Magnets used to reduce diagnosis time for infections

New Scientist : Two techniques involving magnets could significantly reduce the time it takesfrom days to hoursto diagnose a fatal infection, writes Jessica Hamzelou for New Scientist. A team at MIT has created a device that uses magnetic resonance to detect a fungus called Candida, which has a 40% mortality rate. Because there are five species of Candida, the team engineered five types of molecular probe, each of which contains a magnetic particle. When the probes are put into blood samples and a magnetic pulse is applied, the water molecules begin to spin; the time it takes for the molecules to return to rest determines whether a species of Candida is present and how much of it there is. A second team at Harvard University has been working to diagnose sepsis. Team members coated magnetic particles with an immune-system protein that binds to the cell walls of pathogens in the blood. The entire cluster can be pulled out using a magnet, and the pathogen can then be identified. “In my opinion both techniques could significantly advance the field of diagnostics.... It’s pretty cool,” said Dirk Kuhlmeier at the Fraunhofer Institute for Cell Therapy and Immunology in Leipzig, Germany.