18-06-2012, 11:32 AM
Current Status of Nanomedicine and Medical Nanorobotics
Current Status of Nanomedicine.pdf (Size: 1.32 MB / Downloads: 47)
NANO TECHNOLOGY AND NANOMEDICINE
Annual U.S. federal funding for nanotechnology R&D
exceeded $500 million in 20021 reaching $849 million in
FY 20042 and could approach $1 billion in next year’s
budget.The European Commission has set aside 1.3 billion
euros for nanotechnology research during 2003–
2006,3 with annual nanotechnology investment worldwide
reaching approximately $3 billion in 2003.The worldwide
market for nanoscale devices and molecular modeling
should grow 28%/year, rising from $406 million in
2002 to $1.37 billion in 2007, with a 35%/year growth rate
in revenues from biomedical nanoscale devices.4
MEDICAL NANOMATERIALS AND NANODEVICES
Nanopores
Perhaps one of the simplest medical nanomaterials is a surface
perforated with holes, or nanopores.In 1997 Desai
and Ferrari created what could be considered one of the earliest
therapeutically useful nanomedical devices,15 employing
bulk micromachining to fabricate tiny cell-containing
chambers within single crystalline silicon wafers.The
chambers interface with the surrounding biological environment
through polycrystalline silicon filter membranes
which are micromachined to present a high density of uniform
nanopores as small as 20 nanometers in diameter.
MICR OSCALE BIOLOGICAL ROBOTS
One convenient shortcut to nanorobotics is to engineer natural
nanomachine systems—microscale biological viruses
and bacteria—to create new, artificial biological devices.
Efforts at purely rational virus design are underway
but have not yet borne much fruit.F or example, Endy
et al.112 computationally simulated the growth rates of bacteriophage
T7 mutants with altered genetic element orders
and found one new genome permutation that was predicted
to allow the phage to grow 31% faster than wild
type; unfortunately, experiments failed to confirm the predicted
speedup.Better models are clearly needed.113 114
Nevertheless, combinatorial experiments on wild type T7
by others115–117 have produced new but immunologically
indistinguishable T7 variants which have 12% of their
genome deleted and which replicate twice as fast as wild
type.