Electrochemical Detection of Dopamine at Poly (o-anisidine)/Silver Nanocomposite Modified Glassy Carbon Electrode

Poly (o-anisidine) and silver nanoparticles based nanocomposite (POA-AgNPs) modified electrode was used for the electrocatalytic detection of dopamine (DA). POA-AgNPs nanocomposite was synthesized via simple and cost-effective chemical oxidative polymerization method. The composite was characterized by x-ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM). The face centred cubic structure of silver and the semi-crystalline nature of poly (o-anisidine) is evident from XRD studies. The formation of polymer matrix-type nanocomposite with the embeddment of silver nanoparticles is determined from HRTEM. The synthesized POA-AgNPs nanocomposite was found to exhibit electrocatalytic activity towards the detection of DA at a potential of +0.45 V. Under the optimal conditions, the modified electrode showed enhanced catalytic current and a linear response was observed in the concentration range of 10.0-140.0 µM with a detection limit of 0.2 µM (S/N=3).The results revealed the potential application of the fabricated sensor for other such biomolecules.