Such an innovation represents a powerful new tool for medical diagnostics.
"When you walk into a doctor's office, the problem is that it could be one of five or six different pathogens giving you the symptoms," Lee said. "The doctor cannot determine which pathogen you have, so they simply give you a broad-spectrum antibiotic or tell you to go home and get some rest. There clearly is a need for technology that can recognize multiple pathogens simultaneously and at very low levels. It is likely they will be chip-based technologies that are easy to implement in medical environments."
The particles are said to move in a "non-linear" fashion because their motion does not simply increase as the speed of the rotating magnetic field increases.
"There is a surprising effect where at some point the particles stop moving due to their size or what they are attached to, and we can use this effect to our advantage," Lee said. "This effect will allow us to quickly sort through a million particles and say that one's got a certain bacterium on it, that one's got a virus on it, and so on."
The disks are aligned so that their poles point in the same direction. The particles are drawn across the chip as they are attracted by the magnetic fields emanating from the poles and resulting from the external rotating magnetic field.
Different size particles have different "critical frequencies," which means they are moved across the chip by rotating the external magnetic field at specific speeds matching those frequencies.
"So, at a certain frequency, you will see larger particles moving and smaller particles just sort of jitter back and forth," Lee said.
This frequency is higher for larger particles than it is for smaller particles, so speeding up and slowing down the rotation of the external m
|Contact: Emil Venere|