New Imaging Modality Offers Nanoscale Resolution

Posted in Medical Imaging by Brian Buntz on February 22, 2013
This image symbolically depicts the nanomanipulation of an artificial atom.

A new imaging modality that is similar to MRI but offers a resolution roughly one million fold greater, enabling it to scan individual cells. Developed by scientists at the Institute of Photonic Sciences (ICFO), the CSIC, and Macquarie University in Australia, the technique makes use of artificial atoms and doped diamond nanoparticles to detect extremely weak magnetic fields generated by certain biological molecules.

Normal MRI works be detecting magnetic fields of atomic nucleic within the body that have been excited by a strong electromagnetic field. While conventional MRI is widely used to image the heart, muscles, the brain, and certain cancers, its diagnostic resolution is limited to the millimeter scale.

The researchers have proposed a new technique with a resolution at the nanometer scale, which is sufficient to detect weak magnetic fields from proteins. The breakthrough could enable a new ultra-high-resolution noninvasive diagnostic method that sheds light on the inner workings of individual cells. While a similar resolution has been achieved in the lab, the methods used to accomplish that feat required the use of individual atoms at a temperature near absolute zero.

ICFO professor Romain Quidant led the research project, which enabled the same resolution to be achieved as with individual atoms but at room temperature. The scientists accomplished this by using artificial atoms that were created using a nitrogen impurity within a tiny diamond crystal. The diamond shell stabilized the nitrogen impurity, clearing the way for its use in a biological environment. To manipulate the nanodiamonds, the researchers used laser light as tweezers.
