Abstract
Uric acid is mainly produced from metabolism of purine nucleotide in human body and have several medical importance in human system. It is therefore very imperative to develop a sensitive and accurate method of its detection. This study aimed to develop uric acid biosensor based on polydopamine/polypyrole (PDA/PPY) composite decorated on glassy carbon electrode. The conductive polymer PDA/PPY was electrochemically synthesized and casted on glassy carbon electrode (GCE). The synthesized PDA/PPY was characterized by fourier transform infrared spectroscopy, field emission scanning electron microscopy, electrochemical impedance spectroscopy, energy dispersive x-ray spectroscopy and x-ray photoelectron spectroscopy. PDA/PPY/GCE showed good response towards uric acid with low limit of detection (0.1 mu M, S/N =3), good linearity (0.5-40 mu M) and high sensitivity (2.1 mu A mu Mcm(-2)). It was also found to have stable response for uric acid unaffected by common interferents. Also, when used for uric acid detection in human serum and urine, it showed a good recovery of 90-110%. The developed PDA/PPY composite is proposed as a promising biosensor for uric acid for human health protection.