Nanotechnology is the science of engineering molecularly precise structures and, ultimately, molecular machines.
This technology is conducted at a nanoscale, which is about 1 to 100 nanometers. A nanometer is one-billionth of a meter,
the width of about five carbon atoms nestled side by side. Nanomedicine is a branch of nanotechnology and its ultimate tool
is the medical nanobot - a robot the size of a bacterium that can manipulate and control materials at an atomic and molecular level.
While some might consider the future of nanorobots as science fiction, scientists point out that each of us is alive today because of
countless biological nanobots operating within each of our trillions of cells. We call them ribosomes - sphere-shaped structures within
each cell that are essentially machines programmed with a function of reading messenger RNA and synthesizing specific proteins.
Medical nanorobotics holds a greatest promise for regenerative medicine and with diligent effort, the first fruits of medical nanorobotics
could begin to appear in clinical treatment as early as the 2020s .
Scientists envision two ways in which nanotechnology may be able to extend our lives. One is by helping to eradicate life-threatening diseases such as cancer, or heart diseases and the other is by repairing damage to our bodies at the cellular level .
Nowadays nanotechnology provides a wide range of possibilities for developing customized means to optimize the delivery of chemotherapy drugs. Harmful side effects of chemotherapy, such as immune suppression, liver or heart toxicity are commonly a result of drug delivery methods that don't reach their intended target cells accurately . In an attempt to overcome this challenge, researchers used one nanoparticle to deliver the chemotherapy drug and a nanobot to guide the drug carrier to the cancer tumor. Firstly, gold nanobots circulate through the bloodstream and exit where the blood vessels are leaking - at the site of cancer tumors. Once the nanobots accumulate at the tumor they are used to concentrate the heat from infrared light, heating up the tumor. Heat increases the level of a certain stress related protein on the surface of the tumor. The drug carrying nanoparticle is attached to amino acids that bind to this protein, so the increased level of protein at the tumor speeds up the accumulation of the chemotherapy drug-carrying nanoparticles at the tumor site .
Scientists at Georgia Tech and the Ovarian Cancer Institute (Atlanta, Georgia) have further developed a potential new treatment against cancer that uses magnetic nanoparticles to attach to cancer cells, removing them from the body, before they can establish new tumors. The treatment, tested in mice in 2008, has now been tested using samples from human cancer patients .
Recently, researchers at Durham University in the UK have used nanobots to drill into cancer cells, killing them in just 60 seconds. Magnetic arms propel the nanobots forward as a magnetic field controls their direction. The bots are able to swim in more viscous liquid than water, mimicking a variety of body fluids. They are now experimenting on micro-organisms and small fish, before moving on to rodents. Clinical trials in humans are expected to follow and it is hoped that the results may have the potential to save millions of lives .
Another major condition that we are confronted with and represents one of the biggest causes of morbidity and mortality worldwide, is heart disease. In this area, there are several efforts going on. A research team from Drexel University (Philadelphia, Pennsylvania) has developed a nanorobotic technology that is being considered for an important mission - drilling through clogged arteries and potentially curing atherosclerosis. This condition limits the ability of oxygen rich blood to reach vital organs and increases risk for heart attack or stroke. These nanobots are made up of tiny iron oxide beads, joined together in a chain. To induce movement through the blood stream, the chain is exposed to an external magnetic field. Scientists were able to control the speed, direction and size of the nano-chain based on the nature of the arterial occlusion. In 2016 the first tests were done on mice, and now the team will move on to testing in rabbits and pigs. They envision that if all goes as expected, by 2019 they'll be launching the bots into humans (via catheter injection). .
When it comes to nanotechnology, perhaps the most exciting possibility relies in the potential for repairing our bodies at the cellular level. Techniques for building nanorobots are currently being developed and scientists are confident that repairing of our cells will soon be possible. DNA in our cells becomes damaged with age, however nanorobots could be able to repair the damaged DNA and allow our cells to function correctly.
A nanorobot called a "chromallocyte" is currently being researched, as a possibility to extract all existing chromosomes from a diseased or deteriorated cell and insert fresh new ones in their place. This process is called chromosome replacement therapy. The replacement chromosomes are manufactured earlier, outside of the patient's body, using the patient's own individual genome as a blueprint. Each chromallocyte is loaded with a single copy of a digitally corrected chromosome set. After injection, each device travels to its target tissue cell and replaces old worn-out genes with new chromosome copies, then exits the cell and is removed from the body. Therefore, chromosome replacement therapy could be an attractive perspective to correct the accumulating genetic damage and mutations that lead to aging in every one of our cells .
In the future, nanomachine - based systems will be built, that are able to enter cells, sense differences from healthy ones and make modifications to the structure. The possibilities of these cell repair nanomachines are impressive. Moreover, scientists feel confident that cell repair machines could be programmed with more abilities with the help of artificial intelligence systems. Powerful nanocomputers will direct these bots to examine, take apart, and rebuild damaged molecular structures. Repair machines will not only be able to repair cells, but tissues as well. Fixing tissue by tissue, whole organs can be repaired. Finally, by fixing organ by organ, health is restored to the body .
Assuming that within a couple of decades, we will have nanobots in our blood stream that will keep us healthy at the cellular and molecular level, does not sound like a science fiction scenario anymore. These devices will be a billion times more powerful than they are today and will continue the accelerating path to radical life extension.
1. Nanotechnology and Radically Extended Life Span. http://www.lifeextension.com/magazine/2009/1/Nanotechnology-Radically-Extended-Life-Span/Page-01 (accessed on 31.10.2017).
2. Life Extension through Nanotechnology. http://www.understandingnano.com/life-extension-nanotechnology.html (accessed on 31.10.2017).
3. Bhowmik, D. (2009). Role of Nanotechnology in novel Drug Delivery system. Journal of Pharmaceutical Science and Technology, 1(1): 20-35.
4. Targeted Drug Delivery That Hits the Mark. http://www.understandingnano.com/nanomedicine-nanorod-targeted-drug-delivery.html (accessed on 31.10.2017).
5. Magnetic Nanoparticles Show Promise for Combating Human Cancer. http://www.understandingnano.com/cancer-treatment-magnetic-nanoparticles.html (accessed on 31.10.2017).
6. These tiny robots can kill cancer cells. https://www.weforum.org/agenda/2017/09/nanobots-kill-drill-cancer-cells-60-seconds (accessed on 31.10.2017).
7. Tiny Robots Can Clear Clogged Arteries. https://www.smithsonianmag.com/innovation/tiny-robots-can-clear-clogged-arteries-180955774 (accessed on 31.10.2017).
8. Senthilnathan, B., Bejoy, J., Suruthi, L., Valentina, P., Robertson, S. (2016). Nanorobots-A hypothetical concept of interest. Pharma Science Monitor, 7(3). http://www.pharmasm.com/pdf_files/20161015045315_20160725053934_08_senthilnathan.pdf.