Nanotechnology Today

How Close Are We To Molecular Manufacturing? (and Other Happenings in the World of Nanotechnology)

Thursday, November 14, 2013

How Cool Is This???

They alway say - it's not what you know, it's who you know.

Thankfully, I know enough people to put me in this position . . .

BOOK SIGNING


Friday, November 1, 2013

Should We Be More Than a Little Scared?

I know that I often write to promote the happenings in the Nanotech world - and it's usually positive.  But today I wonder whether we shouldn't be a little more cautious with what we do.

The Wilson Center has published an updated survey of products which (may) contain nano materials (list available here). They have varying levels of confirmation, from Category 1 (Extensively verified claim) to Category 5 (not advertised by manufacturer).  In reviewing some of the products, I came across Benny the Bear, a Category 2 (Verified Claim) which is a stuffed bear which claims:


“With the additive of Silver Nanoparticles, our product has been clinically proven to fight against harmful bacteria, molds and mites.” “This technology is widely seen in the medical industry. Silver Nanotechnology is being used to coat surgical tables and equipment to thwart micro organisms.”

Scientists reviewed various products and as relates to the stuffed bear found:

Fabrics, a plush toy, and cleaning products were most likely to release silver. Silver leached mainly via dissolution and was facilitated in media with high salt concentrations. Levels of silver to which children may potentially be exposed during the normal use of these consumer products is predicted to be low, and bioavailable silver is expected to be in ionic rather than particulate form.

The question, of course, is whether the fact that the low potential exposure levels is a good thing or a bad thing.  The company, of course, would like to claim that exposure is high - as they advertise the bear as exposing children to the benefits of nano silver, which is "clinically proven to fight against harmful bacteria, molds and mites."  Perhaps scientists would prefer otherwise.

The unspoken danger, of course, is that in addition to fighting against harmful bacteria, nano silver also kills beneficial bacteria - many of which live on and inside the human body and which are necessary for humans to maintain health.

I recently read an article discussing issues with over exposure to antibiotics and the negative consequences.  One example, was a gentleman who had an ear infection (one ear only) that simply could not be treated by medical doctors.  It turns out, the gentleman cured himself.  He (and don't ask why) pulled some ear wax out of his healthy ear and placed it in his infected ear.  Sure enough, the infection (that had been impervious to antibiotics) was cured.  What was the secret?  You guessed it - bacteria.  The bacteria that lived in his healthy ear (and presumably in his infected ear prior to the infection) warded off the dangerous bacteria/microorganisms and kept his ear environment in good health.

Another example in the article revolved around an individual with severe diarrhea.  Nothing the physicians did cured it - until the patient underwent a "stool transplant".  Yes, you read it correctly.  The surgeons removed stool from a healthy colon and transferred it into the patient - who's body, once populated with good bacteria, was able to return to a normal, healthy state.

Science's sometimes myopic view of the world can lead to unintended consequences.  By developing a teddy bear which releases nano silver meant to ward off bad bacteria, this company may promote a generation of children who lack proper good bacterial populations and cause untold ailments to be visited upon these innocent children.

Science certainly has been a benefit for society.  Yet is has also been a bane - let's hope these folks spend more time considering the consequences and less time thinking about money.



Wednesday, July 3, 2013

Efficiency Down, Energy Up



Science has spent the past several decades attempting to increase the efficiency of solar cells in order to make solar energy a viable alternative to fossil fuels.  The average solar cell has a 15-20% efficiency (i.e. converting 15-20% of solar energy into usable electricity).  Sharp Electronics has managed to develop a solar cell boasting 44.4% efficiency, however this is a concentrator system which requires lenses to concentrate sunlight onto the solar cells.  But the scientists at MIT are working on a solution that actually reduces the efficiency.  Huh?

Jeffrey Grossman, senior author of a new paper published in Nano Letters, is using nanotechnology in an effort to improve the functionality of solar cells.  Using graphene (a one-atom thick sheet of carbon atoms) and molybdenum disulfide (a one atom thick sheet of molybdenum and sulfur) together to form a 2 atom thick sheet produces a solar cell capable of converting sunlight to electricity at an efficiency of 1-2%.  While hardly efficient, because it is only 1 nanometer thick (1 billionth of a meter), they can be stacked to boost the overall efficiency of the system.  Pound for pound, this new material generates a 1,000 times more energy than conventional photovoltaics.  This can open the door for weight-sensitive applications such as aircraft or hard to access locations where transportation costs factor in.

