1. INTRODUCTION
Biomedical sciences being a life and dynamic subject continuously explores new
frontiers, though I must confess that it is very slow in incorporating this findings into
every day practice. The reasons for the slow incorporation ~of new development into
medicine are basically three. As a subject dealing with humans, experimentations are
strictly controlled by ethical, moral and religious guidelines and respect for human life.
The second reason is that training in medicine being through apprenticeship; young
graduates guard jealously what they’ve learnt from the masters” and rarely deviate from
the norms set by the masters to avoid cristisms and back lash from the masters. Thirdly it
takes years of trial from animal to human subjects before it certified free from dangers.
The fears of side effect and adverse out of new drugs are exemplified by the thousands of
babies born with phocomelia following the use of thalidomide.
Because of above reasons experimental medicine is almost light years ahead of clinical
practice.
Examination: The first step in any treatment process. It includes individual’s medical
history, personal function and structural baselines, and current complaints. In classical
medicine interview and observation have long been the cornerstone of examination.
Advancing technology has brought plethora of tests that contribute to accurate diagnosis.
Diagnosis: The determination of the cause and nature of a disease in order to provide a
logical basis for treatment and prognosis traditionally the diagnostic process begins with
a thorough history taken from the patient and relevant physical examination. Often this
sufficed to make a confident diagnosis, but the cause of some illnesses remained
uncertain without recourse to additional information such as blood tests or radiological
examinations.
Prognosis and treatment: Prognosis Is a judgment or forecast, based upon a correct
diagnosis, of the future course of a disease or injury, and of the patients prospects for
partial or full recovery. But prognosis Is a function of treatment as well as disease. From
the post-Hippocratic era through the 18th century, treatments were almost purely
empirical and often did more harm than good. During the 19th and early 20th centuries,
treatments were scientific but largely homeostatic—the medical intervention was rational
but served mainly to assist the body in healing itself. Throughout the remainder of the
20th century, truly curative treatments began to rescue some patients from conditions
from which their unaided bodies would not have been able to recover.
Validation and prophylaxis: A proper therapeutic protocol will include a procedure for
follow-up to ensure that the prescribed treatment was correctly executed with good
results. This step is often neglected in order to save costs and may be considered
unimportant by some practitioners because approximately 80%-90% of all illnesses,
which take patients to the doctor, are self-curing or self-limiting. For example, the
common cold, most infectious diseases and many minor injuries are problems that
usually will resolve on their own even with no treatment. In these cases the purpose of
treatment is not to provide a cure, but rather to speed the healing process, improve
comfort, and avoid complications. Prophylaxis is the prevention of disease, typically
including patient education, immunization programs, amelioration of occupational
hazards, and other preventive and public health measures.

2. LIMITATIONS OF CURRENT MEDICINE
When the body’s working, building, and battling goes awry, we turn to medicine for
diagnosis and treatment. Today’s methods, though, have obvious shortcomings.
A. Crude Methods: Diagnostic procedures vary widely, from asking a patient questions,
through looking at X-ray shadows, through exploratory surgery and the microscopic and
chemical analysis of materials from the body. Doctors can diagnose many ills, but others
remain mysteries. Even a diagnosis does not imply understanding: doctors could diagnose
infections before they knew about germs, and today can diagnose many syndromes with
unknown causes. After years of experimentation and unfold loss of life, they can even
treat what they don’t understand a drug may help, though no one knows why.
Leaving aside such therapies as heating, massaging, irradiating, and so forth, the two
main forms of treatment are surgery and drugs. From a molecular perspective, neither is
sophisticated.
Surgery is a direct, manual approach to fixing the body, now practiced by highly trained
specialists. Surgeons sew together torn tissues and skin to enable healing, cut out cancer,
clear out clogged arteries, and even install pacemakers and replacement organs. It’s
direct, but if can be dangerous: anesthetics, infections, organ rejection, and missed cancer
cells can all cause failure. Surgeons lack fine-scale control. The body works by means of
molecular machines, most working inside cells. Surgeons can see neither molecules nor
cells, and can repair neither.
