02-04-2010, 08:33 PM
AN ERA FOR NANO TECHNOLOGY
PRESENTED BY
K.ABBAS P.VENGADESHBABU
SECOND YEAR
DEPARTMENT OF ELECTRICAL & ELECTRONICS ENGINEERING
Abstract:
A new era on medicine are expected to happen in the coming years. Due to the
advances in the field of nanotechnology, nanodevice manufacturing has been
growing gradually. From such achievements in nanotechnology, and recent results
in biotechnology and genetics, the first operating biological nanorobots are
expected to appear in the coming 5 years, and more complex diamondoid based
nanorobots will become available in about 10 years. In terms of time it means a
very near better future with significant improvements in medicine. In this work
we present a practical approach taken on developing nanorobots for medicine in
the sense of using computational nanomechatronics techniques as ancillary tools
for investigating manufacturing design, nanosystems integration, sensing and
actuation for medicine applications. Thus the work describes pathways that could
Enable design testability, but also help scientists and profit corporations in
providing the helpful information needed to test and design integrated devises
and solutions towards manufacturing biomedical nanorobots.
What is nanotechnology?
Nanotechnology is the science of the extremely tiny. It involves the study and use of materials on an unimaginably small scale. Nano refers to a nanometre (nm). One nanometre is a millionth of a millimetre or about one eighty thousandth the width of a human hair.
Nanotechnology describes many diverse technologies and tools, which dont always appear to have much in common! Therefore it is better to talk about nanotechnologies, in the plural.
One thing that all nanotechnologies share is the tiny dimensions that they operate on. They exploit the fact that, at this scale, materials can behave very differently from when they are in larger form. Nanomaterials can be stronger or lighter, or conduct heat or electricity in a different way. They can even change colour; particles of gold can appear red, blue or gold, depending on their size.
These special attributes are already being used in a number of ways, such as in making computer chips, CDs and mobile phones. But researchers are progressively finding out more about the nanoscale world and aim to use nanotechnologies to create new devices that are faster, lighter, stronger or more efficient.
How are nanomaterials made?
Nanomaterials can be natural or manmade. For example, nanoparticles are produced naturally by plants, algae and volcanic activity. They have also been created for thousands of years as products of cooking and burning, and more recently from vehicle exhausts. Some proteins in the body, which control things like flexing muscles and repairing cells, are nanosized. We can set out to make nanomaterials in a variety of different ways. Some nanomaterials can assemble themselves from their components. Carbon fragments, for example, can self-assemble into nanotubes in this way. Another approach, used in the production of computer chips, is to etch nanomaterials from larger pieces of material. Increasingly, these two methods are converging, leading to exciting new production techniques. Now the applications of nanotechnology in medical field can be viewed:
Nanotechnology in medicine:
Ask a biochemist or microbiologist about the brave new world of nanotechnology and they will probably tell you that they have been working in it for decades.After all, typical biological molecules are significantly less than 100 nanometers (nm) long. But the problem with conventional biochemistry and microbiology is that you can rarely, if ever, get on a one-to-one basis with your molecules. Nanotechnology is changing that.We can now make functional structures so small that they can go and seek out individual molecules. Nanotechnology will enable us to measure or image concentrations of biological material that are equivalent to a grain of salt dissolved in an Olympic swimming pool.That has important implications for new therapies as well.logy in medicine.
The design of artificial environments that interact rationally with cells can lead to strategies in regenerative medicine that could expand human longevity and quality of life. This opportunity is exciting because it will push interdisciplinary science to its limits bringing together physical sciences, life sciences, engineering, and medicine toward a goal of enormous impact to society. The targets may include a cure for brain disorders such as Parkinson's and Alzheimer's disease, regeneration of heart tissue, a cure for diabetes, the regeneration of cartilage in adulthood, among many others. We have developed at Northwestern nanostructures that deliver regenerative signals to specific cells including neurons, bone cells, and endothelial cells involved in blood vessel formation. This lecture will describe the use of these systems in spinal cord injury to avoid paralysis, the repair of the heart after infarct, wound healing, and the repair of bone defects.
