June 23, 2022 | Since its inception in 1977, magnetic resonance imaging (MRI) has been essential in highlighting abnormal tissues and providing detailed images of the human body. Though MRI contributions have been monumental in diagnostics and clinical care, a Colorado State University (CSU) team believes there is more to offer.
Imagine an MRI machine that not only produces images but provides detailed information regarding tumor pH levels or localized temperature changes. Suppose an MRI could extract such highly specific molecular information that it fundamentally changed the way physicians diagnose and treat disease.
What was historically a figment of the imagination might soon become a reality thanks to Joseph Zadrozny, Department of Chemistry Assistant Professor at CSU. With a background in inorganic chemistry and quantum physics, he and his team of students and researchers design metal ion-containing molecules that–alongside magnetic resonance imaging–could detect slight shifts in the human internal environment. “We are living, breathing, talking chemical reactors,” Zadrozny said in a press release. “If you could image that chemistry, it would be really powerful.”
Traditionally, MRIs work by creating a strong magnetic field and sending radio waves to control the alignment and position of atoms–primarily hydrogen–in the body. When the MRI radio waves cease, hydrogen protons transmit radio signals back to the MRI machine as they resume alignment with the magnetic field. These radio signals are then converted to an image.
Simply, MRIs use the magnetic properties of atoms to extract visual information. As published in the Journal of the American Chemical Society (DOI: 10.1021/jacs.2c03115), Zadrozny's team uses cobalt’s magnetic properties to extract chemical information. They design cobalt-based magnetic imaging probes that operate as extremely sensitive chemical thermometers. The team chose cobalt precisely because of its magnetic and temperature-sensitive attributes. “We showed, via nuclear magnetic resonance experiments, that the sensitivity outperformed comparable molecules by orders of magnitude,” said Ökten Üngör, lead postdoctoral researcher.
Cobalt mimics the spin of protons and electrons and their ability to align with magnetic fields. Its temperature sensing abilities make it a strong contender for extracting unprecedented diagnostic information, as many health conditions demonstrate sustained temperature changes before manifesting into full-blown symptoms.
Magnetic Resonance Tumor Detection
If cobalt molecular probes become a successful diagnostic tool, physicians could diagnose, treat, and remove tumors long before existing detection measures recognize their presence. Patients would either receive an injection or ingest the probes before imaging. Then–using temperature shifts to indicate tumor location–in-office thermal ablation procedures would dissolve the tumor without destroying surrounding healthy tissue.
Such MRI functionality offers additional benefits. For example, the team’s designer molecules are safe for human consumption and work at room temperature. Therefore, patients can avoid exposure to dangerous chemicals, harmful machinery, and shockingly cold procedure rooms.
Furthermore, cobalt is amenable to strict control in the lab. “The chemistry around the cobalt atom is highly tunable, and we can control it to a high degree,” Üngör said. “Not only does this work show promise in the medicinal field, but the basic steps and theory may lead to steps forward in the quantum computing realm. We may find even more applications as we continue our research.”
Moving forward, the team hopes to increase the stability and longevity of the cobalt probes, allowing the molecules to remain in the body long enough to be medically beneficial.