Sensor to detect painkiller's conspiracy
doi:10.1038/nindia.2011.44 Published online 30 March 2011
Researchers have designed a new sensor that could be used to detect paracetamol-induced elevated levels of epinephrine, a hormone and neurotransmitter in bodily fluids. The sensor was created by modifying the surface of indium tin oxide (ITO) with a multiwalled carbon nanotube and gold nanoparticles.
Epinephrine (EPI) concentration in bodily fluids is considered as a diagnostic symptom of several diseases. Paracetamol (PAR), a widely used painkiller, has also been shown to induce adverse effects by increasing the level of EPI. It is therefore important to monitor the levels of both PAR and EPI in bodily fluids.
Researchers in the past have had difficulty fabricating a suitable sensor for measuring levels of PAR and EPI in bodily fluids. The researchers in this study designed their sensor by attaching gold nanoparticles and a multiwalled carbon nanotube to the surface of an ITO electrode, thereby increasing its surface area.
They then exposed the electrode to human urine samples collected from patients taking PAR. The nanotube and gold nanoparticles facilitated the oxidation of both EPI and PAR through simple electrochemical reactions. During oxidation an increase in current was observed.
The electrode's ability to detect PAR and EPI in the presence of interfering biological agents such as ascorbic acid, uric acid, xanthine and hypoxanthine was also tested. The researchers found that there was no remarkable change in the peak current for up to tenfold increases in interfering agents.
"This indicates that the method can be safely applied to the determination of PAR and EPI in biological fluids," says lead researcher Rajendra N. Goyal.
The authors of this work are from: Department of Chemistry, Indian Institute of Technology Roorkee and Department of Materials Chemistry, Graduate School of Engineering, Kyoto University, Kyoto, Japan.
- Goyal, N. R. et al. Effect of gold nanoparticle attached multi-walled carbon nanotube-layered indium tin oxide in monitoring the effect of paracetamol on the release of epinephrine. Anal. Chim. Acta. doi: 10.1016/j.aca.2011.03.026 (2011)