Hotel California for Bacteria

November 26, 2008

You know how the Eagles song goes: "You can check out any time you like, but you can never leave." Now scientists have developed a similar hotel California for bacteria, only this one is molecular in size (and no stabbing of steely knives).

Kurt Schanze and his team from the Universities of Florida and New Mexico have created microscopic spheres that ensnare bacteria and kill it.

The scientists designed the spheres from polymers that, when exposed to light, produce a form of oxygen that kills bacteria, similar to how bleach kills it. They tested it on a close, but harmless relative of Pseudomonas aeruginosa, a common and lethal bacteria found in hospitals. When exposed to one hour of light, 95 percent of the harmless relative, Pseudomonas aeruginosa PAO1, died. Further testing should determine whether it kills the harmful strain and others like it.

The idea is that the polymer spheres could be used in coatings that are applied to doorknobs, medical devices or other surfaces where diseases often breed.

Photo: Wonderlust Industries

On Deck for the Week of Nov. 24

November 24, 2008

Monday, Nov. 24: Podcast from Clark Boyd. Among lots of things, he'll be talking about how experts are trying to reduce internet scams.

Tuesday, Nov. 25: It's Thanksgiving week and everyone is getting on the road. And you know that means traffic accidents and traffic jams. Jorge Ribas has a video for us about "roads of the future" where cars talk to each other, to the roadside and even to other people's mobile phones—all to make driving safer and smoother.

Wednesday, Nov. 26: Our weekly podcast from Gene Charleton. Venice is sinking. Or rather, the sea around it is rising. The Italian government is spending $4 billion on an engineering project to save it. Listen to what it's all about.

Thursday, Nov. 27: We need to dramatically reduce CO2 in the atmosphere. So, how? For starters, we can stop pumping it into the air. But Kurt Zenz House and Julie Shoemaker of Harvard University think we should be burying it in the ground. They give us their take.

Friday, Nov. 28: Guest blog from David Alexander Ellis. Does Social Stimuli Expand Time? Recently graduated PhD student, David Ellis, tells us about his area of study and what it's like to be starting down the path of research. Read his guest blog.

This Has Nothing to Do with Nanotechnology

November 21, 2008

But what the heck. It's Friday. And this is such a kooky toy that I had to mention it. I wish the sound were a little better. It's so Donkey Kong, ca. 1990. But I guess it matches the graphics. You can get it on Think Geek.

Obama Raises Awareness of Nanotech

November 19, 2008

Okay, it's not Barack, personally, who is raising awareness of nanotech, but his face. John Hart, an assistant professor at the University of Michigan, has created 3-D portraits of the president-elect out of carbon nanotubes, and he's called them "nanobamas." Each one is smaller than a grain of salt and contains about 150 million carbon nanotubes that rise vertically like millions of trees in a dense forest. The growth, when looked down upon from a "bird's-eye" view, resembles the big O.

Hart's Mechanosynthesis Group makes nanostructures and studies how to use them as components in electronics, energy devices and high-performance materials.

The team create the nanobamas by using a laser to create a pattern in a glass plate. Then they shined UV light through the pattern onto a silicon wafer. Next, they grew the carbon nanotubes in the pattern on the wafer.

Hart has a whole gallery of images of nanostructures on his Nanobliss website. Worth checking out.

Photo: Courtesy John Hart

Paper-Thin Speakers from Carbon Nanotubes

November 14, 2008

Researchers in China discovered that if they fed very thin carbon nanotube films particular electric currents, the films would emit loud sounds. A light bulb went on. Or maybe in this case, a bell went off. The researchers realized they could make loudspeakers out a material that was thinner than paper, transparent, flexible, stretchable and magnet-free.

Such a speaker could change not only how we listen to music, but how we hear anything coming from an electronic device, whether it be a cell phone, a laptop, a television. You could imagine a speaker for your mobile phone that you stick into your ear, or turn your shirt pocket into a speaker or a flag (below) that's a speaker or a poster that works as a speaker.

The researchers are reporting their work in an upcoming issue of Nano Letters.