Drug therapies affect the body at the molecular level. Some therapies - like insulin for
diabetics - provide materials the body lacks. Most - like antibiotics for infections -
introduce materials no human body produces. A drug consists of small molecules; in our
simulated molecular world, many would fit in the palm of your hand. These molecules
are dumped into the body (sometimes directed to a particular region by a needle or the
like), where they mix and wander through blood and tissue. They typically bump into
other molecules of all sorts in all places, but only stick to and affect molecules of certain
kinds.
Antibiotics like penicillin are selective poisons. They stick to molecular machines in
bacteria and jam them, thus fighting infection. Viruses are a harder case because they are
simpler and have fewer vulnerable molecular machines. Worms, fungi, and protozoa are
also difficult, because their molecular machines are more like those found in the human
body, and hence harder to jam selectively. Cancer is the most difficult of all. Cancerous
growths consist of human cells, and attempts to poison the cancer cells typically poison
the rest of the patient as well.
Other drug molecules bind to molecules in the human body and modify their behavior.
Some decrease the secretion of stomach acid, others stimulate the kidneys, many affect
the molecular dynamics of the brain. Designing drug molecules to bind to specific targets
is a growth industry today, and provides one of the many short-term payoffs that is
spurring developments in molecular engineering.
B. Limited Abilities: Current medicine is limited both by its understanding and by ifs
fools. In many ways, it is still more an art than a science. Mark Pearson of Du Pont points
out, “In some areas, medicine has become much more scientific, and in others not much
at all. We’re still short of what I would consider a reasonable scientific level. Many

3. people don’t realize that we just don’t know fundamentally how things work. It’s like
having an automobile, and hoping that by taking things apart, we’ll understand something
of how they operate. We know there’s an engine in the front and we know it’s under the
hood, we have an idea that it’s big and heavy, but we don’t really see the rings that allow
pistons to slide in the block. We don’t even understand that controlled explosions are
responsible for providing the energy that drives the machine.
Better tools could provide both better knowledge and better ways to apply that
knowledge for healing. Today’s surgery can rearrange blood vessels, but is far too coarse
to rearrange or repair cells. Today’s drug therapies can target some specific molecules,
but only some, and only on the basis of type. Doctors today can’t affect molecules in one
cell while leaving identical molecules in a neighboring cell untouched because medicine
today cannot apply surgical control to the molecular level.
NANOTECHNOLOGY
The possibility of nanorobotics and nanotechnology was first proposed by Nobel prize
winner Richard Feynman in his talk in 1959 titled
“There is plenty of room at the bottom”.
While many definitions of nanotechnology exist, the one most widely used is from the
US Government’s National Nanotechnology Initiative (NNI). According to the NNI,
nanotechnology is defined as:
“Research and technology development at the atomic, molecular and macromolecular
levels in the length scale of approximately 1 — 100 nanometer range, to provide a
fundamental understanding of phenomena and materials at the nanoscale and to create
and use structures, devices and systems that have novel properties and functions because
of their small and/or intermediate size.”
More simply put, nanotechnology is the space at the nanoscale (i.e. one billionth of a
meter), which is smaller than “micro” (one millionth of a meter) and larger than
“pico”(one trillionth of a meter). Nanoparticles 1— 100 nm. In comparison,
representative structures and materials found in nature are typically referenced to have
the following dimensions:
Atom 0.1 nm
DNA (width) 2 nm
Protein 5—50 nm
Virus 75—100 nm
Materials internalized by cells 100 nm
Bacteria 1,000—10,000 nm
White Blood Cell 10,000 nm
The size domains of components involved with nanotechnology are similar to that of
biological structures. For example, a quantum dot is about the same size as a small
protein (<="" molecules).="" wound-healing="" and="" cells="" white-blood="" (e.g.=""
nanostructures="" biological="" as="" just="" damages="" lesions="" repair="" sense=""
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4. NANOMEDICINE
The emerging teld of medical nanorohorics is aimed at overcoming this shortcomings.
The medicine and nanorohorics polls within the purview of nanotechnologies. Our bodies
are filled with intricate, active molecular structures. Where those structures are managed,
health suffers. Modern medicine can affect the works of the body in many ways, but from
a molecular viewpoint it remains crude incurred. Molecular manufacturing can construct
a range of medical instruments and devices with fat greater abilities. The body is an
enormously coming in world of molecules.
