MIT chemists have developed new nanoparticles that can simultaneously perform magnetic resonance imaging (MRI) and fluorescent imaging in living animals. Such particles could help scientists to track specific molecules produced in the body, monitor a tumor’s environment, or determine whether drugs have successfully reached their targets.
The researchers have demonstrated the use of the particles, which carry distinct sensors for fluorescence and MRI, to track vitamin C in mice. Wherever there is a high concentration of vitamin C, the particles show a strong fluorescent signal but little MRI contrast. If there is not much vitamin C, a stronger MRI signal is visible but fluorescence is very weak.
The researchers are now working to enhance the signal differences that they get when the sensor encounters a target molecule such as vitamin C. They have also created nanoparticles carrying the fluorescent agent plus up to three different drugs. This allows them to track whether the nanoparticles are delivered to their targeted locations. These particles could also be used to evaluate the level of oxygen radicals in a patient’s tumor, which can reveal valuable information about how aggressive the tumor is.