It’s been a long time since I was involved in a science fair. When I was seven, I put the microscope I’d just gotten for Christmas on display alongside a “dissected” fish…or maybe it was a frog. By the time I was done with it, I doubt anyone could tell.
Alas, I think first prize that year went to a baking-soda-and-vinegar “volcano.”
Some people are much better at science fairs. Take Kartik Madiraju, a16-year-old Grade 11 student from Montreal’s Central Regional High School. For his science fair project this year, he invented a new source of electrical power that uses naturally occurring magnetic bacteria.
If you’re like me, at this point in the tale you stop and mutter, “Magnetic bacteria? Is there such a thing?”
Indeed there is. Discovered in 1975 by Richard P. Blakemore, magnetic (or, more precisely, magnetotactic) bacteria make tiny iron-containing magnetic particles. Blakemore discovered them when he noticed that some bacteria always moved to same side of his microscope slide, and if he held a magnet near the slide, they always moved toward the north end of the magnet. Apparently the bacteria line up the magnetic particles inside themselves to make one long magnet: turning each bacterium into a tiny living compass.
They don’t use the compass to find north, however; they use it to find down. Magnetotactic bacteria don’t like oxygen, so they always prefer to move toward areas with low or no oxygen. Since they live in the water, that translates into going deeper. Having a built-in compass allows them to find down because in the northern hemisphere geomagnetic north actually lies down and at an angle.
In the southern hemisphere, of course, geomagnetic north points up and at an angle—and the magnetotactic bacteria there are south-seeking rather than north-seeking, and thus still able to head down deeper into their environment to escape oxygen. (At the equator, where geomagnetic north doesn’t point up or down, there’s a mixture of north-seeking and south-seeking magnetotactic bacteria.)
Madiraju had been trying to come up with a science project that could benefit the environment when he ran across an article on magnetotactic bacteria in the science journal Nature. He also knew that if you spin magnets around a coil of wire (or spin a coil of wire inside a magnetic field), a current is generated in the wire. (This is exactly how wind turbines like the ones in the Centennial Wind Power Project in southwestern Saskatchewan generate electricity.)
Madiraju placed the free-floating bacteria inside tiny plastic boxes (each containing about three cubic centimetres of water) which had aluminum strips on two sides to act as electrodes. As the bacteria spun inside the boxes, their magnetic field generated an electric current in the electrodes. By hooking four of these “generators” together in series, Madiraju was able to generate about 750 to 800 millivolts. (There was, of course, a fair bit of trial and error involved.)
Madiraju’s mentor was John Sheppard, a professor in the Department of Bioresource Engineering at Montreal’s McGill University. He admits he “thought the idea was outlandish originally and was one of the most surprised when it worked the very first time.”
Madiraju wonders if the technology could be used in the developing world to develop clean underwater power plants. Sheppard figures more likely uses would be to provide tiny amounts of energy for nanotechnology or biosensors.
Whichever, Madiraju won $3,000 (U.S.) at the Intel International Science and Engineering Fair in Indianapolis last week, where he received the First Place Grand Award in Environmental Sciences/Environmental Engineering.
He wasn’t alone. Adrian Veres of Montreal won $10,000 in prizes and Best in Category and First Prize Grand Awards in Biochemistry “for designing and developing a time and cost-efficient electrical biosensor that can detect infectious disease in bodily fluids such as blood.” Kayla Cornale of Burlington, Ontario, won $4,000 and the First Place Grand Award in Behavioral and Social Sciences/Cognitive Psychology for “Sounds into Syllables™ II; Windows to the World of Childhood Autism,” which uses music to teach autistic children emotions such as happy, sad, afraid and angry. And David Wang of London, Ontario, won $3,000 and the First Place Grand Award in Botany/Other for discovering an alternative treatment for Type 1 diabetes: his project revealed that treated tobacco plants (of all things) have anti-inflammatory properties that can form the foundation of a safe, cost-effective, oral therapy.
Not a baking-soda-and-vinegar volcano in the bunch.
What’s the younger generation coming to, anyway?