To understand what nanotechnology can do for medicine, we need a picture of the body
from a molecular perspective. The human body can be seen as a workyard, construction
site, and battleground form molecular machines. It works remarkably well, using systems
so complex that medical science still doesn’t understand many of them. Failures, though,
are all too common.
Many of the cells are very tiny, but they are very active; they manufacture various
substances; they walk around; they wiggle; they fight infection; pump blood and they do
all kings of marvelous things- all on a very small scale. They also store information
•Nanorobotswould constitute any “smart”structure capable of actuation, sensing,
signaling, information processing, intelligence, manipulation and swarm behaviorat nano
scale (10-9m).
•Bio nanorobots–Nanorobots designed (and inspired) by harnessing properties of
biological materials (peptides, DNAs), their designs and functionalities. These are
inspired not only by nature but machines too.
•Nanorobots could propose solutions at most of the
BIOMEDICAL APPILICATIONS OF NANOROBOTICS
The enormous potential in the biomedical capabilities of nanorobots and the imprecision
and side effects of medical treatments today make nanorobots very desirable. Medical
treatment today involves the use of surgery and drug therapy. Surgery is a direct, manual
approach to fixing the body. However, no matter how highly trained the specialists may
be, surgery can still be dangerous since anesthetics, infections, organ rejection, and
missed cancer cells can all cause failure. Surgeons lack fine-scale control. From the
perspective of a cell, a fine surgical scalpel is as crude as a blunt tool. Invasive surgery
wounds peripheral tissue and causes unnecessary harm to the patient
Drug therapy affects the body at the molecular level. Drug molecules are dumped into the
body where they are transported by the circulatory system. They may come into contact
with un-targeted parts of the body and lead to unwanted side effects. Nanomedical robots,
however, will have no difficulty identifying cancer cells and will ultimately be able to
track them down and destroy them wherever they ma~ be growing. This is why the
medical profession is looking towards the use of biomedical, nanotechnological
engineering to refine the treatment of diseases.
PROPERTIES OF NANOMEDICAL ROBOTS
Nanorobots will typically be .5 to 3 microns large with 1-100 nm parts. Three microns is
the upper limit of any nanorobot because nanorobots of larger size will block capillary
flow. The nanorobot’s structure will have two spaces that will consist of an interior and

5. exterior. The exterior of the nanorobot will be subjected to the various chemical liquids in
our bodies but the interior of the nanorobot will be a closed, vacuum environment into
which liquids from the outside cannot normally enter unless it is needed for chemical
analysis. A nanorobot will prevent itself, from being attacked by the immune system by
having a passive, diamond exterior. The diamond exterior will have to be smooth and
flawless because past experiments have shown that this prevents Ieukocytes activities
since the exterior is chemically inert and have low bioactivity. Nanorobots will
communicate with the doctor by encoding messages to acoustic signals at carrier wave
frequencies of 1-100 MHz. When the doctor gives a command to the nanorobots, the
nanorobots can receive the message from the acoustic sensors on the nanorobots and
implement the doctor’s orders. Replication is a crucial basic capability for molecular
manufacturing. However, in the case of nanorobots, we should restrict manufacturing to
in vitro (in laboratory) replication. Replication in the body (in vivo) is dangerous because
it might go out of control. If even replicating bacteria can give humans so many diseases,
the thought of replicating nanorobots can present unimaginable dangers to the human
body. When the nanorobots are finished with their jobs, they will be disposed from the
body to prevent them from breaking down and malfunctioning.
PRINCIPAL NANOROBOTIC APPLICATIONS
The availability of advanced nanomedical instrumentalities should not significantly alter
the classical medical treatment methodology, although the patient experiences and
outcomes will be greatly improved. Treatment in the nanomedical era will become faster
and more accurate, efficient and effective.
A. DRUG DELIVERY
Nanotechnology provides a wide range of new technologies for developing customized
solutions that optimize the delivery of pharmaceutical products.
