Researchers from the National Institute of Standards and Technology (NIST) and University of Colorado Boulder (CU) have developed a low-power microchip that uses a combination of microfluidics and magnetic switches to trap and transport magnetic beads. This chip may have applications in biotechnology and medical diagnostics.
A key innovation in the new chip is the use of magnetic switches like those in a computer random access memory. Conventional microfluidics systems use pumps and valves to move particles and liquids through channels. Magnetic particle transport microchips offer a new approach to microfluidics that generally require continuous power and in some cases cooling to avoid sample damage from excessive heating. The NIST/CU technology eliminates these drawbacks while offering the possibility for random access two-dimensional control and a memory that lasts even with the power off.
The demo chip features two adjacent lines of 12 thin-film magnet switches called spin valves, commonly used as magnetic sensors in read heads of high-density computer disk drives. In this case, however, the spin valves have been optimized for magnetic trapping. Automated spin valve chips might also be used in portable instruments for rapid medical diagnosis or DNA sequencing.
