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Wednesday, July 21, 2010

Rocking the Tiny World!

So today was nano-camp day!

Our intrepid group of four (me, Rick, Alex and Nick) have been working to lay the groundwork for this day for a couple of weeks. It was great to finally meet the brave students who had signed up to come to the Photonics center for the day to talk about the science of the very small. Our group of ten students were from all over the Boston area: Brighton, Chelsea, Brookline and Boston itself.
We met the students in the 7th floor chilling area and visited for a while. A number of the students, like Maganow and Yun said that they were considering doing engineering in college. A few said that they were undecided and looking at BU for college. A few were just hoping to do something fun for the day.

That part seemed to work out fine! Professor Altug is about as un-stuffy as you can get - she talked with the kids about what they'd been up to for the past few weeks before introducing them to nano-technology. She started with a version of the Powers of 10.
















If you've never played with the powers of 10 applet, you just have to!!! The universe is just an amazing place, and understanding the sizes of the places in it is the key to understanding a lot of other sorts of things. Prof. Altug rapidly took the kids from oak trees to dust mites to bacteria and other gross stuff. Looks nastier on the SEM!

After taking us through the basics of size, she took us through some other examples of nano-tech in modern life. There are more than I would ever have thought possible before starting this little research project. To begin with, quantum dot nano-particles of gold can be engineered so that they can target cancer cells. Because gold is great at turning certain frequencies of light into heat, it's possible to treat cancer using a laser that targets cancerous cells while leaving the healthy ones intact. Another great example from medicine is in the use of nano-particles in labelling cells of various kinds. With new drugs that can slow the spread of Alzheimer's disease, early detection of illnesses is more important than ever. Nanotech is making it possible for doctors to see diseases before they have a chance to get very far. As I've watched Alzheimer's progress in my own dad, I have seen first hand how great these new treatments are. There's still no cure, but this is a big stride forward. There are so many similar stories; different in their science, but the same in that scientists are unlocking the secrets of some of the world's worst killers, here and in the developing world. The hope of so many researchers is that nano-stuff can be made cheaply - cheap enough that doctors in rural Africa will be able to diagnose and treat as accurately as doctors in Danvers, MA.

So with visions of the micro-world burned into our frontal cortices, Nick, Alex and the others led the group up to our lab where we talked through a few important things, especially some pointers on laser safety. The point of our lab was to give students an idea how researchers use light to study the micro-world, and we started out studying some of our micro-samples under the stereo microscope.

At about 200X, you could see what the diffraction gratings were all about - that's actually connected with the real research that our group is doing. It's about a million times more complex, but the idea is the same, just that our group is working at the nano-scale.

After studying the gratings, the kids checked out what they did to light by focusing a green laser on a diffraction grating. Above, you can see Alex taking some readings on the laser beam spread after it's passed through the grating. Based on the wavelength of the light we used, the students were able to figure out the size of the features on the grating. On the left, Yun and Maganow are getting those numbers, while on the right, my partner Rick is helping out one of his students with the calculations.

After lunch, the students mixed up batches of PDMS gel, and coated their diffraction gratings. We put the samples in a vacuum chamber to get rid of the bubbles, which is important because it helps the goo get down into the tiny grooves in the sample. Then we went for a tour, checked out the clean room and some of the other labs around the building.

At the end of the day, the students pulled off their copies, and checked them out using lasers and microscopes. All I can say about this part is that some of them worked well!

The upward bound experience is a long one, and it's a pretty intense six weeks for the kids. They were great to work with though. Who knows if maybe some day they'll be back in that building helping to make some of the discoveries that'll shape their world.

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