Posts about nanotubes

High School Student Creates: Test That is Much More Accurate and 26,000 Times Cheaper Than Existing Pancreatic Cancer Tests

Seeing what these kids come up with is so refreshing after being so disappointed by the actions fo our leaders (politicians, business leaders, financiers, law enforcement [spying on citizens because they feel electronic privacy is fine to invade, taking away liberty…], health care in the USA [twice as expensive as elsewhere with no better results, 10 of millions without coverage]…). These kids make me feel hopeful, unfortunately the actions of the powerful leave me less hopeful.

Jack Andraka created a new paper based test for diagnosing pancreatic cancer that is 50% more accurate, 400 times more sensitive, and 26,000 times less expensive than existing methods. His method uses carbon nanotubes and can catch the disease in very early stages which is critical to treatment success. The test also covers other forms of cancer very effectively (he concentrated on the results for pancreatic cancer given the low survival rates for that cancer). Jack Andraka: “I actually love single-walled carbon nanotubes; they’re like the superheroes of material science.”

His results are great. Often initial results can be difficult to actually turn into such positive results in the real world. But this is a great step and it is great to see what young minds can do. The claims for how much better, cheaper etc. are wildly different in various places on the International Science and Engineering Fair (ISEF) site.

Jack Andraka was awarded $75,000 for his development of a new method to detect pancreatic cancer as the winner of the top prize at the Intel ISEF (I believe it is new this year to call the winner the Gordon E. Moore Award).

Related: 2009 Intel Science and Engineering Fair WebcastsIntel International Science and Engineering Fair 2007Intel Science Talent Search 2012 AwardeesGoogle Science Fair 2011 Projects

A Novel Paper Sensor for the Detection of Pancreatic Cancer by Jack Andraka
North County High School, Glen Burnie, MD

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NASA Biocapsules Deliver Medical Interventions Based Upon What They Detect in the Body

Very cool innovation from NASA. The biocapsule monitors the environment (the body it is in) and responds with medical help. Basically it is acting very much like your body, which does exactly that: monitors and then responds based on what is found.

The Miraculous NASA Breakthrough That Could Save Millions of Lives

The Biocapsules aren’t one-shot deals. Each capsule could be capable of delivering many metred doses over a period of years. There is no “shelf-life” to the Biocapsules. They are extremely resilient, and there is currently no known enzyme that can break down their nanostructures. And because the nanostructures are inert, they are extremely well-tolerated by the body. The capsules’ porous natures allow medication to pass through their walls, but the nanostructures are strong enough to keep the cells in one place. Once all of the cells are expended, the Biocapsule stays in the body, stable and unnoticed, until it is eventually removed by a doctor back on Earth.

Dr. Loftus [NASA] thinks we could realistically see wildspread usage on Earth within 10 to 15 years.

The cells don’t get released from the capsule. The cells inside the capsule secrete therapeutic molecules (proteins, peptides), and these agents exit the capsule by diffusion across the capsule wall.

NASA plans to use the biocapsules in space, but they also have very promising uses on earth. They can monitor a diabetes patient and if insulin is needed, deliver it. No need for the person to remember, or give themselves a shot of insulin. The biocapsule act just like out bodies do, responding to needs without us consciously having to think about it. They can also be used to provide high dose chemotherapy directly to the tumor site (thus decreasing the side effects and increasing the dosage delivered to the target location. Biocapsules could also respond to severe allergic reaction and deliver epinephrine (which many people know have to carry with them to try and survive an attack).

It would be great if this were to have widespread use 15 years from now. Sadly, these innovations tend to take far longer to get into productive use than we would hope. But not always, so here is hoping this innovation from NASA gets into ourselves soon.

Related: Using Bacteria to Carry Nanoparticles Into CellsNanoparticles With Scorpion Venom Slow Cancer SpreadSelf-Assembling Cubes Could Deliver MedicineNanoengineers Use Tiny Diamonds for Drug Delivery

Using a Virus to Improve Solar-cell Efficiency Over 30%

Solar and wind energy are making great strides, and are already contributing significantly to providing relatively clean energy.

Researchers at MIT have found a way to make significant improvements to the power-conversion efficiency of solar cells by enlisting the services of tiny viruses to perform detailed assembly work at the microscopic level.

In a solar cell, sunlight hits a light-harvesting material, causing it to release electrons that can be harnessed to produce an electric current. The research, is based on findings that carbon nanotubes — microscopic, hollow cylinders of pure carbon — can enhance the efficiency of electron collection from a solar cell’s surface.

Previous attempts to use the nanotubes, however, had been thwarted by two problems. First, the making of carbon nanotubes generally produces a mix of two types, some of which act as semiconductors (sometimes allowing an electric current to flow, sometimes not) or metals (which act like wires, allowing current to flow easily). The new research, for the first time, showed that the effects of these two types tend to be different, because the semiconducting nanotubes can enhance the performance of solar cells, but the metallic ones have the opposite effect. Second, nanotubes tend to clump together, which reduces their effectiveness.

And that’s where viruses come to the rescue. Graduate students Xiangnan Dang and Hyunjung Yi — working with Angela Belcher, the W. M. Keck Professor of Energy, and several other researchers — found that a genetically engineered version of a virus called M13, which normally infects bacteria, can be used to control the arrangement of the nanotubes on a surface, keeping the tubes separate so they can’t short out the circuits, and keeping the tubes apart so they don’t clump.

The system the researchers tested used a type of solar cell known as dye-sensitized solar cells, a lightweight and inexpensive type where the active layer is composed of titanium dioxide, rather than the silicon used in conventional solar cells. But the same technique could be applied to other types as well, including quantum-dot and organic solar cells, the researchers say. In their tests, adding the virus-built structures enhanced the power conversion efficiency to 10.6% from 8% — almost a one-third improvement.

