisciplinary cooperation
between scientists from different disciplines working at the nanometer scale
because it was generally believed that innovation takes place at the bound-
aries between disciplines. The policy makers offered funding for scientists
willing to cooperate with colleagues from other disciplines. Since the begin-
ning of the twenty-first century, more and more countries have been active
in nanoscience and nanotechnology. Several governments are investing con-
siderable amounts in nanotechnology research, an investment that has grad-
ually been overtaken by private investments according to several business
consultants whose methods of data collection are not transparent. According
to a survey by the Organization for Economic Cooperation and Development