While it is not yet manufactured in bulk, molybdenum disulfide is cheaper than silicon and opens the door to the potential for cheaper energy from the sun.

Friday, May 10, 2013

What Will You Do With Your Invisibility Cloak?



"Your father left this in my possession before he died. It is time it was returned to you. Use it well."
-       note from Albus Dumbledore to Harry Potter


While many people, both young and old alike, probably imagined a number of things they could do with a cloak of invisibility, they knew that, like Harry Potter himself, it was merely an object of fantasy.  At least back in 1997.  In 2013, fantasy has nearly met reality.

Back in 2006, researchers were able to develop a laboratory experiment whereby objects were made invisible in the microwave light range (just below the visible spectrum).  Scientists were able to bend light waves around the object, removing its shadow and making it appear invisible.

In 2011, scientist Xiang Zhang was able to develop a cloak that bends visible light around objects so that it appears flat and the image projected is that of the objects lying behind the cloaked object.  You can think of it as gravitational lensing (where a massive object (galaxy for example) (“Massive Object 1”) lies between our sight lines and that of another bright object (“Bright Object 2”).  In these instances, the gravity from the Massive Object 1 bends the light emitting from the Bright Object 2 around its edges so that the image of the Bright Object 2 actually appears as two objects on either side of the Massive Object 1.) except rather than merely projecting the light from the hidden object along side the object doing the hiding, it bends the light enough that light from the hidden object wraps around to the front of the object doing the hiding, resulting in the light waves from behind the object being projected to the viewer.  The 2011 experiment, however, dealt with the cloaking of microscopic object (about the size of a human red blood cell).

Recently, Yaroslav Urzhumov, of Duke University has developed a cloak made from a 3-D printer using plastic to make objects invisible in microwave range.  This cloak is specially designed with an algorithem used to calculate the location, size and shape of holes in the cloak to deflect light properly to make materials invisible in the microwave range.  He has run tests and believes that this process can be transferred to the visible light range in the not-too-distant future.  His simulations show that not only will a cloak as thin as one inch in diameter be able to make objects several meters in diameter invisible, but the cloaks will be able to be produced from transparent polymers and glass on (relatively) inexpensive home 3-D printers – which are currently available in several price ranges at or below $3000.

It’s possible that by the end of the decade, we can all be giving our children their very own invisibility cloaks.  The only question is what they will do with it and, perhaps more importantly, whether they will use it well.




3-D Printing of Microwave Invisibility Cloak

Get Your Own 3-D Printer (Cheap!)

Monday, April 29, 2013

MSRA (No Longer) A Big Deal?


A wide variety of pathogens that harm or kill are known as “pore-forming” toxins.  These pore-forming toxins destroy cells by perforating the cell membranes, disrupting their internal chemical balance and causing them to burst.   Pore-forming toxins compose about one-quarter of all known protein toxins and increase the infectivity and severity of bacterial diseases, and include E. coli, MSRA, anthrax and snake venom. 

Scientists at the University of California – San Diego have developed what they are terming a “nanosponge” which neutralizes these toxins and renders them ineffective.  Using a technique developed by one of the research team several years earlier, the scientists are able to wrap nano-sized spheres of a lactic acid byproduct with the membrane of a red blood cell.  The membrane from a single red blood cell can be used to wrap, literally, thousands of the nanosponges (which are 3000x smaller than a red blood cell).  The process appears to be repeatable and scalable, so that not much blood is required to develop these nanosponges.  By encasing the lactic acid byproduct in the membrane of a red blood cell, the nanosponge can travel freely in the bloodstream without being viewed as a foreign body (and thus remaining free from the body’s immuno-response processes).  These tiny nanosponges then circulate freely through the body and attract 10s to 100s of the pore-forming toxins each and render them ineffective by trapping them onto the nanosponge, where they continue to circulate in the bloodstream until they are metabolized in the liver with no ill effects.  Because of their small size, thousands can be circulated in the blood stream, outnumbering the number of red blood cells and intercepting the toxins.

In lab tests, 18 mice were injected with a lethal dose of MSRA.  Nine were subsequently injected with the nanosponges.  All the non-inoculated mice died, whereas only 1 mouse that received the nanosponge injection died.

If this method proves successful in human trial, science will be able to treat a wide variety of toxins from MSRA to bee venom.


CITES:




Wednesday, April 17, 2013

THERE IS HOPE . . . .


