Credit: Juan D. Alfonso
A new device can measure methotrexate levels in a patient’s blood in less than a minute, according to research published in Biosensors and Bioelectronics.
Researchers say this nanoscale device is just as accurate and 10 times less expensive than equipment currently used in hospitals.
It has an optical system that can rapidly gauge the optimal dose of methotrexate a patient needs, thereby reducing the risk of adverse effects.
“While effective, methotrexate is also highly toxic and can damage the healthy cells of patients, hence the importance of closely monitoring the drug’s concentration in the serum of treated individuals to adjust the dosage,” said study author Jean François Masson, PhD, of the University of Montreal in Quebec, Canada.
“The operation of the current [methotrexate monitoring] device is based on a cumbersome, expensive platform that requires experienced personnel because of the many samples that need to be manipulated.”
With this in mind, Dr Masson and his colleagues set out to simplify methotrexate monitoring.
In the course of their research, the team developed and manufactured a miniaturized device that works by surface plasmon resonance. It measures the concentration of serum methotrexate through gold nanoparticles on the surface of a receptacle.
In “competing” with methotrexate to block the enzyme dihydrofolate reductase, the gold nanoparticles change the color of the light detected by the instrument. And the color of the light detected reflects the exact concentration of the drug in the blood sample.
The researchers compared the accuracy of measurements taken with the new device to those taken with equipment used at the Maisonneuve-Rosemont Hospital in Montreal.
“Testing was conclusive,” Dr Masson said. “Not only were the measurements as accurate, but our device took less than 60 seconds to produce results, compared to 30 minutes for current devices.”
Moreover, the comparative tests were performed by lab technicians who were not experienced with surface plasmon resonance and did not encounter major difficulties in operating the new equipment or obtaining the same conclusive results as Dr Masson and his research team.
“In the near future, we can foresee the device in doctors’ offices or even at the bedside, where patients would receive individualized and optimal doses while minimizing the risk of complications,” Dr Masson said.
“While traditional equipment requires an investment of around $100,000, the new mobile device would likely cost 10 times less, around $10,000.”