To be therapeutically effective, drugs need to be protected during their transit to the target
action site in the body while maintaining their biological and chemicals properties. Some
drugs are highly toxic and can cause harsh side effects and reduced therapeutic effect if
they decompose during their delivery. Depending on where the drugs will be absorbed
(i.e. colon, small intestine, etc), and whether certain natural defense mechanisms need to
be passed through such as the blood-brain barrier, the transit time and delivery challenges
can be greatly different. Once a drug an-ives at its destination, it needs to be released at
an appropriate rate for it to be effective. If the drug is released too rapidly it might not be
completely absorbed, or it might cause gastro-intestinal irritation and other side effects.
The drug delivery system must positively impact the rate of absorption, distribution,
metabolism, and excretion of the drug or other substances in the body. In addition, the
drug delivery system must allow the drug to bind to its target receptor and influence that
receptor’s signalling and action, as well as other drugs, which might also be active in the
body.
Drug delivery systems also have severe restrictions on the materials and production
processes that can be used. The drug delivery material must be compatible and bind
easily with the drug, and be bioresorbable (i.e. degrade intofragments after use which are
either metabolized or eliminated via normal excretory routes). The production process
must respect stringent conditions on processing and chemistry that won’t degrade the

6. drug, and still provide a cost effective product.
Nanotechnology can offer new drug delivery solutions in the following areas.
1. Drug Encapsulation
One major class of drug delivery systems is materials that encapsulate drugs to protect
them during transit in the body. Drug encapsulation materials include liposomes and
polymers (i.e. Polylactide (PLA) and Lactide-co-Glycolide (PLGA)) which are used as
microscale particles. The materials form capsules around the drugs and permit timed drug
release to occur as the drug diffuses through the encapsulation material. The drugs can
also be released as the encapsulation material degrades or erodes in the body.
Nanoparticle encapsulation is also being investigated for the treatment of neurological
disorders to deliver therapeutic molecules directly to the central nervous system beyond
the blood-brain barrier, and to the eye beyond the blood-retina barrier. Applications could
include Parkinson’s, Huntington’s, Alzheimer’s, ALS and diseases of the eye.
2. Functional Drug Carriers
Another class of drug delivery systems where nanotechnology offers interesting solutions
is in the area of nanomaterjals that carry drugs to their destination sites and also have
functional properties. Certain nanostrucfures can be controlled to link with a drug, a
targeting molecule, and an imaging agent, then attract specific cells and release their
payload when required.
B. DRUG DISCOVERY
Nano and micro technologies are part of the latest advanced solutions and new paradigms
for decreasing the discovery and development times for new drugs, and potentially
reducing the development costs. Traditional trial-anderror methods have contributed to a
discovery process lasting 10 years or more for new drugs to reach the market. In recent
years, a number of new and complementary technologies have been developed which
considerably impact the drug discovery process.
High-throughput arrays and ultra-sensitive labeling and detection technologies are being
used to increase the speed and accuracy of identifying genes and genetic materials for
drug discovery and development. These micro and nano technologies along with
information technology solutions such as combinatorial chemistry, computational
biology, computer-aided drug design, data mining, and data processing tools are
addressing the challenges related to eliminating critical bottlenecks in drug discovery
replacement. While most types of tissues repair the interaction of stem cells with
chemical modulators, there are differences in the ways that various tissues heal.
“Hard” tissues such as bone and teeth heal by reproducing tissues indistinguishable from
the original. However in cases where a dental or artificial bone implant is required, the
structural material used in the implant may trigger immune rejection, corrode in the body
fluids, or no longer bond to the host bone. This can require additional surgery or result in
the loss of the implant’s function. In many cases, the failure occurs at the tissue-implant
interface, which may be due to the implant material weakening its bond with the natural
material.

7. To overcome this, implants are often coated with a biocompatible material to increase
their adherence properties and produce a greater surface area to volume ratio for the
highest possible contact area between the implant and natural tissue. “Soft” tissues such
as skin, muscle, nerves, blood vessels and ligaments repair damaged areas with fibrous
tissue. Damaged tissue from various sources such as burns and ulcers can be self-repaired
by the body, but can also result in scar formation. Graft material using artificial sheets
can replace skin and other tissue with reasonable graft stability and cosmetic outcome.
