Sensitive and Selective Determination of Uric Acid Using Polyaniline and Iron Composite Film Modified Electrode

We demonstrated a simple and low-cost composite composed of polyaniline and iron composite (PANI-Fe) for the determination uric acid (UA). The successful composite formation was confirmed through scanning electron microscopy, electrochemical impedance spectroscopy and electrochemical methods. The PANI-Fe composite was used to modify the surface of glassy carbon electrode (GCE) and the resulting modified electrode (PANI-Fe/GC) displayed good electrocatalytic activity to the oxidation of UA. The kinetics of the electrocatalysis and effect of scan rate were investigated. The amperometric sensor was developed based on PANI-Fe film modified electrode which delivered quick and sensitive responses to UA. The linear range is 0.05–3860 μM, detection limit is 21.5 nM, and sensitivity is 0.2981 μAμM–1 cm–2. The electrode is highly selective for UA detection. Besides, the electrode has good repeatability and reproducibility. The real-time applicability is verified in human urine samples which displayed recoveries in acceptable range.