NANOTECHNOLOGY (Nanorobots In CANCER Detection and Treatment) A DREAM COME TRUE
ABSTRACT HEALING THE BODY FROM THE INSIDE OUT CANCER -one of the most deadly disease which primarily starts at the cellular level.To be more specific they start at the molecular level.At this molecular level, even the finest scalpel is like a huge instrument designed more to rip and tear than to heal and cure.The traditional methods that are available today to detect and treat cancer damages many of the cells which are noncancerous and not harmful. The detection of cancer by the traditional methods that are available today do not discover the disease at the earlier stage.So, the medical field is in need of some well structured and well organized simple tool that can detect and treat cancer efficiently and earlier.For the sake of this we present an idea for NANOROBOTS for detecting and treating cancerous cells at a very ealier stage.To design the nanorobots we use the NANOTECHNOLOGY, which is normally called as the molecular engineering.We also present the ways and means for curing the disease efficiently and without giving much pain to the patient.In our paper we discuss about the various features that a nanorobot should possess-down from the size up to the detection and treatment.
TABLE OF CONTENTS: Introduction Reasons for applying nanotechnology to biological systems Improving Cancer Treatment Nanomedicine Biomedical applications of nanorobotics – Nanotechnologies in patient care Nanotechnology as a link between Detection,Diagonosis and Treatment Creation of Nanodevices Design of Nanorobots Technique Used Size Structure Chemical Elements Ability to defend from the immune system Acquiring power Communication Tracking Exploration and detection of cancerous cells Treating and destroying cancerous cells Retrieval from body
INTRODUCTION: The image given in the frontpage is not from a comic book. It is the future of medicine. While examining the roots of nanorobotics and nanotechnology, we find it’s possibility was first proposed by Nobel prize winner Richard Feynman in his talk “There is plenty of room at the bottom”. 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.” Nanotechnology is also known as molecular nanotechnology or molecular manufacturing. 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). 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. REASONS FOR APPLYING NANOTECHNOLOGY TO BIOLOGICAL SYSTEMS:
5 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 as well as with more sensitivity. In general, nanotechnology may offer a faster and more efficient means for us to do much of what we do now. IMPROVING CANCER TREATMENT: Nanotechnology may also be useful for developing ways to eradicate cancer cells without harming healthy, neighboring cells.We can use nanotechnology to create therapeutic agents that are target specific to cancer cells and deliver their toxin in a controlled, timereleased manner.
NANOMEDICINE: The emerging field of nanorobotics is aimed at overcoming the shortcomings present in the traditional way of treatment of patients. The medicine and nanorobotics polls within the purview of nanotechnologies. 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 NANOROBOTICS – NANOTECHNOLOGIES IN PATIENT CARE: The enormous potential in the biomedical capabilities of nanorobots and the imprecision and side effects of medical treatments today make nanorobots very desirable. Traditional medical treatment for cancer involves Surgery Drug Therapy SURGERY: Surgery is a direct, manual approach to fixing the body.Surgery is dangerous since anesthetics, infections, organ rejection and missed cancer cells can all cause failure. DRUG THERAPY:
7 It 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. But today,in this revolutionary era we propose for NANOMEDICAL ROBOTS, since they will have no difficulty identifying cancer 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.
NANODEVICES AS A LINK BETWEEN DETECTION,DIAGNOSIS AND TREATMENT: We aim eventually to create nanodevices that do much more than deliver
8 treatment. The goal is to create a single nanodevice that will do many things: assist in imaging inside the body, recognize precancerous or cancerous cells, release a drug that targets only those cells, and report back on the effectiveness of the treatment.
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 behaviour 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
9 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 cancerous cells. So,while designing such a nanorobot for cancer detection and cancer treatment, the main factors that are to be considered are Technique used Size Structure Chemical elements Ability to defend from the immune system Acquiring power Communication Tracking Exploration and Detection of cancerous cells Treating and destroying cancerous cells Retrieval from body. 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 .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 will consist of 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 the 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/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.
