Questions for Ghidewon Arefe

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Durring the summer of 2006 Ghidewon Arefe answered questions about nanotechnology.

Your Comments, Thoughts, Questions, Ideas

Joe's picture
Joe says:

An often cited worst-case scenario regarding nanotechnology is "grey goo" - what is "grey goo" and how serious do you think this risk is?

posted on Mon, 07/10/2006 - 3:26pm
Ghidewon Arefe's picture
Ghidewon Arefe says:

"Grey goo" is a science fiction term that refers to nanometer sized objects that replicate and grow uncontrollably to the point where they can take over the world! In reality, this will not happen as the laws of nature prevent these small objects from gaining enough energy to form a "grey goo" in the first place.

posted on Mon, 07/17/2006 - 11:39am
bryan kennedy's picture

Is nanotechnology more exciting to you than other types of engineering? Why?

posted on Mon, 07/10/2006 - 4:24pm
Ghidewon Arefe's picture
Ghidewon Arefe says:

The exciting part of nanotechnology is that it has an effect on all types of engineering. Nanotechnology research requires a great deal of teamwork between scientists and engineers from different fields. As a relatively new field, working in nanotechnology is like exploring uncharted land, you never know what you may come across.

posted on Mon, 07/17/2006 - 11:45am
Liza's picture
Liza says:

What kinds of tools do you use in your research? How do you work with materials you can't see, even under a microscope?

posted on Mon, 07/10/2006 - 4:39pm
Ghidewon Arefe's picture
Ghidewon Arefe says:

Since quantum dots are so small, we use special tools that allow us to image objects on the order of a nanometer. Transmission electron microscopy (or TEM for short) is an imaging technique that is capable of capturing images of objects as small as a quantum dot. Instead of using a beam of light (like is used in a microscope), a beam of electrons is used for imaging. This works because electrons can have their behavior tuned just right to allow for a high resolution image. However, with enough material, I can study the behavior of my quantum dots just by looking at them with a UV lamp. I can make estimations of their size based on the color of their fluorescence. For example, quantum dots with a red glow will be larger than quantum dots with a bue glow.

posted on Tue, 07/18/2006 - 8:19pm
Anonymous's picture
Anonymous says:

What place does nanotechnology have in quantum physics?

posted on Sat, 07/15/2006 - 12:46pm
Ghidewon Arefe's picture
Ghidewon Arefe says:

Quantum physics actually provides some explanation for the weird behavior of objects that are onlly nanometers in size. For example, the silicon that I use in my research fluoresces (that is, it is able to emit light). Silicon only behaves this way when it is a few nanometers in size, also known as a nanoparticle, due to the effects of quantum physics. The energy required to release light from silicon usually gets lost within the material when it is in its bulk (normal) form. However, when you trap that same energy into silicon when it is a mere nanoparticle, it is more likely to release that energy in the form of light due to its extremely small size. And that is quantum physics in a nutshell (or a nanoparticle in this case).

posted on Tue, 07/25/2006 - 12:43pm
Alyssa's picture
Alyssa says:

How do you make the Quantum Dots?

posted on Sat, 07/15/2006 - 1:09pm
Ghidewon Arefe's picture
Ghidewon Arefe says:

I start with a combination of gases, the most important one being silane which is comprised of silicon. The silane flows through a plasma region where the gas becomes highly excited. The Northern Lights are an example of a plasma on a large scale, as are fluorescent light bulbs. In both cases gases become excited with electrical energy and glow brilliant colors. I use a much smaller plasma that excites the silicon atoms in the silane gas flow, and with a stroke of physics and a touch of engineering, groups of silicon atoms will come together to form crystals on the order of a nanometer. These are also known as nanocrystals. Since we're dealing with nanocrystals made out of silicon (a semiconductor) they can be called quantum dots.
After the quantum dots are formed in the plasma, they crash into a thin steel mesh which I can later pull out of the system.

posted on Tue, 07/18/2006 - 8:27pm
Crystal's picture
Crystal says:

How many current labs are there designated towards nanotechnology research and have you heard of plans for a new nanotechnology lab in South Dakota?

posted on Mon, 07/17/2006 - 5:50pm
Ghidewon Arefe's picture
Ghidewon Arefe says:

At the University of Minnesota Twin Cities campus, we have labs working with nanotechnology in mechanical engineering, electrical engineering, chemical engineering, material science, physics, chemistry, as well as numerous other labs affiliated with the health sciences. There are research groups across the globe that are dealing with nanotechnology so it's hard to give an exact number. I believe South Dakota's governor is pushing for the development of a state of the art nanotechnology research center, but I'm not sure when it is supposed to open.

posted on Tue, 07/18/2006 - 8:34pm
Maru's picture
Maru says:

Who are some prominent women contributing to nanotechnology research?

posted on Mon, 07/17/2006 - 6:43pm
Ghidewon Arefe's picture
Ghidewon Arefe says:

Nanotechnology is still relatively young field, but there are several professors and graduate students at the University of Minnesota that are making great strides in their research. Check out this link to some local researchers http://www.nanoigert.umn.edu/.

posted on Tue, 07/18/2006 - 8:41pm
Byron McGuire's picture
Byron McGuire says:

I still dont know what nanotechnology is, exactly. What is nanotechnology?

posted on Tue, 07/18/2006 - 3:26pm
Ghidewon Arefe's picture
Ghidewon Arefe says:

Nanotechnology is a field of technology the deals with objects on the order of a nano-meter (one billionth of a meter). Some materials behave differently when they are on the order of a nanometer. By engineering materials that are only a few nanometers in size, we can take advantage of those unique properties.

posted on Tue, 07/18/2006 - 8:45pm
isaac's picture
isaac says:

DO you think there ever going to be nanities like in movies that help people?

posted on Thu, 07/20/2006 - 2:32pm
Ghidewon Arefe's picture
Ghidewon Arefe says:

Good question Isaac. I'm not sure if we'll see nanities like in the movies anytime soon, and I don't know of any research in this field. But then again, who knows what will happen in the future. Some people worry about nanotechnology resulting in some form of gray goo that grows out of control and takes over the world. I do not see this happening at all (but I would take helpful nanities over gray goo any day!). There are several forms of nanotechnology that exist today that are helping people, even most sunscreens contain nanoparticles to protect you from harmful UV rays.

posted on Tue, 07/25/2006 - 12:51pm
Sir Diddy VII of Wiltshire's picture
Sir Diddy VII of Wiltshire says:

Dear Mr. Arefe:

According to howstuffworks.com, IBM successfully put to work an atomic force microscopy instrument in the year 1990 and successfully positioned individual atoms using this device (spelling “IBM” in atoms). Does IBM’s successful manipulation of individual atoms suggest that in the future human beings will be able to arrange individual atoms into any form found in nature? If so, and assuming that atoms truly are the building blocks of life, what do you see as the religious and cultural implications of such developments? Will scientists be able to build “people” from the ground up? Could the U.S. build an army of superhuman fighting soldiers with the strength of Jean-Claude Van Damme and the supple cat-like reflexes of Jet Li?

posted on Fri, 07/21/2006 - 3:49pm
Ghidewon Arefe's picture
Ghidewon Arefe says:

Your line of questioning is impressive Sir Diddy VII of Wiltshire, perhaps you should consider a career in law (if you haven't already). Your ability to look into the future amazes me, we could use more people like you in nanotechnology. Work on "nano-clones" is alreay taking place at a super secret research facility in the Pacific northwest. Just kidding (as far as I know). Truthfully, if something like that were to happen, it wouldn't be in our lifetime. In order to mimic nature, scientists would have to be able to completely control all the forces of nature which is not currently possible. Being able to physically arrange atoms into a pattern is one thing, but getting them to support a lifeform is a whole new ballgame. As far as the social implications of such a development, I'm sure it'd cause an uproar as do current aspects of nanotechnology. Who knows what the future holds, but if your idea does come true one day, I'm sure the superhuman soldiers would start out more like Tom Cruise and work their way up to Jean-Claude Van Damme status. And of course, a nano-clone of Chuck Norris would lead the commando unit.

posted on Wed, 07/26/2006 - 5:08pm
Anonymous's picture
Anonymous says:

Do you see nantechnology being able to replace traditional cancer treatments like chemo and radiation?

posted on Sat, 07/22/2006 - 4:25pm
Ghidewon Arefe's picture
Ghidewon Arefe says:

That is an excellent question. While cancer treatments like chemotherapy have proven to be useful in fighting cancer, the side effects can be pretty severe. An advantage of using nanotechnology for cancer treatment will be to target and destroy specific cancer tumors with minimal or no damage to the surrounding healthy cells. Although these treatments haven't been approved for clinical use yet, I do believe that nanotechnology based treatments can replace traditional cancer treatments.

posted on Wed, 07/26/2006 - 3:53pm
Adam Henke's picture
Adam Henke says:

What will be the one biggest thing you think nanotechnology will help us with in the furture?

posted on Sat, 07/22/2006 - 5:25pm
Ghidewon Arefe's picture
Ghidewon Arefe says:

I like the way you think Adam. My guess is that nanotechnology will have the biggest effect on medical advancements. While the information technology (computers, cell phones, electronic gadgets) have become an important part of our lives due to advances with nanotechnology, I think we'll see radical changes to the way diseases are diagnosed and treated. With nanotechnology, we are able to engineer objects that are in most cases the same size (or even smaller) than cells. For example, the quantum dots that I make in my lab are simply particles of silicon that are really small. Some researchers are working on attaching certain types of medication to these types of particles that can then deliver the medicine exactly where it needs to go. So, I guess you can say that really small stuff will have a really big effect on our future.

posted on Wed, 07/26/2006 - 4:16pm
Joe's picture
Joe says:

How do you measure stuff in the nano world? What scales of measurement do you use and what equipment do you use?

posted on Mon, 07/24/2006 - 10:55am
Ghidewon Arefe's picture
Ghidewon Arefe says:

A popular tool for measuring stuff in the nanoworld is an atomic force microscope, or AFM for short. An AFM uses a probe with a really small tip to feel its way over a surface covered with nano-sized material. A computer attached to the probe will take in information such as the change in probe height to draw an image of what the surface looks like. An easy way to think about how this works would be to dump a bunch of sugar cubes into a box, and without looking, stick your hand in the box and feel your way around. Then, with your free hand, draw what the sugar cubes (or whatever else you decide to throw in the box) look like.

In the nanoworld, we typically use nanometers as the unit of length measurement. A nanometer is one billionith of a meter. If you had a stack of one billion $1 dollar bills and pulled out $1 dollar that would be the same as pulling out one nanometer from a meter. Typically, tools such as the AFM take care of the measuring, otherwise, we'd need really really really really small rulers.

posted on Wed, 07/26/2006 - 4:34pm
Marla's picture
Marla says:

Would there be any side effects of nanotechnology cancer treatments? If so, what would those be?

posted on Tue, 07/25/2006 - 2:43pm
Ghidewon Arefe's picture
Ghidewon Arefe says:

I see that you are thinking ahead Maria. One type of quantum dot (also known as a nanoparticle) that researchers are using for cancer treatment contains cadmium which is known to be toxic. Cadmuim is used because it serves as a great nano-delivery vehicle for cancer medication, but to prevent the toxicity of cadmium from hurting the patient, the particles are coated with a protective layer. The nice thing about my research is that we are using silicon nanoparticles which are non-toxic. My guess is that those nanoparticles that don't make it to the cancer cells will eventually work their way out of the body as waste. It will still be important for me to see how my quantum dots behave in cell systems in the laboratory before we move up to targeting cancer cells in animal models.

posted on Thu, 07/27/2006 - 8:23pm
Anonymous's picture
Anonymous says:

How long has nanotechnology been a field of study?

posted on Tue, 07/25/2006 - 8:14pm
Ghidewon Arefe's picture
Ghidewon Arefe says:

I'm sure different people will have different answers for this one, but my belief is that the field of nanotechnology started with a lecture entitled "There's Plenty of Room at the Bottom" by Richard Feynman in the late 1950's. Feynman was a prominent American physicist who, in my opinion, was a pure genius. Not only was this brilliant man a Nobel prize winner, but he was a well rounded character who seemed passionate about learning about everything around him. I think that it was his brilliant insight into the fact that there was still much science and engineering to conquer at really small scales that kicked off the field of nanotechnology.

posted on Thu, 07/27/2006 - 8:39pm
From the Museum Floor's picture

As a graduate student do you get to decide your own research questions or do you have to just research whatever your professors want you to research?

