More resistant than steel, carbon nanotubes are one of the strongest and hardest materials known. Their impressive electrical and thermal properties make them an extremely versatile material. Hollow on the inside and only one-atom thick, they lend themselves to a large variety of potential uses, from tennis rackets and bulletproof vests, to electronic components and energy storage devices. New research shows that they may also hold the potential for revolutionizing medical research with magnetic resonance imaging of individual molecules.

Scientists from ICFO- Institute of Photonic Science, in collaboration with researchers from the Catalan Institute of Nanotechnology (ICN2) and the University of Michigan, have been able to measure weak forces with sensitivity 50 times higher than what has been achieved to date. This significant improvement represents a turning point in measuring very weak forces and opens the door for magnetic resonance imaging at the molecular scale. Dr. Adrian Bachtold, who began this research at the Catalan Institute of Nanotechnology before transferring his research group to ICFO, explains in an article published in Nature Nanotechnology that they were able to prepare the carbon nanotubes to act as probes that vibrate with an intensity proportional to an electrostatic force. With the use of ultra-low-noise electronics, the group led by Bachtold was able to measure the amplitude of the vibration of these nanotubes and thus surmise the intensity of the electrostatic force.

"Carbon nanotubes are similar to guitar strings which vibrate in response to the force applied. However, in the case of our experiment, the forces that cause the vibration are extremely small, similar to the gravitational force created between two people 4500 km apart", explains Bachtold. In the last ten years scientists have made only modest improvements in the sensitivity of the measurement of very weak forces. This new discovery marks a before and after and points to carbon nanotubes playing an important role in future technologies for MRIs of individual molecules.

Conventional magnetic resonance imaging registers the spin of atomic nuclei throughout our bodies which have been previously excited by an external electromagnetic field. Based on the global response of all atoms, it is possible to monitor and diagnose the evolution of certain diseases. However, this conventional diagnostic technique has a resolution of a few millimeters. Smaller objects have an insufficient total number of atoms to allow for the observation of the response signals.

"The results presented are very promising for measuring the force created by each individual atom and consequently its spin. In the future this technique could revolutionize medical imaging" concludes Bachtold.

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ABOUT ICFO:

ICFO-The Institute of Photonic Sciences was created in 2002 by the government of Catalonia and the Technical University of Catalonia. ICFO is a center of research excellence devoted to the sciences and technologies of light with a triple mission: to conduct frontier research, train the next generation of scientists and technologists, and provide knowledge and technology transfer. As part of ICFO's goal to usher advances "made at ICFO" into society, the institute actively promotes the creation of spin-off companies by ICFO researchers.

Research at ICFO targets the forefront of science and technology based on light with programs directed at applications in Health, Renewable Energies, Information Technologies, Security and Industrial processes, among others. The center currently hosts more than 250 researchers and PhD students working in more than 60 different laboratories. All research groups and facilities are located in a dedicated 14.000 m2 building situated in the Mediterranean Technology Park in the metropolitan area of Barcelona.

The high quality of ICFO's research output can be measured in part by the number of papers selected for publication in prestigious journals and also by collaborations with a wide range of companies around the world. The Government of Spain has recognized ICFO's research excellence with the elite Severo Ochoa distinction. Foundation Cellex supports ICFO's research mission by financing the NEST program, making possible many ambitious frontier research projects. ICFO researchers are participating in the multi-million euro Graphene FET Flagship program with a leadership role on the Opto-electronics work package.

Paper: 10.1038/NNANO.2013.97.