Rapidity, sensitivity, and low costs are primary goals in cancer detection. A new method based on magnetoferritin nanoparticles and developed by Kelong Fan, University of Tokyo, Japan, and colleagues, meets all three criteria.

By encapsulating iron nanoparticles inside a recombinant human heavy chain ferritin shell, the researchers created magnetoferritin nanoparticles which permit a specific and sensitive detection of cancerous tissues. While heavy chain ferritin specifically binds to tumor cells via transferring receptor 1, a molecule overexpressed on these cells, the iron oxide core, in the presence of H₂O₂, oxidizes peroxidase substrates to produce insoluble colored precipitates which stain tumor cells.

The researchers demonstrated that this technology can distinguish tumor cells from adjacent healthy cells with 95 % specificity and 98 % sensitivity. Endowed with higher accuracy and repeatability compared with traditional immune-istochemistry techniques, magnetoferritin nanoparticles represent a new promising cancer diagnostic tool.

• Magnetoferritin nanoparticles for targeting and visualizing tumour tissues,
  K. Fan, C. Cao, Y. Pan, D. Lu, D. Yang, J. Feng, L. Song, M. Liang, X. Yan,
  Nature Nanotechnol. 2012.
  DOI: 10.1038/nnano.2012.90