Format

Send to

Choose Destination
Nat Med. 2014 Sep;20(9):1069-73. doi: 10.1038/nm.3622. Epub 2014 Aug 31.

Micromagnetic resonance relaxometry for rapid label-free malaria diagnosis.

Author information

1
1] BioSystems &Micromechanics Interdisciplinary Research Group (IRG), Singapore-MIT Alliance for Research and Technology (SMART) Centre, Singapore. [2].
2
1] BioSystems &Micromechanics Interdisciplinary Research Group (IRG), Singapore-MIT Alliance for Research and Technology (SMART) Centre, Singapore. [2] School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore. [3].
3
1] School of Biological Sciences, Nanyang Technological University, Singapore. [2] Infectious Diseases IRG, SMART Centre, Singapore. [3].
4
BioSystems &Micromechanics Interdisciplinary Research Group (IRG), Singapore-MIT Alliance for Research and Technology (SMART) Centre, Singapore.
5
1] School of Biological Sciences, Nanyang Technological University, Singapore. [2] Infectious Diseases IRG, SMART Centre, Singapore.
6
1] BioSystems &Micromechanics Interdisciplinary Research Group (IRG), Singapore-MIT Alliance for Research and Technology (SMART) Centre, Singapore. [2] Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA. [3] Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA.

Abstract

We report a new technique for sensitive, quantitative and rapid detection of Plasmodium spp.-infected red blood cells (RBCs) by means of magnetic resonance relaxometry (MRR). During the intraerythrocytic cycle, malaria parasites metabolize large amounts of cellular hemoglobin and convert it into hemozoin crystallites. We exploit the relatively large paramagnetic susceptibility of these hemozoin particles, which induce substantial changes in the transverse relaxation rate of proton nuclear magnetic resonance of RBCs, to infer the 'parasite load' in blood. Using an inexpensive benchtop 0.5-Tesla MRR system, we show that with minimal sample preparatory steps and without any chemical or immunolabeling, a parasitemia level of fewer than ten parasites per microliter in a volume below 10 μl of whole blood is detected in a few minutes. We demonstrate this method both for cultured Plasmodium falciparum parasites and in vivo with Plasmodium berghei-infected mice.

PMID:
25173428
DOI:
10.1038/nm.3622
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Nature Publishing Group
Loading ...
Support Center