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Nanorobots are nanodevices that will be used for the purpose of maintaining and protecting the human body against pathogens.
There is no technology for the treatment of AIDS. Some of the drugs of
specific composition are given to the patients depending on the intensity of
the disease. The drugs using nowadays are able to increase the lifetime to a
few years only. To make the treatment more specific, we use the nanodevices
that use nanosensors to sense the AIDS infected WBC’s. In this we are using
nanorobots to get back the HIV infected WBC’s. By doing so constant levels of
WBC’s are maintained in the blood stream.
In India more than 50
lakhs of people are infected by this dreaded disease and it constitutes 10% of
the total infected. We are doing research on this paper and we hope that this
theoretical approach can be made practical in the near future, so that the
killer disease AIDS could also be made in control on the hands of Human with
the emerging new technology like NANOTECHONOLOGY which has a Bi o-medical
Application.
INTRODUCTION
Nano is one billionth of one. Now we have the so NANOTECHNOLOGY called
microprocessors and microarray technology that would reach the nano level
within a few decades, we suppose. Some call this technology to be
nanotechnology and some others name it the molecular nanotechnology, to be
specific.
REASONS FOR APPLYING NANOTECH TO
BIOLOGICAL SYSTEMS
Most animal cells are 10,000 to 20,000
nanometers in diameter. This means that nanoscale devices (having at least one
dimension less than 100 nanometers) can enter cells and the organelles inside
them to interact with DNA and proteins. Tools developed through nanotechnology
may be able to detect disease in a very small amount of cells or tissue. They
may also be able to enter and monitor cells within a living body.
Miniaturization will allow the tools for many different tests to be situated
together on the same small device. This means that nanotechnology could make it
possible to run many diagnostic tests simultaneously with more sensitivity. In
general, nanotechnology may offer a faster and more efficient means for us to
do much of what we do now
NANOMEDICINE
The emerging field
of nanorobotics is aimed at overcoming the shortcomings present in the
traditional way of treatment of patients.
Our bodies are filled with intricate, active molecular structures. When
those structures are damaged, health suffers. Modern medicine can affect the
work of the body in many ways, but from a molecular viewpoint it remains crude.
Molecular manufacturing can construct a range of medical instruments and
devices with greater abilities. 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.
BIOMEDICAL APPILICATIONS OF
NANOROBOTS
The enormous
potential in the biomedical capabilities of nanorobots and the imprecision and
side effects of medical treatments today make nanorobots very desirable. But
today, in this revolutionary era we propose for nanomedical robots, since they
will have no difficulty in identifying the target site cells even at the very
early stages which cannot be done in the traditional treatment and will
ultimately be able to track them down and destroy them wherever they may be
growing. By having these Robots, we can refine the treatment of diseases by
using biomedical, nanotechnological engineering.
Nanorobot designed to perform cell surgery
WHAT IS A MEDICINAL
NANOROBOT ?
Nanorobots are
theoretical microscopic devices measured on the scale of nanometers (1 nm
equals one millionth of a millimeter). When fully realized from the
hypothetical stage, they would work at the atomic, molecular and cellular level
to perform tasks in both the medical and industrial fields that have therefore
been the stuff of science fiction .Nanomedicine’s nanorobots are so tiny that
they can easily traverse the human body. Scientists report the exterior of a
nanorobot will likely be constructed of carbon atoms in a diamondoid structure
because of its inert properties and strength. Super-smooth surfaces will lessen
the likelihood of triggering the body’s immune system, allowing the nanorobots
to go about their business unimpeded.
Glucose or natural body sugars and oxygen might be a source for
propulsion and the nanorobot will have other biochemical or molecular parts
depending on its task.
Nanorobot in Nano scale
According
to current theories, nanorobots will possess at least rudimentary two-way
communication; will respond to acoustic signals; and will be able to receive
power or even re-programming instructions from an external source via sound
waves. A network of special stationary nanorobots might be strategically
positioned throughout the body, logging each active nanorobot as it passes,
then reporting those results, allowing an interface to keep track of all of the
devices in the body.
A doctor could not only monitor a patient’s progress but change the instructions of the nanorobots in vivo to progress to another stage of healing. When the task is completed, the nanorobots would be flushed from the body.
A doctor could not only monitor a patient’s progress but change the instructions of the nanorobots in vivo to progress to another stage of healing. When the task is completed, the nanorobots would be flushed from the body.