Exploring Nanotechnology in Cancer:
Nanotechnology offers the unprecedented and paradigm-changing opportunity to study and interact with normal and cancer cells in real time, at the molecular and cellular scales, and during the earliest stages of the cancer process. Through the concerted development of nanoscale devices or devices with nanoscale materials and components, the NCI Alliance for Nanotechnology in Cancer will facilitate their integration within the existing cancer research infrastructure. The Alliance will bring enabling technologies for:
Imaging agents and diagnostics that will allow clinicians to detect cancer in its earliest stages .
Systems that will provide real-time assessments of therapeutic and surgical efficacy for accelerating clinical translation .
Multifunctional, targeted devices capable of bypassing biological barriers to deliver multiple therapeutic agents directly to cancer cells and those tissues in the microenvironment that play a critical role in the growth and metastasis of cancer.
Agents that can monitor predictive molecular changes and prevent precancerous cells from becoming malignant.
Novel methods to manage the symptoms of cancer that adversely impact quality of life.
Research tools that will enable rapid identification of new targets for clinical development and predict drug resistance.
Nantechnology as a Cancer Fighter
To help get the most potent anti-cancer drugs off the shelf and into the clinic, University of Michigan researchers are using two nanotechnology approaches to precisely deliver drugs and visualize individual cells.
One system is a synthetic molecule called a dendrimer, and the other is a tiny plastic bead called a pebble.A dendrimer is a star-shaped synthetic molecule that can be as small as three or four nanometers in diameter, about the size of a single molecule of hemoglobin in a red blood cell. That means it is fine enough to slip through the walls of blood vessels and get inside cells.
Injected into the bloodstream, dendrimers converge on cancer cells, then enter the cells. There, they deliver the drugs that kill cancer cells. In preliminary animal studies, drugs appear to be 50 to 100 times more effective with this sort of direct delivery,
Why Nanotechnology in Cancer?
Nanoscale devices are somewhere from one hundred to ten thousand times smaller than human cells. They are similar in size to large biological molecules ("biomolecules") such as enzymes and receptors. As an example, hemoglobin, the molecule that carries oxygen in red blood cells, is approximately 5 nanometers in diameter. Nanoscale devices smaller than 50 nanometers can easily enter most cells, while those smaller than 20 nanometers can move out of blood vessels as they circulate through the body.
Because of their small size, nanoscale devices can readily interact with biomolecules on both the surface of cells and inside of cells. By gaining access to so many areas of the body, they have the potential to detect disease and deliver treatment in ways unimagined before now. And since biological processes, including events that lead to cancer, occur at the nanoscale at and inside cells, nanotechnology offers a wealth of tools that are providing cancer researchers with new and innovative ways to diagnose and treat cancer.
Nanotechnology and Diagnostics
Nanodevices can provide rapid and sensitive detection of cancer-related molecules by enabling scientists to detect molecular changes even when they occur only in a small percentage of cells.
Nanotechnology and Cancer Therapy
Nanoscale devices have the potential to radically change cancer therapy for the better and to dramatically increase the number of highly effective therapeutic agents. Nanoscale constructs can serve as customizable, targeted drug delivery vehicles capable of ferrying large doses of chemotherapeutic agents or therapeutic genes into malignant cells while sparing healthy cells, greatly reducing or eliminating the often unpalatable side effects that accompany many current cancer therapies.
Disease and ill health are caused largely by damage at the molecular and cellular level. Today's surgical tools are, at this scale, large and crude. From the viewpoint of a cell, even a fine scalpel is a blunt instrument more suited to tear and injure than heal and cure. Modern surgery works only because cells have a remarkable ability to regroup, bury their dead and heal over the injury.
Nanotechnology, "the manufacturing technology of the 21st century," should let us economically build a broad range of complex molecular machines (including, not incidentally, molecular computers). It will let us build fleets of computer controlled molecular tools much smaller than a human cell and built with the accuracy and precision of drug molecules. Such tools will let medicine, for the first time, intervene in a sophisticated and controlled way at the cellular and molecular level. They could remove obstructions in the circulatory system, kill cancer cells, or take over the function of subcellular organelles. Just as today we have the artifical heart, so in the future we could have the artificial mitochondrion.
Owing to the nascent stage of development of nanotechnology and the discordant development in the associated disciplines, many of these applications are in the exploratory stage, years away from practical use. It appears, however, that microelectronics and biotechnology represent two areas in which research results from nanotechnology can be immediately relevant.
