Biomedical Engineering Reference
In-Depth Information
for optimal performance with desirable optical, magnetic, environment-sensitive, or target-specifi c
properties, leading to controlled delivery patterns such as sustained or environment-responsive release
or targeting drug delivery. It should be noted that in addition to those single component porous nano-
materials, composite or hybrid porous nanomaterials are fabricated with multiple components chosen
from various soft and inorganic materials,
137,138
which adds more fl exibility to the design and engineer-
ing of advanced delivery systems. In addition to the controlled drug delivery application, porous nano-
structured materials are under extensive investigation for possible use in other biomedical applications
such as tissue engineering, imaging, and biosensing. Efforts toward developing multifunctional smart
systems suitable for manifold applications are in full swing.
60,96,139-141
Since 1970, pharmaceutical research has come a long way from drug discovery by empiri-
cism and happenstance to the more sophisticated and rational investigation. Nanotechnology, as a
relatively new player in this fi eld, has demonstrated immense potential and brought keen promise
for more effective methods of drug and therapy with more sophisticated and smart functionality
enabled by engineering at the nanoscale. In addition to the applications discussed above, the possi-
bilities of use of nanomaterials in the pharmaceutical fi eld include superparamagnetic drug-loaded
and peptide-coated nanoparticles that not only home into tumors but also amplify their own hom-
ing,
139
red blood cell hydrogel mimics with controllable circulating time, near-infrared absorbing
metal nanoshells for photothermal cancer therapy and tissue-welding,
142,143
fl uorescent quantum
dots for diagnostics, and
in vivo
imaging agents during surgery.
144
In all of these systems, the high
surface to volume ratio of the nanostructures makes them easily surface modifi ed and thus sensitive
for effi cient targeting. Advances in nanostructured materials should pave the way for more oppor-
tunities in and contributions to diagnostics and therapeutics.
ACKNOWLEDGMENTS
The authors gratefully acknowledge helpful discussions with Prof. Michael J. Sailor of the Depart-
ment of Chemistry and Biochemistry at the University of California, San Diego.
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