Magnet technology for accurate malaria diagnosis

In what could offer to be a more reliable way to detect malaria, researchers have devised a magnetic resonance imaging-like (MRI) technique that can do away with potential human error possible in conventional malaria diagnosis.

The new technique uses magnetic resonance relaxometry (MRR), a close cousin of magnetic resonance imaging (MRI), to detect a parasitic waste product in the blood of infected patients.

"It is based on a naturally occurring bio-marker that does not require any bio-chemical processing of samples," said Jongyoon Han, professor at the Massachusetts Institute of Technology in the US.

In conventional malaria diagnosis, after taking a blood sample from a patient, a technician smears the blood across a glass slide, stains it with a special dye, and looks under a microscope for the Plasmodium parasite, which causes the disease.

This approach gives an accurate count of how many parasites are in the blood - an important measure of disease severity - but is not ideal because there is potential for human error.

For the new study, the researchers used a 0.5-tesla magnet, much less expensive and powerful than the 2 or 3-tesla magnets typically required for MRI.

After taking a blood sample and spinning it down to concentrate the red blood cells, the sample analysis took less than a minute.

Only about 10 micro-litres of blood was required, which can be obtained with a finger prick, making the procedure minimally invasive.

"This system can be built at a very low cost, relative to the million-dollar MRI machines used in hospitals," lead author Weng Kung Peng, a research scientist at Singapore-MIT Alliance for Research and Technology noted.

The study appeared in the journal Nature Medicine.