posted on Thu, 07/27/2006 - 6:36pm
Ghidewon Arefe's picture
Ghidewon Arefe says:

I'm sure that it varies for different people, but in my experience I look to my professors, Dr. Hubel and Dr. Kortshagen, for guidance as to which direction I should take with my research. They have much more experience with this research than I do, but they have been great about giving me direction. The goal of a graduate program is to guide students into become independent researchers. Towards the end of my program I will be in a position where I'll be an expert in my research and hopefully people will then look to me for answers (and hopefully I'll have them!). In addition to my professors, I look to my fellow graduate students who are farther along in their programs for technical know-how and general advice. Lorenzo Mangolini, also from the Kortshagen Lab, is actually a pioneer in the field of silicon quantum dots, and he has been a great guy to go to whenever I need help with my research.

posted on Thu, 07/27/2006 - 8:45pm
From the Museum Floor's picture

How do you control the size of the "dots" and how to you get the antibodies to "stick" to them?

posted on Thu, 07/27/2006 - 6:37pm
Ghidewon Arefe's picture
Ghidewon Arefe says:

I'd like to say with "magic" but there's more to it than that. The size of my quantum dots are controlled by the amount of material I use in my process. I use a gas (like air, not like the stuff you put in your car) called silane which contains silicon atoms to make my dots. More silane means bigger dots, less silane means smaller dots.

I'm working with researchers at the University of Minnesota's Cancer Center to figure out how to stick antibodies to the quantum dots. The quantum dots are encapsulated with a shell that we can "spike" with antibodes that will be used to target the cancer cells. This is still a work in progress but previous work with similar methods was successfull so we should be able to do it with our new silicon quantum dots as well.

posted on Thu, 07/27/2006 - 8:53pm
Anonymous's picture
Anonymous says:

i see there are needles in the nano showcase, what are they for?

posted on Sat, 07/29/2006 - 1:58pm
Ghidewon Arefe's picture
Ghidewon Arefe says:

Needles are used to inject nanoparticles into the bloodstream. Although we haven't done with this humans yet, we have tried this on a mouse. Instead of targeting cancer cells, we tried to target liver cells since they are much easier to detect. The liver cell targeting silicon nanoparticles were injected through a vein in the tail and made their way through the circulatory system. When the the got near the liver, most of the nanoparticles got off the the main vein and made their way to the liver. It's kind of line a riding on the New York City subway system. You can get on at many different points throughout the city, but you know when and where to get off the train.

posted on Wed, 08/02/2006 - 11:38am
Gnarls Barkley's picture
Gnarls Barkley says:

Mr. Arefe,

I've been giving serious consideration to abandoning my recording career in favor of pursuing my first love, nanotech research. What do you find most enjoyable about your work? And what do you find most frustrating? Does it make you crazy?

posted on Mon, 07/31/2006 - 10:48am
Ghidewon Arefe's picture
Ghidewon Arefe says:

I must say Mr. Barkley, I'm not suprised by your interest in nanotechnology research. I can easily see how your musical genius translates into scientific brilliance. While I do encourage you to pursue your first love, I do believe you are doing pretty well in the music business.

The part of my work that I enjoy the most is running experiments. The most frustrating....running experiments. Building new experimental set-ups and coming up with unique ideas that have never been tried before is a lot of fun. You never know what your end product will look like, but you hope that your original guesses were right. However, sometimes things just don't work out with your experiment and there isn't an obvious answer as to what's wrong. It can be frustrating, but with persistance, I usually work my way through it and throw down in the end. It's kind of like running in a marathon. You might start to cramp up half-way through the race, but you fight through it and make it to the finish line. Does this make me crazy....possibly.

posted on Tue, 08/01/2006 - 11:39am
Art L.'s picture
Art L. says:

In the book "Prey" by Micheal Criton, nanotechnology is a constant source of fear. I realize that the novel is indeed science fiction, but do the associated risks of nanotechnology pulling a terminator apply?

posted on Mon, 07/31/2006 - 11:51am
Ghidewon Arefe's picture
Ghidewon Arefe says:

Art, your question is one that I've discussed previously with some of my friends. Although I've never read "Prey", my understanding is that it deals with a swarm of self-replicating (that is, growing out of control) nanomaterial (or nano-bots in this case). While there are risks associated with nanotechnology (as with any branch of science), I feel confident in saying that you need not worry about nanotechnology "pulling a Terminator." In order for self-replication to take place, a source of energy is needed to continue this process. Besides, even if it were possible, a high level of intelligence would be necessary to overtake humans.

