Thursday, November 19, 2009

what is in your kitty litter

Diatomaceous earth is a common material that we buy in bulk and put into our pool filters and kitty litter. If you thought it was just dirt take a close look. We are mining fossils; an antique algae that looks like a nanomachine.

Friday, November 6, 2009

Nanocars and such

I was asked at dinner tonight about Dr Jim Tour's work on Nanocars by a nonscientist. What I said is that Jim Tour's research on nanocars really highlights how creative minds can envision chemical structures, synthesize them, and then see them in real time because of recent advances in nanotechnology. Dr. Tour takes organic chemistry and makes it interesting by using analogies between nanoscopic molecules and macroscopic things we can see in our everyday life. Nanocars are molecules that have flexible bonds between ring-like structures that can rotate like wheels on a car. Dr. Tour has tested these molecules on various surfaces and used imaging modalities like atomic force microscopy to prove that these molecules do in fact have wheel-like structures that rotate like car tires (he has also synthesized nanoworms or molecules that simply slide across surfaces). What needs to be clarified is that there is not a driver of Dr. Tour's nanocars. These are not nanobots that can be programmed to do a specific function nor can they replicate or be controlled by an outside forces. These nanocars are simply organic molecules that respond to forces like heat and friction to change their conformations (ie. rotate or move) just like any other molecule in the world. It is just that they are synthesized to look like cars and can move across surfaces like roads however they are driven by random thermal energetic forces. They are quite pretty and have an unique ability to engage people in science but just remember, they are molecules that react to physical forces, not magic, not science fiction.

Monday, October 26, 2009

Gold Nanoshells

Why are gold nanoshells for cancer treatment so interesting?

Gold nanoshells are 90- 130 nm particles of silica coated with a thin layer of gold that have unusual optical feature and can potentially be used for cancer therapy and diagnosis. The thin gold coating on the glassy substrate results in a product that can be designed to absorb and scatter light at very specific frequencies. This "tunable" property means by changing the ratio of the silica core to the gold ,gold nanoshells can be manufactured to respond to near infrared light frequencies (>800nm) that are very desirable for therapy and disease detection because near infrared light can pass through human tissue relatively easily.

We have chromophores in our body, like hemoglobin, that like to absorb light in the visible region of the electromagnetic spectrum. So if we can design particles that absorb at the near infrared spectrum (slightly outside of the visible spectra) then these light waves can travel through our tissues without interference from our chemicals that are naturally present in our bodies.

How do nanoshells kill cancer cells?
Called photoablation therapy, this process works because when specific frequency of light is directed at nanoshells, they heat up and the tissue where the nanoshells are located is destroyed via heat. The nanoshells collect around tumors because the blood vessels that are formed to feed the fast growing cancer cells are very abnormal and have a leaky characteristic that let nanoparticles somewhat selectively stay in the the cancerous area.
Because of the surface phenomena that is inherent in metal nanoparticles, gold nanoshells respond to an incident light beam and heat up.

Why do nanoshells heat up?
There are electrons on the surfaces of metals that are free to move around. Because nanoparticles have a lot more surface area exposed than larger particles, the phenomena that occurs at the surface plays a much larger role in determining the physics of the system than if you had a large, bulk chunk of metal. In nanogold, the electrons on the surface of the metal particle can respond to incident light. They basically can vibrate or resonate in frequency with the color of the the light. This is analogous to a child being pushed on a swing. Just like there is an inherent frequency to the push on the swing that will keep the child in motion, light waves can induce a frequency response in the electron on the surface of a metal. This cloud of electrons, often called a plasmon, can swish back and forth across the nanoparticle in response to the incident light. Some of the light energy is transferred in heat and so the particles heat up at specific frequencies. This heat is what kills the cancer cells.

Tuesday, May 12, 2009

NIH challenge grant rabbit-hole

I have not written a blog lately because the NIH released a Science Technology Engineering and Math (STEM) challenge grant 12-OD-102 that was equivalent to saying Drink Me. And then another (12-OD-101) that said Eat Me. The first was to develop a high impact professional development program for science teachers; the other was to show that there was a more effective way for students to learn science. Once someone really smart told me if there seems like there should be a better way, there probably is. Certainly we know a lot about how people learn, yet we aren't teaching that way. This is how I wound up writing two challenge grants, or at least working on them on my spare time.

