Magnets + laser + water = promising malaria diagnostic

Malaria parasites remain the scourge of Africa and other tropical parts of the developing world. But Case Western Reserve University scientists say the use of magnets might be a low-cost way to diagnose the infection, enabling quicker treatment on a global level.

And now all they need to do is prove it in the field. The New York Times reports that the research team--a student-professor group--is actively looking for investors that could help them test their hand-held malaria detector across Africa. They've even incorporated as the Disease Diagnostic Group so they have an official entity to solicit investments. It is a simple device, essentially a battery-powered box with a laser and a magnetic field.

The pluses here are profound. As the NYT story notes, each device would cost $250 to make. And it's at least 50 cents-per-test cheaper than chemical-based rapid test kits currently used in the field, which are handy, but can also go bad in extreme heat, according to the article. By contrast, the Case Western team says its magnetic laser box diagnostic won't have the same problem and is more accurate.

As of now, the Case Western team has conducted a small number of tests. The New York Times cites one small trial in which their device worked three times as accurately as chemical kits do (on stored blood samples from Papua New Guinea). But they need a much wider test sampling in Africa to prove the viability of their test in the field; hence the quest for investors.

So why magnets? Well it turns out malaria parasites, which eat hemoglobin in red blood cells, can't digest the iron or get rid of it. So as the article explains, they're basically iron rich, and iron can be magnetized. Case Western came up with a way to do this simply, starting with dilution of a drop of blood with water. Their device then generates a magnetic field around the sample, which is illuminated with a laser. A positive result is reflected by the malaria parasites splitting in the blood, via the water. And hemozoin crystals (the iron left in the parasites) line up in the magnetic field.

Case Western's work reflects a broader, increased focus on developing medical devices that can address major health issues in Africa and elsewhere in the developing world. Recently, for example, WHO approved a new nonsurgical circumcision device made of a rubber band and grooved ring designed to help reduce the spread of HIV and AIDS.

- read the NYT story