Nanotechnology applied to therapeutic medicine remains distant. Some people even argue that the idea of nanorobots coursing through the bloodstream to repair damage resulting from blood clots and cancer belongs in the realm of science fiction and will remain so. In reality, nanobiotechnology, the convergence of nanotechnology and biotechnology, has already given rise to real practical application in the form of research and diagnostic tools. Companies in the United States such as Quantum Dot Corp, Nanosphere Inc and Molecular Nanosystems Inc are shipping or are close to shipping real products for research and diagnostic use.
Nanobiotechnology offers the potential of obtaining the most information from the smallest number of test samples in the shortest time at the lowest possible cost. Nanomaterials are so small that when they interact with biomolecules they generate detectable signals in the form of light emissions, a deflection of a nanoscale cantilever beam or magnetic field.
Currently over 200 molecular diagnostic tests for biomolecules have become associated with various disease states. Detection of these biomarkers offers the potential for therapeutic decision, monitoring the progression of disease, early diagnosis, risk assessment of predispositions to certain diseases and consequent preventive care.
Nano-tech is the next step after miniaturization. Cell phones are miniaturized versions of traditional landline phones. Wristwatches are miniature versions of clocks. Desktop computers are miniature versions of the original analog calculating machines. Miniaturization is commonplace in today's world. In tomorrow's world, nano-tech will be the new common technology. It will affect everyone on the planet, and may change civilization as it is now known.
Just imagine, changing atoms to behave a certain ways. You could make tiny microscopic nanomachines called swarms. One type of swarm could be the size of bacteria, and would be sent into the body to attack diseases. Some could be used to slow or suspend the human metabolism. This would allow time for a cure for a disease to be found. In space, astronauts could have their metabolism slowed or suspended while they travel on long journeys, so they don't age as fast.
Swarms could also do dirty, dangerous jobs that people don't like to do. A machine designed from this technology could be sent to change the atoms of an oil spill that would make it harmless. They could also be used to help treat sewage in waste treatment plants.
Nanoengineers in Singapore have invented a contact lens that can release precise amounts of medication to treat glaucoma and other eye diseases.
Developed by researchers at the Government-backed Institute of Bioengineering and Nanotechnology, the new technique for making lenses begins by mixing the drug with a pre-polymer liquid. This mix is then polymerised, creating a transparent contact lens material.
If the drug is water-soluble, it becomes trapped within a matrix of tiny interconnected, water-filled channels in the material. If it's water-insoluble, the drug is trapped within nano-spaces in the polymer network, and slowly leaches out into the channels. When the lens is in place, the contact with the fluid on the eyeball causes these channels to open up and slowly release the drug.
By adapting the water content of the original mix, the team can vary the size of the channels and so control the rate at which the drug is released.
The polymeric nanostructure allows the lenses to be permeable to gases (such as oxygen), salts, nutrients, water and other substances found in eye fluid.
Moreover, with changes to the size, concentration and structure of the polymeric nanoparticles within the lenses, the delivery system can be tailored to dispense various drugs or even produce self-lubricating contact lenses for those with dry eyes.
Most ophthalmic medications are currently delivered through eye drops. The problem with this method is that the drugs often mix with tears and can reach other organs through the bloodstream, potentially causing side effects.
What does the future hold?
It is difficult to predict the precise timescale at which different nanotechnologies will become a reality. But it is likely that, in the future, nanotechnologies could impact on many areas of life.
In the short term, nanotechnologies could yield smaller, faster computers and sharper, more efficient electronic displays. Putting nanoparticles into paints could reduce their weight; used on aircraft, this would reduce the overall weight and lower fuel consumption. Nanoparticles could also help to keep the environment clean. Researchers are studying the ability of nanoparticles to transform hazardous chemicals found in soil and groundwater into harmless compounds.
Major applications in the medical area are likely to be longer-term. Nanoparticles could be used to deliver drugs to specific parts of the body. They could also be used to construct lightweight, long-lasting implants, such as heart valves and hip replacements. We may see the development of intelligent clothing that can monitor the wearers blood pressure and heart rate, and detect dangerous chemicals in the environment.
Other potential longer-term applications include nano-engineered membranes to create more energy-efficient water purification processes, longer-lasting lubricants and higher performance engines.
Conclusion:
The era of nano technology has begun which will lead to incredible advancements in every field especially in medicine