Released on March 4, 2009,and due on April 27, 2009, the NIH RFA OD-09-003 had a compelling white rabbit to follow: Come up with a unique solution to an important health or education problem that could be tested in a two year period at a price tag of $500,000/year. The challenge areas ranged from bioethics to translational medicine, with this outreach and education solicitation in the middle of the pack.

For those of you who haven't had the opportunity to write an NIH grant lately (it had been a decade for me), this rabbit takes some curious turns (pools of tears, caterpillar advice, etc). Learning that the background section is not allowed, Time 12 font is illegal, and that using the NSF biosketch format could cause your grant to be rejected are just some of the treats at this tea party. Luckily, our university hired extra excellent staff to help us learn how to play croquet with the queen. So now our grant has been submitted and we occasionally get emails that it has passed through another threshold on its journey to be reviewed.

I am not complaining about the experience because we came up with two good ideas that I hope some agency will eventually fund. I am just trying to justify my absence from my blog. I also hope that the reviewers of our grant like the opening: Twas brillig

Tuesday, March 24, 2009

ACS annual meeting Nanoscience: Challenges for the Future

As I pack up to leave Salt Lake City and the 237th American Chemical Society meeting, I wanted to reflect on some of the comments about the future of nanotechnology and nanoeducation.

From the education sessions, it seems clear that K-12 teachers are taking bits and pieces of activities that have been developed through NNI funding. It has to "fit" into their curriculum and that means that it is only adapted if the teachers find it easy to use and it supports and augments the content they are required to teach. For example, 3 week modules on a topic on nanotechnology are unlikely to be used as designed and assessed. The school systems are not flexible enough to allow teachers to implement new curriculum and the testing schedules make it almost impossible for teachers to devote large chunks of time to new content.

The general consensus that I witnessed about undergraduate majors in nanotechnology was that they are too general and students would be better served by majoring on a core science or engineering and then doing nanoscience research in postgraduate studies. There was concern that the true interdisplinary strength of nanoscience research will be watered down if we don't have students with strong foundations in basic sciences. They need to approach nano-projects from different viewpoints. Nanotechnology minors might have more support. Especially if it encourages students to explore a series of courses where they get hands on exposure to some of the tools that are used in nanoscience research but may not be available to undergraduates.

Whitesides commented that nanotechnology as a field is maturing. We have passed beyond the hype and unreasonable expectations of the late 90's and have passed through the following disappointment stage of this decade and are now ready for steady growth - as long as we understand structure-property functions and create materials that have real applications.

Sunday, March 15, 2009

science fair blues

On Friday, I judged 14 chemistry projects at the Houston district science fair. This is a big deal. This was the 50th anniversary of Science and Engineering Fair of Houston. It is a big deal for a student to make it to the judging at the Houston convention center. Advancement to this division means that their project that was one of 30,000 projects entered in the preliminary school/district fair competitions that was chosen to be in this elite group of 1,300 projects from 140 schools. I remember when my daughter's science fair project progressed from from her class science fair, from her school, from her school's region to this large venue - a two day extravaganza.

However, as a judge for over a decade, I can honestly say that the science fair projects, at this level, have never been as dismal as it was on Friday. This was agreed upon by all of the judges in my group. Is it our No Child Left Behind Policy? Is it because the number of students in the Houston Independent School District (HISD) is decreasing while the population of Houston is growing? Are these new students choosing to attend schools outside of HISD? Because of our high stakes testing, I believe that teachers have less class time to devote to science fair projects.

What teachers need to understand is that science fair projects, the posters, and discussions about them, are real. This is really how scientists work. We have poster sessions at meetings where we show our data and defend our findings, seek advice and make connections. Science fair really matters.

Saturday, March 7, 2009

health care

This is outside my normal post, but I think that Health Care is important enough and personal enough to break through ideological constraints. Especially if I think I have something to contribute to the dialogue. Having been pregnant in Austin Texas and delivering a baby there (I drove myself to the hospital) and 2years later, having a baby in Stavanger Norway, I think that it is important that people understand what our idea of "free market" health care has wrought, at least in comparison to one of the most socialized systems in Europe. Our free market approach has created a market for competition in the the most exclusive realms of our health care system. It makes no sense from either an economic or sociological point of view. There are hospitals compteteing to the the most exclusive, up-to-date maternity wards for those few patients who have the luxury of a full American insurance plan.

