There are two ways in which nanotechnology may be able to extend our lives. One is by helping to eradicate life-threatening diseases such as cancer, and the other is by repairing damage to our bodies at the cellular level--a nano version of the fountain of youth.
Our average lifespan has been increased over the last 100 years by reducing the impact of life-threatening diseases. For example, vaccines have virtually eliminated smallpox. The application of nanotechnology in healthcare is likely to reduce the number of deaths from conditions such as cancer and heart disease over the next decade or so. There are many research programs working on these techniques; a few are discussed here, and others are discussed in the Medicine and Cancer pages (find these through the navigation bar).
So, what type of nano work is being done in the way of eradicating cancer, one of the most serious of diseases on our planet?
An intriguing targeted chemotherapy method uses one nanoparticle to deliver a chemotherapy drug and a separate nanoparticle to guide the drug carrier to the cancer tumor. First gold nanorods circulating through the bloodstream exit where the blood vessels are leaking at the site of cancer tumors. Once the nanorods accumulate at the tumor they are used to concentrate the heat from infrared light, heating up the tumor. This heat increases the level of a stress related protein on the surface of the tumor. The drug carrying nanoparticle (a liposome) 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 liposome at the tumor. For more details read the article at this link.
Magnetic nanoparticles that attach to cancer cells in the blood stream may allow the cancer cells to be removed before they establish new tumors. For more details read the article at this link.
In addition to individual research programs like these by various universities and companies, the U.S. National Cancer Institute has formed a group called the Alliance for Nanotechnology in Cancer. The NCI Alliance for Nanotechnology in Cancer is catalyzing targeted discovery and development efforts that offer the greatest advances in the near term and beyond. They are also working to facilitate the process of handing off those advances to the private sector for commercial development. This alliance includes a Nanotechnology Characterization Lab as well as eight Centers of Cancer Nanotechnology Excellence.
Another major killer in our time is heart disease. In this area, there are several efforts going on.
Researchers at the University of Santa Barbara have developed a nanoparticle that can deliver drugs to plaque on the wall of arteries. They attach a protein called a peptide to a nanoparticle which then binds with the surface of plaque. Studies have verified that the peptide attaches the nanoparticle to plaque. The researchers plan to use these nanoparticles to deliver imaging particles and drugs to both diagnosis and treat the condition. For more info see the article at this link.
Researchers at MIT and Harvard Medical School have attached a different peptide to a drug-carrying nanoparticle. This peptide binds to a membrane that is exposed in damaged artery walls, allowing the nanoparticle to release a drug at the site of the damage. The drug helps prevent the growth of scar tissue that can clog arteries. For more about this, see the article at this link.
To help coordinate this type of research, the U.S. National Heart Lung and Blood Institute has established four Program of Excellence in Nanotechnology Centers to focus on diseases of the lung and cardiovascular system. For example the Program of Excellence in Nanotechnology (PEN) for the treatment of Vulnerable Plaque is a partnership of 25 scientists from The Burnham Institute, University of California Santa Barbara, and The Scripps Research Institute. The scientists are developing methods to detect, monitor, treat, and eliminate "vulnerable" plaque, the type of plaque most likely to cause heart attacks. For more information on the Program of Excellence Centers see this link .
Perhaps the most exciting possibility exists in the potential for repairing our bodies at the cellular level. Techniques for building nanorobots are being developed that should make the repair of our cells possible. For example, as we age, DNA in our cells is damaged by radiation or chemicals in our bodies. Nanorobots would be able to repair the damaged DNA and allow our cells to function correctly.
This ability to repair DNA and other defective components in our cells goes beyond keeping us healthy: it has the potential to restore our bodies to a more youthful condition. This concept is discussed in Eric Drexler's Engines of Creation. Drexler states:
"Aging is fundamentally no different from any other physical disorder; it is no magical effect of calendar dates on a mysterious life-force. Brittle bones, wrinkled skin, low enzyme activities, slow wound healing, poor memory, and the rest all result from damaged molecular machinery, chemical imbalances, and mis-arranged structures. By restoring all the cells and tissues of the body to a youthful structure, repair machines will restore youthful health. "
In this area, there are several approaches being explored.
The Nanofactory Collorabation is an international group of scientists developing the techniques for atomically precise manufacturing, which is essentially the process of building structures atom by atom. Once developed this technique can be used to build nanorobots that can perform cellular level surgery, such as replacing DNA that is damaged as we age. For more about this see the article at this link.
The Nanomedicine Center for Nucleoprotein Machines is using a different method to develop the ability to replace damaged DNA. They are studying protein-based biological machines (nanorobots) which can handle tasks such as DNA replication and repairing damage in our bodies. As they state on their website, "We hope to identify common principles that can be applied to the design of artificial nucleoprotein machines with novel specificities, facilitating the precise manipulation of DNA and RNA at the atomic level."
The Nanomedicine Center for Nucleoprotein Machines is actually part of a national network of eight Nanomedicine Development Centers established by the U.S. National Institute of Health. The Centers state that they will "expand knowledge of the basic science of nanostructures in living cells, will gain the capability to engineer biological nanostructures, and then will apply the knowledge, tools, and devices to focus on specific target diseases. The bold, exciting challenges of this program represent a unique approach to combine nanoscale science - understanding and manipulating cellular nanostructures – with specific medical therapies."
An online copy of volume one of the book Nanomedicine by Robert Freitas.
Chapter 7: "Engines of Healing" from the book Engines of Creation, The Coming Era of Nanotechnology by Eric Drexler
Nanotechnology Roadmap developed by the Foresight Institute to guide researchers working toward atomically precise manufacturing.
Compiled by Earl Boysen of Hawk's Perch Technical Writing, LLC and UnderstandingNano.com. You can find him on Google+.