Nanorobot performing operations on blood cells
Nanorobotic phagocytes called
microbivores could patrol the bloodstream, seeking out and digesting unwanted
pathogens including bacteria, viruses or fungi. Each nanorobot could completely destroy one
pathogen in just 30 seconds - about 100 times faster than natural leukocytes or
macrophages - releasing a harmless effluent of amino acids, mononucleotides,
fatty acids and sugars. No matter that a bacterium has acquired multiple drug
resistance to antibiotics or to any other traditional treatment. The
microbivore will eat it anyway, achieving complete clearance of even the most
severe septicemic infections in minutes to hours, as compared to weeks or even
months for antibiotic-assisted natural phagocytic defenses, without increasing
the risk of sepsis or septic shock. Related nanorobots could be programmed to
recognize and digest the cancer cells and to clear circulatory obstructions
within a minute in order to rescue stroke patients from ischemic damage.
More sophisticated medical nanorobots
will be able to intervene at the cellular level, performing surgery within
cells. Physician-controlled nanorobots could extract existing chromosomes from
a diseased cell and insert newly manufactured ones in their place, a process
called chromosome replacement therapy. This would allow a permanent cure of any
pre-existing genetic disease, and permit cancerous cells to be reprogrammed to
a healthy state.
IMPLEMENTATION
ANTI - HIV USING NANOTECHNOLOGY
AIDS
The virus responsible
for the condition known as AIDS (Acquired Immunodeficiency Syndrome), is named
HIV (Human Immunodeficiency Virus). AIDS is the condition whereby the body's
specific defense system against all infectious agents no longer functions
properly. There is a focused loss over time of immune cell function, which
allows intrusion by several different infectious agents, the result of which is
loss of the ability of the body to fight infection and the subsequent acquisition
of diseases such as pneumonia.
The immune system is a system within all vertebrates , which in general terms, is comprised of two important cell types namely B-cell and T-cell. B-cell is responsible for the production of antibodies (proteins which can bind to specific molecular shapes), and the T-cell (two types) is responsible either for helping the B-cell to make antibodies, or for the killing of damaged or "different" cells (all foreign cells except bacteria) within the body. The two main types of T-cells are the "helper-cell and the cytotoxic T-cell. The T-helper population is further divided into those which help B-cells (Th2) and those which help cytotoxic T-cells (Th1). Therefore, in order for a B-cell to do its job requires the biochemical help of Th2 helper T-cells; and, for a cytotoxic T-cell to be able to eliminate a damaged cell requires the biochemical help of a Th1 helper T-cell.
The immune system is a system within all vertebrates , which in general terms, is comprised of two important cell types namely B-cell and T-cell. B-cell is responsible for the production of antibodies (proteins which can bind to specific molecular shapes), and the T-cell (two types) is responsible either for helping the B-cell to make antibodies, or for the killing of damaged or "different" cells (all foreign cells except bacteria) within the body. The two main types of T-cells are the "helper-cell and the cytotoxic T-cell. The T-helper population is further divided into those which help B-cells (Th2) and those which help cytotoxic T-cells (Th1). Therefore, in order for a B-cell to do its job requires the biochemical help of Th2 helper T-cells; and, for a cytotoxic T-cell to be able to eliminate a damaged cell requires the biochemical help of a Th1 helper T-cell.
IMMUNESYSTEM
Whenever any
foreign substance or agent enters our body, the immune system is activated.
Both B- and T-cell members respond to the threat, which eventually results in
the elimination of the substance or agent from our bodies. If the agent is one
which goes inside one of our cells and remains there most of the time (intracellular
pathogens like viruses or certain bacteria which require the inside of one of
our cells in order to live), the "best" response is the activation of
cytotoxic T-cells (circulate in the bloodstream and lymph), which eliminate the
agent through killing of the cell which contains the agent (agent is otherwise
"hidden"). Both of these kinds of responses (B-cell or cytotoxic
T-cell) of course require specific helper T-cell biochemical information as
described above. Usually, both B-cell and cytotoxic T-cell responses occur
against intracellular agents which provides a two-pronged attack. Normally,
these actions are wonderfully protective of us. The effect of HIV on the immune
system is the result of a gradual (usually) elimination of the Th1 and Th2 helper
T-cell sub- populations.