Nanotechnology can new offer new solutions for tissue repair and replacement in the
following’ areas.
. IMPLANTABLE DEVICS
Nanotechnology offers sensing technologies that provide more accurate and timely
medical information for diagnosing disease, and miniature devices that can administer
treatment automatically if’ required. Health assessment can require medical professionals,
invasive procedures and extensive laboratory testing to collect data and diagnose disease.
This process can take hours, days or weeks for scheduling and obtaining results. Some
medical information is extremely time sensitive such as finding out if there is sufficient
blood flow to an organ or tissue after transplant or reconstructive surgery, before
irreversible damage occurs.
Certain medical tests such as biopsies are subjective and can provide inconclusive or
incorrect results. In a false negative result where a needle misses the tumor and then
samples a normal tissue, the cancer nay go untreated and can impact a patient’s chances
for long-term survival.
Some tests such as diabetes blood sugar levels require patients to administer the test
themselves to avoid the risk of their blood glucose falling to dangerous levels. Certain
users such as children and the elderly may not be able to perform the test properly, timely
or without considerable pain.
People who are exposed to radiation or hazardous chemicals in their work environment
are at a higher risk of illness. Occasional testing is typically done but may not detect a
disease in its early stage. Early detection could initiate timely treatment with a higher
chance of success, and have a worker removed from the hazardous environment to
prevent further damage.
Nanotechnology can new offer new implantable and/or wearable sensing technologies
that provide continuous and extremely accurate medical information. Complementary
microprocessors and miniature devices can be incorporated with sensors to diagnose
disease, transmit information and administer treatment automatically if required.
Example applications are as follows.
I Retina Implants
Retinal implants are in development to restore vision by electrically stimulating
functional neurons in the retina One approach being developed by various groups
including a project at Argonne National Laboratory is an artificial retina implanted in the
back of the retina. The artificial retina uses a miniature video camera.
2 Cochlear Implants

8. A new generation of smaller and more powerful cochlear implants are intended to be
more precise and offer greater sound quality.
D. SURGICAL AIDS
1 Operating Tools
Medical devices that contain nano and micro technologies will allow surgeons to perform
familiar tasks with greater precision and safety, monitor physiological and biomechanical
parameters more accurately, and perform new tasks that are not currently done.
2 Surgical Robotics
Robotic surgical systems are being developed to provide surgeons with unprecedented
control over precision instruments. This is particularly useful for minimally invasive
surgery. Instead of manipulating surgical instruments, surgeons use their thumbs and
fingers to move joystick handles on a control console to maneuver two robot arms
containing miniature instruments that are inserted into ports in the patient. The surgeon’s
movements transform large motions on the remote controls into micro-movements on the
robot arms to greatly improve mechanical precision and safety.
E DIAGNOSTIC TOOLS
1 Genetic Testing
Nano and micro technologies provide new solutions for increasing the speed and
accuracy of identifying genes and genetic materials for drug discovery and development,
and for treatment-lnked disease diagnostics products.
dyes are not always precise or sufficiently sensitive
3Ultra-sensitive Labeling and Detection Technologies
Several new technologies are being developed to improve the ability to label and detect
unknown target genes. At Genicon, gold nanoparticle probes are being treated with
chemicals that cling to target genetic materials and illuminate when the sample is exposed
to light.
Killing cancer cells.
The device would circulate freely throughout the body, and would periodically sample its
environment by determining whether the binding sites were or were not occupied.
Occupancy statistics would allow determination of concentration. Today’s monoclonal
antibodies are able to bind to only a single type of protein or other antigen, and have not
proven effective against most cancers. The cancer killing device suggested here could
incorporate a dozen different binding sites and so could monitor the concentrations of a
dozen different types of molecules. The computer could determine if the profile of
concentrations fit a pre-programmed “cancerous” profile and would, when a cancerous
profile was encountered, release the poison.
Beyond being able to determine the concentrations of different compounds, the cancer
killer could also determine local pressure.
By using several macroscopic acoustic signal sources, the cancer killer could determine
its location within the body much as a radio receiver on earth can use the transmissions
from several satellites to determine its position (as in the widely used GPS system). .