ABILITY TO DEFEND FROM IMMUNE SYSTEM: Immune system response is primarily a reaction to a "foreign" surface.. Passive diamond exteriors may turn out to be ideal. Several experimental studies hint that the smoother and more flawless the diamond surface, the less leukocyte
11 activity and the less fibrinogen adsorption we will get. So it seems reasonable to hope that when diamond coatings can be laid down with almost flawless atomic precision, making nanorobot exterior surfaces with near-nanometer smoothness, that these surfaces may have very low bioactivity. Due to the extremely high surface energy of the passivated diamond surface and the strong hydrophobicity of the diamond surface, the diamond exterior is almost completely chemically inert and so opsonization should be minimized. If flawless diamond surfaces alone do not prove fully bioinactive as hoped, active surface management of the nanorobot exterior can be used to ensure complete nanodevice biocompatibility. Allergic and shock reactions are similarly easily avoided. 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.Thus the supervising physician can easily send new commands or parameters to
12 nanorobots already at work inside the body. Each nanorobot has its own power supply, computer, and sensorium, thus can receive the physician's messages via acoustic sensors, then compute and implement the appropriate response. The other half of the process is getting messages back out of the body, from the working nanodevices out to the physician. This can also be done acoustically. However, onboard power requirements for micron-scale acoustic wave generators in water dictate a maximum practical transmission range of at most a few hundred microns for each individual nanorobot. Therefore it is convenient to establish an internal communications network that can collect local messages and pass them along to a central location, which the physician can then monitor using sensitive ultrasound detectors to receive the messages. 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. EXPLORATION AND DETECTION OF CANCEROUS CELLS: Each cell type has its own unique set of surface antigens. Other cell surface antigens indicate the health status of the cell, the parent organ type, the species of the animal, and even the identity of the individuala kind of biochemical Social Security Number.
13 We use the following tools in cancer detection.
CANTILEVERS: These tiny levers, which are anchored at one end, can be engineered to bind to molecules that represent some of the changes associated with cancer. They bind to altered DNA sequences or proteins that are present in certain types of cancer. When these molecules bind to the cantilevers, surface tension changes, causing the cantilevers to bend. By monitoring the bending of the cantilevers, we can tell whether cancer molecules are present.Thus cantilevers can be used to detect the cancer in earliest stages.
NANOPORES: It helps to detect errors in genes that may contribute to cancer. Nanopores allow DNA to pass through one strand at a time, will make DNA sequencing more efficient. As DNA passes through a nanopore,
14 the shape and electrical properties of each base or letter, on the strand are monitored. Because these properties are unique for each of the four bases that make up the genetic code, the passage of DNA through a nanopore can be used to decipher the encoded information, including errors in the code known to be associated with cancer.
NANOTUBES – MARKING MUTATIONS: Another nanodevice that will help identify DNA changes associated with cancer is the nanotube. Nanotubes are carbon rods about half the diameter of a molecule of DNA that not only can detect the presence of altered genes, but they helps us to pinpoint the exact location of those changes. To prepare DNA for nanotube analysis, it must be attached with a bulky molecule to regions of the DNA that are associated with cancer. They can design tags that seek out specific mutations in the DNA and bind
15 to them.
NANOTUBES – MAPPING MUTATIONS: Once the mutation has been tagged, a nanotube tip resembling the needle on a record player is used to trace the physical shape of DNA and pinpoint the mutated regions. The nanotube creates a map showing the shape of the DNA molecule, including the tags identifying important mutations. Since the location of mutations can influence the effects they have on a cell, these techniques will be important in predicting disease.
QUANTUM DOTS – finding cancer signatures: Quantum dots are tiny crystals that glow when they are stimulated by ultraviolet light. The wavelength, or color, of the light depends on the size of the crystal. Latex beads filled with these crystals can be designed to bind to specific DNA sequences. By combining different sized quantum dots within a single bead, probes can be created that release distinct colors and intensities of light. When the crystals are stimulated by UV light, each bead emits light that serves as a sort of spectral bar code, identifying a particular region of DNA. To detect cancer, quantum dots can be designed to bind to sequences of DNA that are associated with the disease. When the quantum dots are stimulated with light, they emit their unique bar codes, or labels, making the critical, cancer-associated DNA sequences visible. The diversity of quantum dots allows us to create many unique labels, which can identify numerous regions of DNA simultaneously.
TREATING AND DESTROYING CANCEROUS CELLS: The nanorobot would have a small computer, several binding sites to determine the concentration of specific molecules, and a supply of some poison which could be selectively released and was able to kill a cell identified as cancerous.Some of the tools used for this purpose are NANOSHELLS: We can link nanoshells to antibodies that recognize cancer cells. We can let these nanoshells to seek out their cancerous targets, then applying near-infrared light. In laboratory cultures, the heat generated by the light-absorbing nanoshells has successfully killed tumor cells while leaving neighboring cells intact.
DENDRIMERS: Dendrimers are man-made molecules about the size of an average protein, and have a branching shape. This shape gives them vast amounts of surface area to which scientists can attach therapeutic agents or other biologically active molecules.
19 RETRIEVAL FROM BODY: Nanorobots will be able to exfuse themselves from the body via the usual human excretory channels; others will be designed to allow ready exfusion by medical personnel using apheresis-like processes (commonly called anapheresis) or active scavenger systems. It is very design dependent. CONCLUSION: All of the above techniques described above directs humans a step closer to nanorobots and simple, operating nanorobots is the near future. Nanorobots can efficiently treat and cure all deadly cancer of the 2lstcentury thereby ending much of the pain and suffering. Invasive surgery will be replaced by an operation carried out by nanosurgical robots. Thus the role of engineering and nanorobots in the biomedical field will be endless.
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