OPERATION OF HIV
How HIV
specifically affects the Immune System?
Remember about the proteins, which are part of the envelope of HIV?
Well, one of these proteins, named gp 120, (a sugar-containing protein called a glycoprotein, of approximately (120,000 molecular weight), "recognizes" a protein on helper T-cells named CD4, and physically associates with it. The CD4 [Cluster of Differentiation Antigen No. 4] protein is a normal part of a helper (both Th1 and Th2) T-cell's membrane.
Remember about the proteins, which are part of the envelope of HIV?
Well, one of these proteins, named gp 120, (a sugar-containing protein called a glycoprotein, of approximately (120,000 molecular weight), "recognizes" a protein on helper T-cells named CD4, and physically associates with it. The CD4 [Cluster of Differentiation Antigen No. 4] protein is a normal part of a helper (both Th1 and Th2) T-cell's membrane.
1.
Method of infection of HIV
Thus, CD4 is a
specific receptor for HIV. This virus however, can also infect other cells
which include macrophages and certain other kinds of cells which can engulf
substances through a process known as phagocytosis. As a consequence of the
interaction with CD4 on helper T-cells, HIV specifically infects the very cells
necessary to activate both B-cell and cytotoxic T-cell immune responses.
Without helper T-cells, the body cannot make antibodies properly, nor can
infected cells containing HIV (an intracellular pathogen) be properly
eliminated. Consequently, the virus can multiply, kill the helper T-cell in
which it lives, infect adjacent helper T-cells, repeat the cycle and on, until eventually there is a
substantial loss of helper T-cells.
The fight between the virus and the immune system for supremacy is
continuous. Our body responds to this onslaught through production of more
T-cells, some of which mature to become helper T-cells. The virus eventually
infects these targets and eliminates them, too. More T-cells are produced,
these too become infected and are killed by the virus. This fight may continue
for up to ten years before the body eventually succumbs, apparently because of
the inability to any-longer produce T-cells. This loss of helper T-cells
finally results in the complete inability of our body to ward-off even the
weakest of organisms (all kinds of bacteria and viruses other than HIV) which
are normally not ever a problem to us. This acquired condition of
immunodeficiency is called, AIDS.
1. Structure
of AIDS virus
METHODOLOGY
AIDS by itself is not a
killer disease. The cause of AIDS is the HIV virus that is capable of
destroying the immune system. Thereby the host system is vulnerable to small
diseases which will turn into a fatal one but actually it is not a fatal
disease. The HIV virus attack the WBC’s by converting them into the HIV.
Thereby all the WBC’s are converted into HIV, so the immune system will fail.
This is the reason for the death of the patient. Our idea is to convert the
AIDS affected WBC’s back into the original form of the WBC by using a Nanorobot,
thereby the patient is made to have a constant amount of immune system.
Nanorobot performs the inverse process of the HIV.
CONVERSION RATE
The HIV convert the WBC
in a faster manner .So the conversion by the A-HIV Nanorobot should also be
very much faster than that of the HIV, so that a constant level of WBC’s are
maintained in the blood stream. Because of this ,an AIDS patient can defend
himself from various diseases .The conversion rate should be at least five
times greater than that of the HIV conversion rate.
BASIC EQUATION
The basic equation for
the conversion of the HIV infected WBC’s back to its original form is given
below. The host system is the WBC and is converted by the HIV into an infected
WBC. This is the reason for AIDS.
CREATION OF NANO DEVICES
The creation of the nano
devices can be done using any of the two techniques that are available. They
are
·
Top-down approach
·
Bottom-up approach
CHALLENGES FACED BY NANOROBOTS
While designing
nonorobots in nanoscale dimensions there should be a better understanding of
how matter behaves on this small scale. Matter behaves differently on the
nanoscale than it does at larger levels. So the behavior of the nanorobots must
be taken care so that the do not affect us both inside and outside the body.
Other challenges apply
specifically to the use of nanostructures within biological systems.
Nanostructures can be so small that the body may clear them too rapidly for
them to be effective in detection or imaging. Larger nanoparticles may
accumulate in vital organs, creating a toxicity problem. So we need to consider
these factors as they anticipate how nanostructures will behave in the human
body and attempt to create devices the body will accept.
