doi:10.1038/nindia.2013.26 Published online 19 February 2013
Researchers have invented a new drug sensor by modifying glassy carbon paste electrode (GCPE) with a polymer adsorbent and titanium dioxide nanoparticles1. This sensor has successfully detected extremely low levels of three psychiatric drugs — imipramine (IMI), trimipramine (TRI) and desipramine (DES) — in biological and pharmaceutical samples.
The sensor will be handy in detecting these drugs in human blood serum and urine samples.
Overdose of these drugs could result in drowsiness, convulsions, respiratory disorders and even coma. Current techniques to monitor these drugs are time-consuming and require complex steps.
In search of a simple, fast and effective detection technique, the researchers modified GCPE using amberlite-XAD-2 (XAD2), a type of polymer adsorbent and titanium dioxide nanoparticles. This led to formation of the drug sensor. Using this sensor, they then carried out electrochemical experiments to detect the drugs in blood serum and urine samples collected from patients taking them.
On applying negative potentials, the peak current for all the drug molecules increased. The current increase also reflected the accumulation of drug molecules on the sensor's surface. The sensor was very good at detecting the drug molecules even in the presence of interfering agents such as ascorbic acid, uric acid, citric acid, dopamine, glucose, and various ions that are usually found in biological fluids.
"This might be helpful in designing a screen printed electrode for on-site monitoring of these drugs in a wide range of clinical and pharmaceutical samples," says Bankim J. Sanghavi, a co-author of the study.