Images courtesy American Chemical Society

Micropscopic Algae Take on BIG Oil

November 11, 2008

Because I used to work as a freelance science writer, I get a lot of science-related materials from institutions, universities and research centers delivered to my door. Press office magazines, for example, or annual reports, etc.

Yesterday I got a research review from the National Renewable Energy Laboratory. There's a lot of great energy-related projects going on at NREL and I'm going pass this little mag along to the Powrtalk guys for blogging fodder. But before I do, I wanted to mention one of my favorite pieces.

It's about using microscope algae to produce a sustainable fuel resource. Algae! Yeah, I've heard of this before. But I didn't actually get how it worked until I read the article. Apparently many species of microalgae naturally produce up to 20 percent of their body weight as fats or oils that can be extracted, sent to a refinery and turned into diesel, jet fuel or even gasoline. Amazing. Here are the other bennies:

• Production of oil from microalgae could be as much as 20 percent higher per acre than it is for other oil seed crops, such as soybeans.
• Microalgae can be grown on land that's not suitable for conventional crops.
• Microalgae can be grown in salty water unfit for conventional ag
• Algae take up carbon dioxide from the atmosphere, just like all plants
• Industrial or power plant air rich in CO2 could be vented over microalgae crops, stimulating them to grow better.

Read more here.

Photo:  Kaz Chiba

Disco Tech Weekly Preview

November 10, 2008

Find your way with these:
11/10: Clark Boyd's Technology podcast
11/11: Puzzle (Bugs on MEMs) 
11/12: Gene Charleton's Engineering Works! podcast
11/13: Top Tech 10: Uses for Carbon Nanotubes
11/14: IM Interviews, News and Q&As with JFK: Inside the Target Car experts

Tiny Backpacks Carry Cancer Drugs

November 07, 2008

Backpack carriers keep get smaller and smaller. Today, it's Kindegarten children. Tomorrow, biological cells. Scientists at the Massachusetts Institute of Technology have figured out a way to attach a little polymer package to two different kinds of immune cells.

Think about it: immune cells naturally zero in on disease and infection. If you could get the cell to carry a drug or some other item that helps doctors diagnose or treat disease, you could go a long way toward curbing or curing those diseases.

The package is made of three parts: a bottom layer designed to attach to the surface of the cell, a middle part that accommodates a payload and a top section designed to attach to other cells, such as cancer cells.

The polymer backpack has a lot of functionality. For example, by filling the middle part with magnetic nanoparticles, Michael Rubner, director of MIT's Center for Materials Science and Engineering, and his team found that they can control a cell's movement using an external magnetic field. The backpack could carry imaging agents that help identify tumors and it could also be filled with chemotherapy agents designed to target tumor cells.

Rubner and his team are reporting their work in the Nov 5 issue of Nano Letters.

Image courtesy American Chemical Society

Bacteria Bots Swim Against the Current

November 04, 2008

Researchers at the E‰cole Polytechnique de Montreal, in Canada, have created nanobots that can be driven and steered remotely using a magnetic resonance imaging machine. The bots are comprised of two parts: a swimming bacteria and a microscopic bead -- kind of a bacteria-borg.

You might think that the bead was the magnetic part, but actually each bacteria naturally contains a chain of magnetic particles inside its body that forms a sort of natural compass. The team, lead by Sylvain Martel, used the MRI machine to change the magnetic field around the swimming bacteria, thereby directing which way the little critter swam. So what's the bead for? It's actually a kind of trailer in which, eventually, the scientists would like to ship a cargo of therapeutic drugs. A specific drug could be directed toward cancerous cells and unloaded at the site.

Photo:  Ecole Polytechnique de Montreal, NanoRobotics Laboratory

You can see a video here. 

Discovery Tech Weekly Preview

November 03, 2008

For the week of Nov 3.

Find your way with these:
11/3: Clark Boyd's Technology podcast
11/4: Puzzle (Bugs on MEMs); Video -- "Is It Future Yet?: Voting Machines," Jorge Ribas checks back in to see what tech advancements have been made for voting machines in this election.
11/5: Gene Charleton's Engineering Works! podcast
11/6: My Take
11/7: IM Interview or a Guest Blog with a student researcher