A tool to monitor the adverse effects of cancer drug

A new portable device can correctly measure a patient's blood for the effects of methotrexate, a commonly used but potentially toxic cancer drug, in less than a minute.

The standard tools currently used to measure the toxicity level of methotrexate takes around half an hour.

"Testing was conclusive: 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," said lead researcher Jean-Francois Masson from the University of Montreal in Canada.

The new tool is also ten times less expensive than the equipment currently used in hospitals, the researchers claimed.

This nanoscale device has an optical system that can rapidly gauge the optimal dose of methotrexate a patient needs, while minimising the drug's adverse effects.

The device works by a technique called surface plasmon resonance.

Roughly, it measures the concentration of serum (or blood) methotrexate through gold nanoparticles on the surface of a receptacle.

The gold nanoparticles change the colour of the light detected by the instrument. And the colour of the light detected reflects the exact concentration of the drug in the blood sample.

Methotrexate has been used for many years to treat certain cancers, among other diseases, because of its ability to block the enzyme dihydrofolate reductase (DHFR).

"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," Masson concluded.