I'm struggling to come up with a good analogy here, but this is the best I can come up with right now, so hold on: Let's use Takeru Kobayashi, Nathan's Hot Dog Eating Contest champion the last 6 years, as an example. Say Kobayashi is your first "nano-bot," and after eating a hot dog, a clone of him is spontaneously produced. Now Kobayashi and his clone each eat another hot dog, self-replicate, and so on and on.... If this process were to continue, we would have an army of hot-dog eating champions that never seems to stop growing. However, this self-replication process would come to a halt by simply taking away the hot dogs, Kobayashi's source of energy.

posted on Wed, 08/02/2006 - 9:59am
Anonymous's picture
Anonymous says:

Are you using silicon nanoparticles for cancer detection on people yet? How soon would that be possible?

posted on Mon, 07/31/2006 - 8:57pm
Ghidewon Arefe's picture
Ghidewon Arefe says:

That's what undergraduate students are for. I'm only kidding. We haven't used silicon nanoparticles on humans yet. As with all medical technologies, years of research is required before testing on humans can occur. In order to perform clinical studies, the US government must approve it first before we can proceed. While the approval process can be lengthy, it is a good way to protect the interests and health of people. Since this research project is relatively new (a couple of years old), I don't see these silicon nanoparticles being used on humans for at least a decade. Once we can engineer a silicon nanoparticle that is perfect for a biological environment and is easily attracted to cancer cells, we'll move up to using animal models to see how they work in a living system.

posted on Wed, 08/02/2006 - 10:09am
Anonymous's picture
Anonymous says:

Have you read "Snowcrash"?

posted on Mon, 07/31/2006 - 9:03pm
Ghidewon Arefe's picture
Ghidewon Arefe says:

Sorry, Anonymous, I have not read "Snowcrash." To be honest, it's been a while since I've made the time to read a novel. I spend most of my reading time on reviewing scientific articles or textbooks for my classwork. Each week I try to read through The Economist (a weekly magazine) to stay up to date with what's going on in the world. The last novel that I read was Earnest Hemingway's "A Farewell to Arms," which, to be honest, gets more hype than it deserves (but that's an entirely different discussion). Using an extenisve research database (Google), I was able to find out that "Snowcrash" is a of sci-fi variety. While I don't typically read sci-fi (I live it), it looks pretty interesting and I'll be sure to add it to my list.

posted on Wed, 08/02/2006 - 10:21am
Anonymous's picture
Anonymous says:

Could nanotechnology be used to alter people's appearences?

posted on Fri, 08/04/2006 - 10:30am
Ghidewon Arefe's picture
Ghidewon Arefe says:

Well, I haven't thought of that idea before. While I don't know of any research in this field, I suppose it is possible. The only idea I can think of is with some sort of cream or makeup that contains nanoparticles. Certain sunscreens contain nanoparticles which enhance the ability to block harmful rays from the sun. Maybe a similar idea could be used to alter a person's skin tone. Other than that, improvements in equipement used to manufacture appearance altering devices (lasers, etc.) could indirectly benefit from electronic improvements based on nanotechnology.

posted on Sat, 08/05/2006 - 11:04am
Bryan 23's picture
Bryan 23 says:

The research you are undertakingis very exciting.

I am wondering about the possibility of "programming" nano-bots to perform more complex tasks....tasks that may contain multiple actions or which may see the nano-bot using some kind of artificial intelligence.

Is there a way to use these as a part of a larger artificial intelligence system with the bot taking commands remotely?

I guess what I am getting at is the idea of having some of microcomputer on board that allows one to give commands and reprogram a bot on the fly as it comletes a task or to give it the power to change its own behavior as it acts?

posted on Sat, 08/05/2006 - 11:18am
Ghidewon Arefe's picture
Ghidewon Arefe says:

Good question, Bryan 23, sounds like you've been giving this subject plenty of thought. While I'm no expert at "nano-bots," my guess is that your idea would not hold up entirely in practice. Typically, in order to assume some sort of "control" of nano scale materials (such as my quantum dots), we allow nature to do the controling. Quantum dots that are spiked with antibodies are attracted to specific cells in the body due to chemical (electrostatic) attraction.

