A Sensitive Amperometric Sensor for the Determination of Dopamine at Graphene and Bismuth Nanocomposite Film Modified Electrode

摘要

A sensitive amperometric sensor has been developed for the detection of dopamine (DA) at graphenenanosheets (GNS) decorated bismuth nanoparticles (Bi) composite film modified electrode. GNS-Binanocomposite has been prepared by simple solution based method and its successful formation wasconfirmed by scanning electron microcopy and Energy-dispersive X-ray spectroscopy studies. GNS-Binanocomposite film modified glassy carbon electrode (GCE) was fabricated and employed for theelectrocatalysis of dopamine (DA). At GNS-Bi/GCE, well-defined redox couple corresponding to theredox reaction of DA was observed at the formal potential of + 0.195 V with highly enhanced peakcurrents. An amperometric sensor has been fabricated based on the GNS-Bi/GCE, which exhibitedexcellent electrocatalytic ability to the determination of DA. The amperometric sensor presentsoutstanding electrocatalytic parameters such as wide linear range (1 M to 30 M ), high sensitivity-1 -2 (5.304 AM cm ) and low detection limit (0.35 M) . Real sample analysis of the sensor has beenaddressed in pharmaceutical sample which presents appreciable recovery results. The main advantagesof sensor are very simple electrode fabrication procedures, roughed and stable, fast in sensing andhighly reproducible sensor for DA. In addition, the sensor is exhibited high stability and acceptablerepeatability and reproducibility results.