The researchers said the magnetic separation technique developed at Duke University's Pratt School of Engineering and Purdue University might lead to new technologies for medical or environmental testing.

For example, the researchers said specially coated magnetic particles designed to attract particular viruses or bacteria might be used in tailored combinations to simultaneously test for multiple infectious pathogens in a blood or water sample.

With that procedure, if a person had been exposed to five viruses, physicians could look for all five viruses simultaneously using just a single drop of blood or water.

Led by Duke Assistant Professor Benjamin Yellen and Purdue Associate Professor Gil Lee, the scientists report their findings in the December issue of the journal Lab on a Chip.