For a nanobot to be remotely controlled, you would need some sort of wireless communication to take place between the controller and the device (the nanobot in this case). Unfortunately, microcomputers would be too large to fit on a nanobot. While the movement of nanoparticles made from magnetic material can be controlled by magnets, it is a natural force and not artifical intelligence that dictates the behavior of the particles. And besides, nanobots currently do not exist and will be extremely hard to achiveve.

This is truly an entriguing idea, however, I don't see this happening (at least, anytime soon**).

**This statement provides defense against "ha, told you so" scenarios.

posted on Tue, 08/08/2006 - 10:53am
Matt's picture
Matt says:

Your research involving breast cancer seems quite involved and complicated. Do you have to do everything by yourself or do you get to collaborate with others?

posted on Thu, 08/10/2006 - 3:55am
Ghidewon Arefe's picture
Ghidewon Arefe says:

You are absolutely right, Matt. This project is a collaboration that involves several researchers from different fields. Dr. Allison Hubel (Mechanical Engineering) is my primary advisor and is an expert in biomechanics. She is the driving force behind this research. Dr. Uwe Kortshagen (Mechanical Engineering/Physics) is my other advisor and his lab pioneered the process we use to create our quantum dots. Lorenzo Mangolini (Mechanical Engineering) is a PhD candidate in the Kortshagen Lab who came up with the process that makes luminescent silicon particles. Dr. Hua Zhang (Biology) from the Cancer Center has been working on the encapsulation process under direction from Dr. Chun Wang (Biomedical Engineering). Dr. Doug Yee, MD (Cancer Center) is working on the targeting of cancer cells. The images of the mouse we have on display at the Science Museum's Science Buzz display were taken by Jerry Sedgewick (Biomedical Imaging and Processing Lab). Jerry has developed a novel method for imaging our quantum dots once they are inside a mouse. Dr. Gretchen Unger is a local researcher who has started a company, Genesegues (Chaska, MN), that has pioneered the encapsulation technique used on the quantum dots used for our initial in-vivo imaging study.

And lastly (orchestra starts playing) I'd like to thank the Academy, the Hollywood Foreign Press, the good people of the NISE network, the Science Museum of Minnesota, all my fans for their support, and of course my family.

posted on Thu, 08/10/2006 - 10:04am
Albert J. Willhiem Jr. IV, Earl of Lincolnshire's picture
Albert J. Willhiem Jr. IV, Earl of Lincolnshire says:

You are attempting to use silicon quantum dots to detect breast cancer. It appears that silicon has been chosen because it is “not poisonous,” whereas the majority of quantum dots are made with elements poisonous to humans (cadmium and selenium). Are you sure silicon is not poisonous? Have you ever purchased a pair of shoes, or perhaps delicious beef jerky? As I recall those products tend to come with small packets of “silica.” Said packets are clearly marked “do not eat.” I sir, am no chemist, but I do know that “silica” and “silicon” sound remarkably alike. I also know that “do not eat” means “do not eat.” As such, I would like assurances that silicon quantum dots will not end up in fact giving me cancer before detecting it (or having any other undesirable effects on my thus far splendidly functioning body). Thank you.

posted on Thu, 08/10/2006 - 4:24am
Ghidewon Arefe's picture
Ghidewon Arefe says:

I see you've done your research, Earl. Quantum dots that are made from cadmium or selenium are indeed toxic. Researchers that use those materials typically put a coating over their quantum dots in order to prevent any ill effects. The nice thing about using silicon for quantum dots is that it is non-toxic. So even if a protective coating or encapsulation were to disappear over time, the exposed quantum dot would not be harmful.

