Lessons in Salad Spinning

As part of a global health initiative at Rice University, which asks students to create new ideas and technologies for underdeveloped regions, students Lila Kerr and Lauren Theis set out to find an innovative way to diagnose anemia. The twist was that it had to be low-cost, portable and -- oh yeah -- without any electricity. This was not your usual science project.

So Kerr and Theis started with a salad spinner and developed Sally Centrifuge, which can detect anemia in patients simply by separating heavy blood cells from lightweight plasma. The ratio between the two determines a positive or negative diagnosis. Says Kerr: “We constructed the hand-powered centrifuge out of an everyday salad spinner, essentially a basket that spins within a plastic bowl at the push of a button. We added an insert constructed out of a plastic lid, yogurt container, combs and hot glue.”

In just 20 minutes -- and with a modest $30 price tag -- Sally Centrifuge can test up to 30 individual blood cells at a time. By contrast, the ZIPocrit, a small battery-powered centrifuge that is frequently used today, tests only four samples in a 10-minute time frame. But can a hand-operated device stand up to the power of the Energizer Bunny? “We’ve pumped it for 20 minutes with no problem,” says Theis. “Ten minutes is a breeze.”

With Sally in tow, Kerr, Theis and a Beyond Traditional Borders team traveled this summer to Ecuador, Swaziland and Malawi, completing field tests of their in-class creation. “Ultimately, the hope is that use of our device will allow doctors and nurses in developing countries to better diagnose anemia,” says Kerr. Both positive and negative anemia results often help doctors decipher between malnutrition, HIV/AIDS, malaria and other life-threatening illnesses. Currently, blood samples require overseas testing, something Sally Centrifuge would eliminate by providing speedy, cost-efficient test results.

Plain and simple, this means fewer expenses, quicker results, and most importantly, more lives saved. Sweet!