Proposed Technique for Magnetically Separating Blood

PhysicsWeb is reporting that Edward Furlani of the University of Buffalo has proposed a potentially more efficient method for separating the components of blood. Normally, the white blood cells and red blood cells are "separated out from donated blood because a patient may only need one component at any one time." This requires spinning the blood in a centrifuge for up to 20 minutes, which in an emergency situation is an extremely long time. Furlani's proposal seeks to shorten this time by using the fact that in deoxygenated blood red blood cells are paramagnetic and white blood cells are diamagnetic. The separation process would involve sending the blood down a channel embedded with small magnets on one side. The red blood cells would then be attracted to the magnets, while the white blood cells would be repelled. The only apparent catch is the method would not work on oxygenated blood, as oxygen rich red blood cells are diamagnetic and would behave the same way as the white blood cells.

At this point, the system has not been demonstrated in the lab, but Furlani hopes that "his technique could be used to create a portable, low-power and easy-to-manufacture device capable of processing small volumes of blood in emergency situations." In the meantime, a prototype is in the works.