Biomedical Engineering Reference
In-Depth Information
Cosmetics, fuel
additives
Chemical synthesis
Particle molecules
Crystals, films, and
tubes
Self-assembly
Displays
Experimental atomic
or molecular devices
Positional assembly
Quantum well lasers
Computer chips
MEMS
Electronic devices
chip masks
Lithography
Precision-engineered
surfaces
Cutting, etching, and
grinding
FIGURE 1.2
Bottom-up and top-down techniques in manufacturing nanoparticles.
matrix. NPs, nanospheres, or nanocapsules can be obtained in various forms, such as particles or
vesicles, based on the preparation method. Major ambitions in fabricating NPs as delivery car-
riers are to control the particle size, surface properties, and the release of therapeutics in order
to accomplish the site-specific targeting of the drug at a therapeutically optimal rate and dose
regimen. NPs can be made up of several materials, including polymers, metals, and ceramics.
According to their methods of manufacturing and the materials used, NPs can adopt differ-
ent shapes and sizes with specific properties. Many other types of NPs are in several stages of
development as drug delivery carriers, including lipid-based carriers such as liposomes, lipid
emulsions, lipid-drug complexes, polymer-drug conjugates, polymer microspheres, micelles,
and various ligand-targeted carriers such as immunoconjugates (Allen 2002, LaVan et al. 2003,
Liu et al. 2000, Moghimi et al. 2001).
1.1.2 g
eNesIs
of
the
f
Ield
Although nanotechnology as a field has developed recently, the concept has been present since
much earlier. The synthesis and use of gold NPs predates the age of peer-reviewed literature. For
example, artists have been utilizing colloidal gold, otherwise referred to as a gold NP solution, to
create colors for pottery from the Ming dynasty and stained glass windows in medieval churches
(Daniel and Astruc 2004).
The first published report on colloidal gold dates back to a celebrated, 1857 work by Faraday,
although earlier unpublished experiments are likely (Faraday 1857). In 1959, Richard Feynman, an
American physicist and Nobel Prize winner, envisioned the idea of manipulating particles or materi-
als at a molecular and atomic scale in his presentation titled “There's Plenty of Room at the Bottom”
to the American Physical Society's annual meeting. During his talk, he presented facts for generat-
ing nanoscale machines to manipulate, control, and image materials at the atomic level. However,
the term “nanotechnology” was coined in 1974, more than a decade later, by Norio Taniguchi, a
