Rice expands graphene repertoire with MRI contrast agent
Graphene, the atomically thin sheets of carbon that materials scientists are hoping to use for everything from nanoelectronics and aircraft de-icers to batteries and bone implants, may also find use as contrast agents for magnetic resonance imaging (MRI), according to new research from Rice University. “They have a lot of advantages compared with conventionally available contrast agents,” Rice University researcher Sruthi Radhakrishnan said of the graphene-based quantum dots she has studied for the past two years. “Virtually all of the widely used contrast agents contain toxic metals, but our material has no metal. It’s just carbon, hydrogen, oxygen and fluorine, and in all of our tests so far it has shown no signs of toxicity.” “There are tried-and-true methods for attaching biomarkers to carbon nanoparticles, so one could easily envision using these quantum dots to develop tissue-specific contrast agents,” Ajayan said. “For example, this method could be used to selectively target specific types of cancer or brain lesions caused by Alzheimer’s disease. That kind of specificity isn’t available with today’s contrast agents.” Radhakrishnan said her work began in 2014 after Ajayan’s research team found that adding fluorine to either graphite or graphene caused the materials to show up well on MRI scans. Radhakrishnan said she plans to continue studying the material and hopes to eventually have a hand in proving that it is safe and effective for clinical MRI tests. “I would like to see it applied commercially in clinical ways because it has a lot of advantages compared with conventionally available agents,” she said.