DESIGN OF NANOROBOTS
The nanorobots that we describe
here will be floating freely inside the body exploring and detect the HIV
virus. So, while designing such a nanorobot for AIDS treatment, the main
factors that are to be considered are given below.
TECHNIQUE USED
We use the bottom-up approach,
which involves assembling structures atom-by-atom or molecule-by-molecule which
will be useful in manufacturing devices used in medicine.
SIZE
Nanorobots will typically be 0.5 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.
STRUCTURE
The nanorobot’s structure will
have two spaces that are
Interior
It will be a closed, vacuum
environment into which liquids from the outside cannot normally enter unless it
is needed for chemical analysis.
Exterior
It will be subjected to various
chemical liquids in our bodies.
CHEMICAL ELEMENTS
Carbon will
likely be the principal element comprising the bulk of a medical nanorobot,
probably in the form of diamond or diamondoid or fullerene nanocomposites
largely because of the tremendous strength and chemical inertness of diamond.
Many other light elements such as hydrogen, sulfur, oxygen, nitrogen, fluorine,
silicon, etc. may also be used.
ACQUIRING POWER
It could metabolize local glucose
and oxygen for energy. Another
possibility is externally supplied acoustic power, which is probably most appropriate in a clinical
setting. There are literally dozens of
useful power sources that are potentially available in the human body.
COMMUNICATON
Having nanorobots inside the body it
is very essential to know the actions done by it. There are many different ways
to do this. One of the simplest ways to send broadcast-type messages into the
body, to be received by nanorobots, is acoustic messaging. A device similar to
an ultrasound probe would encode
messages on acoustic carrier waves at frequencies between 1-10 MHz.
TRACKING
A
navigational network may be installed in the body, with stationkeeping
navigational elements providing high positional accuracy to all passing nanorobots that interrogate them, wanting to
know their location. Physical positions can be reported continuously using an
in vivo communications network.
STRUCTURE OF NANOROBOT
The nanorobot consists of three main
parts like the DNA sensor,CPU,RNA converter and the power system. The purpose
of DNA sensor is to identify the HIV infected cell. The RNA converter is used
to change the RNA of the HIV. The CPU controls all the activities .The power
system provides the necessary energy for the working of the nanorobot.
1.
COMPONENTS OF NANOROBOT
DNA SENSORS
The DNA
sensor is an cantilever type. In one arm the actual sample is placed and
in the second arm the sample from the WBC is placed. Even if the samples differ
by a single base ,it can be identified. The structure is given below.
Carbon nanotube network field-effect transistors (NTNFETs) that
function as selective detectors of DNA immobilization and hybridization.
NTNFETs with immobilized synthetic oligonucleotides have been shown
to specifically recognize target DNA sequences, including H63D
single-nucleotide polymorphism (SNP) discrimination in the HFE gene,
responsible for hereditary hemochromatosis. The electronic responses
of NTNFETs upon single-stranded DNA immobilization and subsequent
DNA hybridization events were confirmed by using
fluorescence-labeled oligonucleotides and then were further explored
for label-free DNA detection at picomolar to micromolar
concentrations
POWER SYSTEM
The
nanorobot uses the glucose molecules present in
the human body as the power source. The conversion of this glucose
molecule into the energy is accomplished by the energy converter, which
is an important part of the nanorobot.
REQIREMENTS OF THE NANOROBOT
- It should e very small so that
the blood capillary flow is not affected.
- It should not be affected by the WBC.
- It should be capable of sensing the HIV
infected WBC only and its action is restricted to the infected WBC only.
- It should make its operations in the RNA to
convert back to the original DNA of the WBC by suitably changing the bases
like the adenine, guanine.
- It should convert the infected WBC into the
original WBC in a very faster manner.
- It should be made of cheaper rates, so that
the patient can afford it easily.
OPERATION
The designed anti-HIV
nanorobots are injected into the blood stream. These nanorobots continues the
process of conversion in the bone marrow, blood and in the thymus glands where
the concentration the WBC‘s are more. This process takes pace till the normal
death of the patient.
CONCLUSION:
The paper is
just a theoretical justification. But the recent advancement in the field of
nanotechnology gives the hope of the effective use of this technology in
medical field. This paper starts by giving an introduction to nanorobots and
its importance as recognized by various other technocrats. This is the
beginning of nanoera and we could expect further improvements such as a
medicine to AIDS using nanotechnology .
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