Pharmaceutical Manufacturing Handbook: Production and

1250 NANOTECHNOLOGY IN PHARMACEUTICAL MANUFACTURING
as materials, manufacturing, electronics, medicine, health care, energy, environment,
biotechnology, information technology, and national security. It is widely felt
that nanotechnology will lead to the next industrial revolution [4] .
The idea of nanotechnology was fi rst presented by physicist Richard Feynman.
His lecture entitled “ Room at the Bottom ” in 1959 unveiled the possibilities available
in the molecular world. Because bulk matter is built of so many atoms, there
is a remarkable amount of space within which to build. Feynman ’ s vision spawned
the discipline of nanotechnology, and his dream is now coming true [5] . Along with
continually increasing multidisciplinary applications of nanotechnology, many new
terms with nanotechnology characteristics appear, for example, nanomechanics [6] ,
nanooptics [7] , nanoelectronics [8] , nanochemistry [9] , nanomedicine [10] , nanobiotechnology
[5, 11] , nanolithography [12] , nanoengineering [13] , nanofabrication [14] ,
and nanomanufacturing [15] . A very broad sense term, nanoscience is often used.
More and more new words with nano as a prefi x will be created to fi t for the nowadays
nanoworld. In fact, applications of nanotechnology in medicine and biotechnology
have made great progresses in the recent two decades.
All developed countries including the United States, Japan, and Europe invest
a great deal of money in nanotechnology. The National Science Foundation (NSF)
of the United States is a leading agency in the national nanotechnology initiative,
funding nanotechnology investments at $ 373 million in 2007, an increase of 8.6%
from 2006 and of nearly 150% since 2001 [16] . Developing countries such as China
and India also invest a lot in this increasing fi eld so as not to stay far behind developed
countries. Cancer therapy and research are hottest applied fi elds of bionanotechnology.
In 2004, the U.S. National Cancer Institute (NCI) launched a $ 144
million cancer nanotechnology initiative, and the investment increased largely in
the following two years [17] . At the same time, investment from public resources
or companies is much higher than that from governments.
The application of nanotechnology in pharmacy has a long history, before the
prevalence of the nanoconcept. It was well known 50 years ago that very small drug
particles have a high solubility in solvents, resulting from the too large surface area
when particle size decreased to a very small level, that is, the nanoscale, although
this scale had not been mentioned yet. In 1965, Banham created liposomes (lipid
vesicles) consisting of phospholipids which had a small size, typically ranging from
10 nm to several micrometers. It was soon found that liposomes were excellent drug
carriers, and more importantly they had site - specifi c distribution capability in vivo
depending on their size. It is well known that nanosized liposomes are inclined to
deposit in the mononuclear phagocyte system (MPS), including liver, spleen, lung,
and marrow. Therefore, nanotechnology was introduced in drug delivery very long
ago. Now various nanomaterials are used to deliver drugs, and some nanosystems
delivering active agents are available on the market. Undoubtedly, nanotechnology
plays a key role in future pharmaceutical development and pharmacotherapy.
7.2.2
7.2.2.1
NANOMATERIALS
Types of Nanomaterials
Nanomaterial is a general term. Although nanomaterials are defi ned as solid or
liquid materials at the nanoscale, the nanoscale range remains unclear. Many scien-