Researchers came up with a way to diagnose malaria using magnetic fields.
In conventional methods a blood sample enhanced with dye is looked at under a microscope to determine the number of parasites present, but this method is susceptible to human error, the Massachusetts Institute of Technology reported.
Researchers recently discovered magnetic resonance relaxometry (MRR) could detect the amount of parasite waste present in the blood.
"There is real potential to make this into a field-deployable system, especially since you don't need any kind of labels or dye. It's based on a naturally occurring biomarker that does not require any biochemical processing of samples" said Jongyoon Han, a professor of electrical engineering and biological engineering at MIT.
The new SMART system looks for parasitic waste called hemozoin. When parasites infect red blood cells they feed on the nutrient-rich hemoglobin; when hemoglobin breaks down it releases potentially-toxic iron which is then converted into hemozoin (a weakly paramagnetic crystallite).
The crystals interfere with the normal magnetic spins of hydrogen atoms; when exposed to powerful magnetic fields hydrogen atoms align their spins in the same direction. If a smaller field interferes with the atoms they should all change their spins in a uniform direction, but if hemozoin is present the synchrony is disrupted.
The method is relatively inexpensive and can be conducted in under a minute.
"This system can be built at a very low cost, relative to the million-dollar MRI machines used in a hospital," said lead author is Weng Kung Peng, a research scientist at SMART.. "Furthermore, since this technique does not rely on expensive labeling with chemical reagents, we are able to get each diagnostic test done at a cost of less than 10 cents."
The findings were published Aug. 31 issue in the journal Nature Medicine.