Meanwhile, the rest of the country is suffering in ignorance and neglect. Strikingly,there are very few prenatal care options for women with out the type of insurance driven health care plan that I had. The average cost of a vaginal delivery in the US is $7,737 ( That does not include prenatal care. This make complete economical insanity because the costs for prenatal care are so much less than the costs for post natal issues (resulting from poor prenatal care).

Having a baby in the US is expensive. I was lucky because although I was in graduate school at the University of Texas at Austin, at a time where they decided to deny all graduate students health care benefits (something to do with having equal benefits with the other UT schools), my husband worked for a larger international company with excellent health care offerings. I was very fortunate because my pregnancy was not normal and involved a lot of extra testing due to issues with my blood, my chemical and x-ray exposures (I was a CHE grad student), and the baby's weight)

Luckily, my first child was completely normal - born on her due date with perfect APGAR scores. And under the American health care system and my husband's international corporations' generous health care insurance, I was in a sleek hospital in a private room with a jacuzzi tub (cant imagine a women in labor using that) but was sent home w/in 24 hours of delivery. Not a lot of care.

In Norway, all of my prenatal care was free. A surprise to me was the lack of paper work> Are you pregnant? was the question, and a simple "yes" entitled you to the best prenatel care in the world (in my opinion). No paperwork, no forms.

My second child was a week late and I was in labor for 2 days. But we still thought it would be easy. IT wasn't. After an emergency C-section, I was in the hospital for 7 days (I could have stayed for 10 but wanted to get home for xmas). During those 7 days, I saw women being taught how to breast feed, how to care for their children, why it was important to vaccinate their children, what the vaccination schedule was, and all kinds of information that the US system hopes is picked up by homes, churches or other groups. Postpartum care was excellen with nurses coming to homes or local well baby checkup centers to ensure that ALL children were vaccinated.

This is important: After seven days of very high tech, personal care, I was told that I could go home. My question was what paperwork to I have to fill out? The answer was none. Just dress your baby and go home. The USA is so overwhelmed with bureaucracy when it comes to health care, we don't know has simple it can be.
Most new moms in Norway are in the hospital for 7 days in a ward room. In someways I was lucky. I had a private room. This had nothing to do with my ability to afford it but rather the complications involving my sons' birth.

My prenatal and postnatal care was better in Norway than in the US under any metric (cost, time, quality - any). So when people say the US has the best health care in the world, I have to wonder about what world they have been living in.

Medical procedures should be based on need not what you can afford. If you have a sick child, you will want the best possible health care. It is like paying for firemen when your house is burning down. Shouldn't we have a health care system that is better than that?

Sunday, March 1, 2009

How to learn to teach nanotechnology in 3 days

There are quite a few 1-3 day teacher workshops on nanotechnology offered around the world. Do they work? Can a middle school or high school teacher learn about these new advances in research AND learn how to effectively integrate it into their classrooms in such a short time? Most teachers who take nanotechnology workshops come away excited about the new applications that they have learned about - quantum dots are beautiful, gold nanoshells have tremendous potential, buckyballs are fun,and who wouldn't be excited about the idea of cheap and easy methods to clean up oil spills or purify contaminated water. However, how much of this content really gets back to the students?

Nanoscience topics are based on quantum mechanics and are challenging to everyone, especially for teachers that may have had excellent scientific training but have been out of college and the research environment for years/decades or for teachers that may have not have strong science backgrounds when they entered teaching. In 3 days, can we teach teachers about how gold nanoshells work via plasmon resonance, how scanning tunneling microscopes (STM) work via electron tunneling, how different chiral structures in nanotubes lead to different properties (metal or semiconductors), or how how the fluorescence of quantum dots is determined by it size because quantum confinement? In 3 days can teachers learn enough about any nanoscience topic to feel confident enough to teach it to their classes? In 3 days, can teachers take this newly acquired knowledge and tailor it to meet the needs of their students, align the requirements of the testing bodies, and are within the limited budgets of their science labs?