9. The cancer killer could thus determine that it was located in (say) the big toe. If the
objective was to kill a colon cancer, the cancer killer in the big toe would not release its
poison. Very precise control over location of the cancer killer’s activities could thus be
achieved. The cancer killer could readily be reprogrammed to attack different targets (and
could, in fact, be reprogrammed via acoustic signals transmitted while it was in the
body). This general architecture could provide a flexible method of destroying unwanted
structures (bacterial infestations, etc).
Providing oxygen
A second application would be to provide metabolic support in the event of impaired
circulation. Poor blood flow, caused by a variety of conditions, can result in serious tissue
damage. A major cause of tissue damage is inadequate oxygen. A simple method of
improving the levels of available oxygen despite reduced blood flow would be to provide
an “artificial red blood cell of about a day by about a liter of small spheres.
As oxygen is being absorbed by our artificial red blood cells in the lungs at the same time
that carbon dioxide is being released, and oxygen is being released in the tissues when
carbon dioxide is being absorbed, the energy needed to compress one gas can be provided
by decompressing the other. The power system need only make up for losses caused by
inefficiencies in this process. These losses could presumably be made small, thus albwing
our artificial red blood cells to operate with little energy consumption conditions of
temperature and pressure. Thus, our spheres are over 2,000 times more efficient per unit
volume than blood; taking into account that blood is only about half occupied by red
blood cells, our spheres are over 1,000 times more efficient than red blood cells.
Artificial mitochondria
While providing oxygen to healthy tissue should maintain metabolism, tissues already
suffering from ischemic injury (tissue injury caused by loss of blood flow) might no
longer be able to properly metabolize oxygen. In particular, the mitochondria will, at
some point, fail.
15
Increased oxygen levels in the presence of nonfunctional or partially functional
mitochondria will be ineffective in restoring the tissue. However, more direct metabolic
support could be provided. The direct release of ATP, coupled with selective release or
absorption of critical metabolifes (using the kind of selective transport system mentioned
earlier), should be effective in restoring cellular function even when mitochondrial
function had been compromised. The devices restoring metabolite levels, injected into the
body, should be able to operate autonomously for many hours ~depending on power
requirements, the storage capacity of the device and the release and uptake rates required
to maintain metabolite levels).
8. Further possibilities
While levels of critical metabolites could be restored, other damage caused during the
ischemic event would also have to be dealt with. In particular, there might have been
significant free radical. damage to various molecular structures within the cell, including
its DNA. If damage was significant restoring metabolite levels would be insufficient, by
itself, to restore the cell to a healthy state. Various options could be pursued at this point.

10. If the cellular condition was deteriorating (unchecked by the normal homeostatic
mechanisms, which presumably would cease to function when cellular energy levels fell
below a critical value), some general method of slowing further deterioration would be
desirable.
Cooling of the tissue, or the injection of compounds that would slow or block
deteriorative reactions would be desirable. As autonomous molecular machines with
externally provided power could be used to restore function, maintaining function in the
tissue itself would no longer be critical. Deliberately turning off the metabolism of the
cell to prevent further damage would become a feasible option. Following some interval
of reduced (or even absent) metabolic activity during which damage was repaired, tissue
metabolism could be restarted again in a controlled fashion.
It is clear that this approach should be able to reverse substantially greater damage than
can be dealt with today. A primary reason for this is that autonomous molecular machines
using externally provided power would be able to continue operating even when the
tissue itself was no longer functional. We would finally have an ability to heal injured
cells, instead of simply helping injured cells to heal themselves.
CONCLUSION
All of these current developments in technology directs humans a step closer to
nanorobots and simple, operating nanorobots is the near future. Nanorobots can
theoretically destroy all common diseases of the 2lstcenturythereby ending much of the
pain and suffering. It can also have (alternative, practical uses such as improved
mouthwash and cosmetic creams that can expand the commercial market in biomedical
engineering. People can envision a future where people can self-diagnose their ‘own
ailments with the help of nanorobot monitors in their bloodstream. Simple everyday
illnesses can be cured without ever visiting the physician. lnvasivesurgery will be
replaced by an operation carried out by nano-surgical robots. Although research into
nanorobots is in its preliminary stages, the promise of such technology is endless.