After six years of research, Professors Jean-François Masson and Joelle Pelletier from the Department of Chemistry at the Université de Montréal have successfully developed the latest cancer detection tool. Their team created a nanodevice that can be used to accurately measure a person’s blood for the commonly used, but toxic cancer treating drug methotrexate—in less than a minute.
When in a patient’s bloodstream, methotrexate blocks dihydrofolate reductase (DHFR) activity. DHFR is an enzyme that is pivotal for DNA synthesis. When the drug blocks the enzyme, cells can no longer divide, diminishing the spread of cancer. Methotrexate, though useful, can also damage the healthy cells of cancer patients and is quite toxic, making it necessary to monitor its concentration to minimize adverse side effects and effectively adjust patient dosage.
“[The drug] has been popularly used for cancer treatment since the [1960s],” Pelletier said. “But the methods for its testing have had slow development.”
Prior to the development of this device, methotrexate detection involved very expensive and complicated platforms that required large groups of personnel. By using Pelletier’s knowledge of the DHFR enzyme and Masson’s specialization in the engineering and design of biomedical instruments and nanomaterials, the six-year project was largely a collaborative exploration. Masson described being driven by an effort to make this process more accessible, simple, and efficient for both patients and medical personnel.
“We joined together based on the resources that were available to us at the time,” Pelletier explained. “We thought, ‘Where could we go with this? How could we make it into something useful?’”
According to Masson, the incorporation of nanomaterials was a large part of what made the project particularly important. For their efficiency and reliability, nanodevices will be a large part of the future of medicine.
The device relies on the operation of Surface Plasmon Resonance (SPR), a system that uses chemical biosensors on a device’s surface—which, in this case, is composed of a thin layer of gold—to detect and compete with methotrexate in the tested blood sample. These gold surface nanoparticles measure the methotrexate concentration by chemically competing with the drug to block the enzyme—which is already present in the blood sample. The gold nanoparticles change color proportionally to the concentration of methotrexate in the tested blood. The test has proved to be both accurate and efficient, taking less than sixty seconds to deliver results identical to those that use more complicated technology.
The successful implications of the project for methotrexate are by no means the end of the road for research of this kind—nor for Pelletier and Masson, who have received additional funding to continue with their project. A device like this one has the potential to reach past just methotrexate-only detection.
The research conducted by Pelletier and Masson has also massively contributed to a better understanding of enzyme-based drug resistances, as well as the ability for this form of chemical technology to detect specific antigens of different antibodies—which would allow for monitoring antibody level in a patient—a useful indicator of the effectiveness and course of treatment for numerous diseases. Furthermore, the chemical sensitivity and accessibility of the device will continue to be improved upon in terms of monitoring progression, course of treatment, and the screening of different diseases.