While there are 18,000 kidney transplants performed annually in the U.S., the sad truth is that another 100,000 persons are waiting for suitable organs (not to mention the 400,000 who are required to undergo dialysis).  Hopefully, however, the next decade will bring that figure down to near zero.

In a recent Nature Medicine article, it was disclosed that science is inching ever-closer to manufacturing replacement organs.  Investigators at Massachusetts General Hospital (using rats) have developed a procedure whereby the non-functioning or donor organ is removed from the host and then, using a detergent solution, all the living cells of the donor organ are removed, leaving only the organ’s scaffolding.  Then, the organ is repopulated with the proper cells (in the case of a kidney, with endothelial cells to replace the vascular system lining, and kidney cells for remaining structure).  By adjusting the pressure through which cells are passed through the organ (through the renal artery for repopulating the vascular portions of the organ and through the ureter for populating the kidney tissue), the scientists were able to seed the organ with the appropriate number of cells, which were then implanted in the donee.

While the function of the kidneys were greatly reduced compared to normal kidneys, they did, in fact, start producing urine as soon as the blood supply was restored and there was no evidence of any clotting or bleeding.  The researchers believe that the reduced functionality may have to do with the immaturity of the cells used to repopulate the kidney (the scientists in this study used kidney cells from newborn rats).  It is possible that by allowing the seed cells to mature longer, full functionality could be obtained.

The positives of this research are many.  By using the damaged organ of the individual, the scaffolding upon which the new organ is built is a perfect match, as it is the patient’s own kidney to begin with.  Furthermore, through the use of stem cell research (which, by the way, has produced pluripotent cells from adult cells – negating any complaints about fetal stem cell use), science may be able to repopulate the scaffolding with the patient’s own cells – removing any complications from organ rejection and negating the need for anti-rejection drugs.

Scientists have successfully stripped cells from human kidneys to produce viable human scaffolding.    This technique has also been done on hearts, lungs and livers.  While not perfected and certainly not yet ready for human trial, it does provide hope that the next decade will find science up to the challenge of those in need of new organs.

Regeneration and experimental orthotopic transplantation of bioengineered kidney.  Song, J.J., Guyette, J.P., Gilpin, S.E., Gonzalez, G., Vacanti, J.P., and Ott, H.C. Nature Medicine (2013) doi:10.1038/nm.3154 Published online 14 April 2013


Full article available with subscription

Monday, April 8, 2013

Free Energy?


While the nation seeks to ween itself from our petrol society - science may allow us to continue our reliance upon fossil fuels while preserving the environment as well.

How can this be?  One possible method is through the use of bioengineering.

Joule is a company which is attempting to do just this.  The scientists of this company have - through genetic engineering - developed a microbe (two actually) which basically eats sunlight and CO2, yes, that's what is the cause of global warming, and excretes Diesel (or Ethanol).  They recently underwent testing with a large scale plant demonstration plant which has proved successful.   What does all this mean?

By setting up these plants near coal plants (or other high CO2, emission plants) Joule can direct the  CO2, into their plants, which will be fed to the microbes (along with sunlight) and convert the  COinto usable fuels.  This is a net zero fuel since all  CO2 that would discharged by the biofuel was pulled out of the atmosphere.  In addition to weaning us of foreign sources of fuel - as well as its neutral carbon footprint - it operates exactly like diesel and ethanol which makes any need to modify our vehicles or change the existing infrastructure for delivery a non-issue.

I have been following this company for several years.  Originally, they guesstimated that they could produce either of these fuels at about $40 per barrel (YES, $40 - last time crude was $40 a barrel, prices were around $1.75 gallon).  Lately, however, I've noticed that the claims for price have been modified to "competitive".  It is not clear whether this is a result of higher than expected costs of production at the larger scale facility, or whether good old Greed is to blame.  Given the current climate, it's conceivable that a company would receive plenty of feel-good press if they provided an alternative to traditional fossil fuels at the same (or near the same) as current costs - even if their profit margins were 300% greater than need be.

Additionally, they have entered into a contract with Audi to help develop carbon-neutral vehicles.  This means that either the diesel or ethanol are not quite like what we use now (requiring some vehicular modifications) or that are simply going to market this as a GREEN technology, irrespective of production costs, and make no efforts to reduce the cost of energy.

What this company chooses to do awaits to be seen.  But it does provide hope that we can ignore Middle-Eastern despots and maybe even pay less for energy.