The small silica packets that are included in a shoe box acts as a desiccator, that is, it absorbs moisture to keep the contents of the box dry. Silica is another name for silicon oxide, a material that has two oxygen atoms for every silicon atom. Everyday materials such as glass are comprised of silicon oxide. The silica in the packets (also referred to as silica gel, even though it is solid) is just a different form of silicon oxide. While the silicon oxide is non-toxic, the silica beads in the packet are treated with cobalt chloride, which is a highly toxic carcinogenic, as a moisture indicator. When the silica packet is dry, cobalt chloride is blue, when it is moist, the color turns pink. The "do not eat" warning is due to the color indicating chemical and not necessarily the silica. My advice to you, stay off the silica packets, as well as the beef jerky. Just say NO, kids.

posted on Fri, 08/11/2006 - 4:23pm
Anonymous's picture
Anonymous says:

How else do you think nanotechnology will be used in the field of medicine in the next ten years?

posted on Thu, 08/10/2006 - 7:46pm
Ghidewon Arefe's picture
Ghidewon Arefe says:

Excellent question. In addition to imaging cancer cells (assuming I actually graduate in the next ten years), cancer treatment will also make strides using nanotechnology. Some researchers are using gold nanoparticles or even carbon nanotubes to destroy cancer cells. Once the carbon nanotube has found the cancer cell, heating up the nanotube with a laser will primarily destroy the turor around it while leaving the surrounding healthy cells untouched. This research is an ongoing effort, but with time, I believe it will make its way to clinical trials.

A research group at the University of California - San Diego has been working on what they call a "smart" petri dish which is able to detect certain toxins. This device is comprised of porous silicon (that is, silicon with a lot of tiny holes) that allows them to control light which strikes the sample. While I don't have much of a biology background (I'm really a physicist posing as an engineer), I believe they look for changes in cell shape and optical properties to determine the adverse effects of certain chemicals.

Other groups are looking at repairing nerves to implating extremely small sensors in the body using nanotechnology. While these technologies won't be available to people in the next 10 years, I think significant progress is being made in the right direction.

posted on Wed, 08/16/2006 - 12:07pm
Anonymous's picture
Anonymous says:

what are some of the pharmaceuticals that are being looked at using nano technology?

posted on Sun, 08/13/2006 - 5:28pm
Ghidewon Arefe's picture
Ghidewon Arefe says:

Most of the research I'm aware of deals with the detection and treatment of cancer. However, some researachers are looking at using nanoparticles as a "delivery vehicle" to carry specific types of medicine to specific parts of the body.

I do recall reading something about a research group out of UCLA that has developed a "nanospring" to mechanically alter the behavior of specific cells. Typically, this is done using amino acids, that is, by changing the chemistry of the enzymes. The nanospring is essentially a bunch of well engineered DNA molecules that are placed in a specific location to mechanically "push" on an enzyme. To be perfectly honest, as a scientist with a background in the physical sciences, I'm not quite sure how this mechanical interaction alters the cells behavior. The fact that they can make a nanospring is pretty cool though.

posted on Sat, 08/19/2006 - 5:41pm
Anonymous's picture
Anonymous says:

can nano technology save oceans rivers lakes and etc from pullotion of oil and gas leakages?

posted on Sun, 08/13/2006 - 9:35pm
Ghidewon Arefe's picture
Ghidewon Arefe says:

Absolutely. Some researchers have created nanoparticles that react with specific pollutants in water or in the ground. When the nanoparicles come into contact with the pollutants, a chemical reaction takes place which converts the pollutant into a less-toxic substance. The end result is either a space with less pollution or a type of pollutant that is easier to filter out and remove.

Another way to think of this problem is with the improvement of electronic sensors and safety equipment used in the transportation of dangerous materials. Advances in the electronics industry based on nanoscale breakthroughs has enabled enormous improvements in the electronic devices used to monitor pipelines and fuel tanks on ships. With better technology, we can monitor hazardous materials closely and anticipate problems before they happen.

posted on Sun, 08/20/2006 - 1:07pm
Ward's picture
Ward says:

What are some examples of things that behave differently on a nanoscale, or when paired with some sort of nanotechnology, and why do they behave differently?

posted on Mon, 08/14/2006 - 3:59pm
Ghidewon Arefe's picture
Ghidewon Arefe says:

A great example of a common material that behaves differently on the nanoscale is aluminum. Most people are familiar with the rust that develops on aluminum surfaces over long periods of time. With aluminum nanoparticles, this rusting process, known as oxidation, happens much faster because of their small surface area to volume ratio. Aluminum nanoparticles are being looked at as a propellant for use on the space shuttle. The fast reaction time of these particles would make them ideal for applications in which you want a huge amount of energy released quickly.

