Shrinky Dinks

Remnember Shrinky Dinks? The acetate sheets you colored, cut out, and then shrunk to thick, clunky plastic in the oven? Did you ever think they'd be useful in a scientific lab? Hah!

In 2006, Michelle Khine arrived at the University of California­'s brand-new Merced campus eager to establish her first lab. She was experimenting with tiny liquid-filled channels in hopes of devising chip-based diagnostic tests, a discipline called microfluidics. The trouble was, the specialized equipment that she previously used to make microfluidic chips cost more than $100,000--money that wasn't immediately available. "I'm a very impatient person," says Khine, now an assistant professor at the University of California, Irvine. "I wanted to figure out how I could set things up really quickly."

Racking her brain for a quick-and-dirty way to make microfluidic devices, Khine remembered her favorite childhood toy: Shrinky Dinks, large sheets of thin plastic that can be colored with paint or ink and then shrunk in a hot oven. "I thought if I could print out the [designs] at a certain resolution and then make them shrink, I could make channels the right size for micro­fluidics," she says.

So she drew out the designs, and when they were shrunk, used them as a mold for her microchannels. While not perfect, the solution has gotten a lot of attention -- both critical and enthusiastic. Now that she's started, of course, people are working on other applications of her "shrinky-dink model". How very cool!