There are lots of articles, infomercials, products that claim to help people learn things fast: to read, to paint, to play piano, to manage effectively, to lose weight, to get abs of steel, learn latin. However, the real secret, and it is no secret, is time and practice. How long does it take to learn to be a surgeon, or a concert pianist, or an effective teacher, or great computer programmer?

Peter Norvig, the Director of Research at Google, has the "the best job in the world at the best company in the world" and some interesting essays on line, including Teach Yourself Programming in Ten Years In this article, he discusses how long it takes to really master a subject. He reiterates that people learn by doing, that people learn things over time, that we are always in such a rush to learn or teach something that we don't really accomplish our goals.

I run a teacher internship program and a full semester course CHEM 570 Nanotechnology for Teachers. I don't want to train teachers to be come nanoscience researchers. It takes a minimum of 10 years+ to become a research scientist (4 years undergrad, 4-6 years in graduate school, and then postdoctoral research). It probably takes even longer become an effective high school teacher (and a lot of patience, management skills and emotional maturity). However, if we are going to spend taxpayer money on nanoscience training, I do want to make it effective. I want teachers to learn about new developments in physical science, bring these applications back to their classrooms and translate these findings into lessons where kids have real learning experiences that will help them learn scientific content, motivate them to study/do homework/pay attention in class(this is one of the real issues with American students), perhaps think about careers in science and engineering, and to become adults who are scientifically literate.

It is my belief that we need to rethink these short courses and workshops for teachers in nanotechnology. We need to slow down and engage teachers over an extended period. We need a long term commitment to teaching advanced scientific content and helping teachers use it in their classrooms. Isolated workshops may be engaging and beneficial but it is too separated from the teacher's curriculum. Just in time teaching, ie. teaching the content to the teachers, when they are teaching the subjects in their classes and making it relevant to their teaching goals, will make these programs more effective.

Sunday, February 22, 2009

by any other name

What is nanoscience? Is it different from nanotechnology? Is it chemistry? Many chemists do think that nanoscience is another word for molecular chemistry. However, there are many who would argue that definition (including the physicists, mechanical engineers, chemical engineers, bioengineers working in nanotechnology). Is molecular physics also nanoscience?

Here is the interesting issue about nanoscience and nanotechnology. Kids tend to think it is cool. Or at least they don't associate it with words like chemistry and physics - words that they tend to have very negative feelings about. Scientists and chemists in particular are often the bad guys in movies (e.g. Batman).

What difference does the name make? Do kids seek out nano-related activities over more traditionally named activities? Is this just rebranding of the same old science or is it something new? Can we make nanoscience something different? The physical sciences with real and currently developing applications that can positively impact human and environmental health? Could it be a course that is taught using inquiry based pedagogy w/o a lot of the baggage that other science courses have to carry around (rules and rote memorization)?

Friday, January 23, 2009

Can a new curriculum in nanotechnology improve science education?

I was at a nanotechnology meeting and this question was thrown around. Since American kids, in general, don't like high school chemistry and don't even take physics, could we offer them an alternative science course that was developed by scientists. Would this be better than current science classes and who might take a course in nanotechnology?

Most of the scientists and educators at this NSF sponsored meeting agreed that our high school chemistry curriculum is in a sad state. There is no time for labs and the labs that we have are high stress cookbook affairs. There is little insight into the process of scientific discovery. There are many teachers who don't have the proper background in chemistry (i.e. not chemistry or chemical engineering). We don't have national standards for these well defined courses. and the list goes on.

So what if we developed a really good science class that integrated chemistry and physics and was driven by discovery learning, well trained teachers, and exciting applications and called it nanotechnology? What if we started with what is relevant to kids (their bodies, their gadgets, their environment) rather than significant figures, balancing equations, dropping bowling balls from airplanes? Could this work?

With the high emphasis on 5 point, advanced placement courses in high school, who would take this new class? Maybe it wouldnt attract that population of students, but perhaps it would engage a whole new demographic of students who think that science is just something that old white men do in isolated labs in boring places.

Maybe it could work - the next question is how would could it be implemented.