If you are familiar with the equations that are used to calculate the surface area and volume of sphere, you would see that surface area is dependent on (radius x radius) and volume is dependent on (radius x radius x radius). This means that for a sphere with a really small radius (like a nanoparticle), volume does not play a dominant role in the sphere's behavior.

If that "mathematical" description doesn't jive, try this instead: Image you have two balls, a beach ball and a ping-pong ball. Let's say you fill the inside of each ball with red paint and you paint the outside of each ball with blue paint. As you can imagine, you would need a lot more red paint than blue paint for the beach ball due to its size. The same is true of the ping-pong ball, but not to the same extent. If you tried this out with balls much smaller than a ping-pong ball, you'd see that the smaller you went, the smaller the difference in the amount of red and blue paint.

posted on Tue, 08/22/2006 - 1:51pm
Lisa's picture
Lisa says:

Why is it easier for nanotechnology to be made from simpler elements? (the first few rows of the periodic table, as opposed to the last few rows)

posted on Thu, 08/17/2006 - 3:40pm
Ghidewon Arefe's picture
Ghidewon Arefe says:

This is probably one of the most insightful questions I've recieved yet. While scientists do tend to play with "upper table" elements such as silicon, aluminum, and carbon, there are some "lower table" elements that are important as well. Elements such as tungsten, platinum, and even lead are being used in their nano form for applications such as special coatings, cancer detection or in electronics. The most popular nanoparticle, in my opinion, is gold (number 79 out of 114 on the periodic table of elements). Gold is a great electrical and thermal conductor which makes it ideal for many applications. Gold nanoparticles that target cancer cells can be heated up to kill the cancer cells in their vicinity with minimal damage to the healthy cells. Sugar-coated gold nanoparticles are being used by a research group in the United Kingdom as a bio-toxin detector. When the nanoparticles and sugars are exposed to specific toxins, a chemical reaction takes place that results in a change in color. Although this is still in the research phase, it is a technology that could see mainstream use in a matter of years.

posted on Tue, 08/22/2006 - 6:01pm
Anonymous's picture
Anonymous says:

How are you able to bond the silicon dots to the cancerous cells and differentiate between healthy and cancerous cells? Does this involve the shutting down of the tumor supressors that would usually prevent healthy cells from overlapping/ occuppying an identical area?

Also, would such technology be applicable for other non-cancerous medical ailments (i.e. ALS,Parkinsons,neurological diseases/disorders, etc)?

Do you see a future relationship emerging with nanotechnology and stem cell research?

posted on Fri, 08/18/2006 - 7:20pm
Ghidewon Arefe's picture
Ghidewon Arefe says:

In answer to your first question, I'm working with researchers at the University of Minnesota's Cancer Center to attach breast cancer antibodies to our silicon quantum dots. So it's not the silicon that is attracted to the cancer cell, but the antibody that we will attach to the silicon. We are working on encapsulating our quantum dots with a material that will make the silicon hydrophillic, that is, a coating that likes to be in water. This will prevent the quantum dots from bunching up and sticking together. This encapsulation will then be spiked with breast cancer targeting antibodies that are already being used for cancer treatment. While we expect most of the silicon quantum dots to end up at the cancer cell, you can always expect to have a few stray particles that work their way through the body before exiting as waste. We are basing our targeting ability simply on the attraction of the antibody to the cancer cell. As the antibody travels through the body, it is eager to connect to a cell. The antibodies we plan on using are very picky and prefer to connect to specific cells, namely breast cells that are cancerous. It's like a person with a picky appetite, even if they are hungry, they can pass by several restaurants until they find just the right one.

In regards to your second question, I'm sure quantum dots could be used as a delivery mechanism for delivering treatments to specific locations in the body that are affected by non-cancerous medical ailments. How that would be done is more a question of biology. I think if we can prove that our silicon quantum dots can target specific locations in the body, than it is a matter of coming up with tretments for those other ailments before we can try targeting those locations.

In response to your third question, my answer is yes and no. Yes, I do see a relationship emerging, but no, not in this country under current legislation.

posted on Tue, 08/22/2006 - 6:16pm