Read the full press release

Related: Using Virus to Build BatteriesUsing Viruses to Construct ElectrodesUsing Bacteria to Carry Nanoparticles Into Cells

Using Virus to Build Batteries

MIT researchers have shown they can genetically engineer viruses to build both the positively and negatively charged ends of a lithium-ion battery. We have posted about similar things previously, for example: Virus-Assembled BatteriesUsing Viruses to Construct Electrodes and Biological Molecular Motors. New virus-built battery could power cars, electronic devices

Gerbrand Ceder of materials science and Associate Professor Michael Strano of chemical engineering, genetically engineered viruses that first coat themselves with iron phosphate, then grab hold of carbon nanotubes to create a network of highly conductive material.

Because the viruses recognize and bind specifically to certain materials (carbon nanotubes in this case), each iron phosphate nanowire can be electrically “wired” to conducting carbon nanotube networks. Electrons can travel along the carbon nanotube networks, percolating throughout the electrodes to the iron phosphate and transferring energy in a very short time. The viruses are a common bacteriophage, which infect bacteria but are harmless to humans.

The team found that incorporating carbon nanotubes increases the cathode’s conductivity without adding too much weight to the battery. In lab tests, batteries with the new cathode material could be charged and discharged at least 100 times without losing any capacitance. That is fewer charge cycles than currently available lithium-ion batteries, but “we expect them to be able to go much longer,” Belcher said.

This is another great example of university research attempting to find potentially valuable solutions to societies needs. See other posts on using virus for productive purposes.

Carbon Nanotechnology in an 17th Century Damascus Sword

Carbon nanotechnology in an 17th century Damascus sword

Wootz, with its especially high carbon content of about 1.5%, should have been useless for sword-making. Nonetheless, the resulting sabres showed a seemingly impossible combination of hardness and malleability.

Amazingly, they found that the steel contained carbon nanotubes, each one just slightly larger than half a nanometre. Ten million could fit side by side on the head of a thumbtack.

It isn’t clear how ancient blacksmiths produced these nanotubes, but the researchers believe that the key to this process lay with small traces of metals in the wootz including vanadium, chromium, manganese, cobalt and nickel. Alternating hot and cold phases during manufacture caused these impurities to segregate out into planes. From there, they would have acted as catalysts for the formation of the carbon nanotubes, which in turn would have promoted the formation of the cementite nanowires.

By gradually refining their blade-making skills, these blacksmiths of centuries past were using nanotechnology at least 400 years before it became the scientific buzzword of the twenty-first century.

Related: Manipulating Carbon NanotubesMIT Energy Storage Using Carbon NanotubesUsing Bacteria to Carry Nanoparticles Into Cells

Seventh-grader’s Solar Cell Research

photo of William Yuan

Seventh-grader shines with solar cell research

Yuan worked on his project for the past two years with the encouragement of his science teacher Susan Duncan; support of his parents Gang Yuan and Zhiming Mei; and counsel of professional mentors Professor Chunfei Li of Portland State University’s Center for Nanofabrication and Electron Microscopy, Fred Li of Applied Materials Inc. and Professor Shaofan Li of the Department of Civil Engineering at the University of California – Berkeley.

“He is our youngest fellow in science that we’ve ever had,” Moessner said. “He is really spectacular. “His project will really make a difference in advancing the technology of solar cells. You would never know he’s 12 looking at the quality of his work.”

Beaverton boy lauded for solar cell invention

there have been many questions about the research by William Yuan. Some have even questioned whether he copied the research of others and claimed it as his own. That is far from the case. Yuan fully documented all of his sources and never tried to imply that he invented the 3D solar cell. He did create a new type of 3D solar cell that works for visible and UV light

William Yuan was awarded a 2008 Davidson Fellow award

In his project, “High Efficient 3-Dimensional Nanotube Solar Cell for Visible and UV Light,” William invented a novel solar panel that enables light absorption from visible to ultraviolet light. He designed carbon nanotubes to overcome the barriers of electron movement, doubling the light-electricity conversion efficiency. William also developed a model for solar towers and a computer program to simulate and optimize the tower parameters. His optimized design provides 500 times more light absorption than commercially-available solar cells and nine times more than the cutting-edge, three-dimensional solar cell.

Related: Solar Thermal in Desert, to Beat Coal by 2020Super Soaker Inventor Aims to Cut Solar Costs in HalfEngineering Student Contest Winners Design Artificial Limbposts on engineers

MIT Energy Storage Using Carbon Nanotubes

Images of different types of carbon nanotubes

MIT Researchers Fired up Over New Battery

Image / Michael Ströck, Images of different types of carbon nanotubes. Carbon nanotubes are key to MIT researchers’ efforts to improve on an energy storage device called an ultracapacitor. Larger image

Work at MIT’s Laboratory for Electromagnetic and Electronic Systems (LEES) holds out the promise of the first technologically significant and economically viable alternative to conventional batteries in more than 200 years.

The LEES ultracapacitor has the capacity to overcome this energy limitation by using vertically aligned, single-wall carbon nanotubes — one thirty-thousandth the diameter of a human hair and 100,000 times as long as they are wide. How does it work? Storage capacity in an ultracapacitor is proportional to the surface area of the electrodes. Today’s ultracapacitors use electrodes made of activated carbon, which is extremely porous and therefore has a very large surface area. However, the pores in the carbon are irregular in size and shape, which reduces efficiency. The vertically aligned nanotubes in the LEES ultracapacitor have a regular shape, and a size that is only several atomic diameters in width. The result is a significantly more effective surface area, which equates to significantly increased storage capacity.