Dancing beads could hold key to faster, more flexible medical testing

Chip technology could be used to develop faster, more flexible medical testing that requires only a minute fluid sample, according to researchers at the Massachusetts Institute of Technology.

The research, published in the journal Lab on a Chip, draws on the concept that balls moving through fluid lose speed as they grow larger.

Graduate student Elizabeth Rapoport and assistant professor Geoffrey Beachof MIT's Department of Materials Science and Engineering so far have developed the concept, though they've not used it in tests on biological samples.

They used microscopic magnetic beads that can be coated with biomolecules such as antibodies that cause them to bind to specific proteins or cells, reports MIT News.

Building upon their previous research in which they had these beads moving along magnetic tracks, the researchers set the beats oscillating by creating a variable series of strong magnetic fields, known as magnetic domain walls, which also act as sensors, according to Genetic Engineering and Biotechnology News.

The rate of oscillation can be measured as the beads' size grows, offering an almost instantaneous reading of whether the bead has grown through attachment to a target biomolecule, rather than requiring the sample to be sent to a lab for analysis.

An added plus: the material can be reused by simply flushing it out. "You'd just use it, wash it off, and use it again," Rapoport told MIT News. Their next step is to create an operational sensing device.

The work is the latest example of biomedical research drawing on principles used in computing. A wireless, handheld blood-analysis system developed at the University of Rhode Island, too, requires only a drop for its "lab-on-a-chip technology."

Stanford researchers have teamed up with Intel on chip technology to better understand protein interactions, which holds promise to improve diagnosis of multiple diseases and to quickly determine the most effective drug for a particular patient.

To learn more:
- read the abstract
- here's the MIT News article
- check out the story at Genetic Engineering and Biotechnology News