The technique, called non-linear magnetophoretic separation, works using an array of disks made of cobalt and coated with chromium to prevent corrosion. The disks are regularly, or periodically, spaced on the surface of the silicon chip.
An advantage of the non-linear magnetophoresis technique is that it can be used to simultaneously separate and identify pathogens with a sensitivity up to a million times higher than the "solid phase immunoassays" commonly used today for human diagnostics, said Shang, co-founder of MagSense Life Sciences Inc. and a research scientist at the company, located at the Purdue Research Park. The company is developing a new method to produce the magnetic particles.
The biotechnology industry currently uses magnetic particles to make drugs by separating components in biological materials. The particles attract specific types of molecules, such as proteins and DNA, and then a magnet is used to separate them from the rest of the sample.
The new approach, however, aims to use the particles not for research but for medical diagnostics or possibly to detect biological materials in environmental samples.
The micron-size magnetic particles, which are made of thousands of nanometer-size particles, have a property called superparamagnetism. This means the particles are not magnetic unless they are in a magnetic field, so they can be mixed in a solution without attracting each other and clumping together, which is critical for them to be distributed uniformly throughout the solution. But as soon as the rotating magnetic field is applied, the particles become magnetic, which enables them to be separated.
"What some people are doing very successfully is attaching antibodies that recognize pathogens like bacteria and viruses to these magnetic particles,"
|Contact: Emil Venere|