Researchers at the University of Melbourne have developed a technique which could increase the sensitivity of magnetic resonance imaging (MRI) for patient diagnosis.

The new technique works by increasing the strength of the magnetic field produced by molecules, and hence increasing their signal when measured by MRI.

The team engineered specific defects in diamond crystals that exert a controlled quantum mechanical influence over the nuclear spins in nearby molecules, including potentially those used in metabolic imaging of brain tumours, making them ‘line up’ (polarise) in a specific orientation.

This hyperpolarised state of nuclear spins is highly ordered and increases the magnetic field that can be detected by techniques like MRI.

It is the first time that this polarisation of molecular nuclei has been shown using such a diamond-based quantum probe.

University of Melbourne School of Physics researcher Lloyd Hollenberg led the research team, with the work published in Nature Communications.

Professor Hollenberg, who is CQC²T Deputy Director and Thomas Baker Chair at the University of Melbourne, said the best MRI scanners in the world are now reaching the maximum magnetic field that can be tolerated by the human body as the technology strives for greater sensitivity.

“The superconducting magnets that produce these fields are also the reason MRI scanners cost millions of dollars, as the magnets need to be kept at cryogenic temperatures,” Professor Hollenberg said.

“Clearly a disruptive approach is needed, so we look to using quantum technology to produce a greater signal intensity of certain molecular targets at the atomic level.”