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already on the market. [43]
The nanomedicine research is a goal and needs a
long-term plan, which is to quantitatively
characterize the molecular-scale components, or
nanomachinery, of living cells and to precisely
control and manipulate these molecular and
supramolecular assemblies in living cells to improve
human health. Nanomedicine will exploit and build
upon other research findings in nanotechnology and
apply it to the study of molecular systems in living
cells that contain a multitude of nanoscale structures,
such as membrane transporters, processes such as
self-assembly of protein–nucleic acid complexes, and
nanomachines such as molecular motors. The
benefits of nanomedicine include dramatically
expanded knowledge of the human genome, a greater
understanding of the pathophysiology of specific
diseases at the molecular scale, more specific
treatment of diseases, and the ability to understand
the dynamic behavior of dysfunctional cellular
machinery in the context of the total cell
machinery. [44] Robert A and Freitas Jr given an
overview of this rapidly expanding and exciting
nanomedicine field. Over the next 5 to 10 years,
nanomedicine will address many important medical
problems by using nanoscale-structured materials and
simple nanodevices that can be manufactured today.
Many approaches to nanomedicine being pursued
today are already close enough to fruition that it is
fair to say that their successful development is almost
inevitable, and their subsequent incorporation into
valuable medical diagnostics or clinical therapeutics
is highly likely and may occur very soon. [45]
The science of nanomedicine exploits and builds
upon novel research findings in nanotechnology,
biology, and medicine; it unifies the efforts of
scientists, engineers, and physicians determined to
apply their latest research results to translational and
clinical medicine by developing novel approaches
and a better understanding of solutions to
health-relatedissues, ultimately improving the quality
of life. The last few years have seen unprecedented
advances in the field of biology. The decoding of the
human genome coupled with improving gene
transfection technologies offer great opportunities for
treating illnesses. In analysis and diagnosis,
lab-on-a-chip methods have surpassed earlier ex-vivo
and in-vivo detection methods while also aiding
toxicology efforts. In medicine, improvements in
targeted drug delivery, imaging, and therapy have led
to such successful interventions in cancer therapies.
[46]
Although there are only a few FDA-approved
nanopharmaceuticals on the market today, these
formulations are already impacting medicine and
promise to alter healthcare. Based on their ability to
reduce time-to-market, extend the economic life of
proprietary drugs and create additional revenue
streams, nanopharmaceuticals should greatly impact
medical practice and healthcare. However, if this is to
happen effectively, there are a few key biological
requirements for nanopharmaceuticals to fulfill: (1)
they must exhibit stealth qualities to evade
macrophage attack and the immune response; (2) be
nontoxic and traceable; (3) display effective
pharmacokinetic properties; (4) be biodegradable
following systemic administration through any route
(but the polymer must protect the embedded active);
and (5) they must be selective to be effective in
targeting specific tissue sites. Srikumaran Melethil
(Chair and Professor of Pharmaceutical Sciences at
the University of Findlay, Findlay, OH) discussed the
metabolic fate of nanopharmaceuticals upon delivery
to the human body, and presented pharmacokinetic
data relating to numerous nanoparticulate drugs and
highlighted the critical role of the FDA in
nanomedicine. According to him, further knowledge
of how the human body transports, distributes and
clears nanoparticles via the vascular and lymphatic
systems (i.e.,biodistribution of nanoparticles) is also
needed to get a handle on metabolic and toxicity
issues. Nanomedicine will eventually become an
integral part of mainstream medicine and a standard
in the drug industry. For example, the market impact
of nanopharmaceuticals on the pharmaceutical and
biotech industries is already being felt. However, for
nanomedicine to be a viable commercial entity,
desperately needed reforms to overhaul the PTO
along with clearer regulatory guidelines and safety
standards from federal agencies such as the FDA will
be needed.
Ethical question of nanomedicine is an important
issue. Ginger Gruters (The President's Council on
Bioethics, Washington, DC) presented on ethical
considerations that are likely to play a significant role
in nanomedicine, and stated that, as with other
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