Sensitive Electrochemical Determination of L-Cysteine Using Bismuth Nickelate Nanorods Modified Electrode

摘要

High over potential of the electrochemical oxidation are required for L-cysteine at conventional electrodes owing to the formation of oxide and fouling at the surface of the electrodes. Therefore, it is important to explore novel electrode materials for the sensitive determination of L-cysteine. The electrochemical responses of L-cysteine have been investigated thoroughly at a bismuth nickelate nanorods modified glassy carbon electrode (GCE). The voltammetric studies show that the bismuth nickelate nanorods modified GCE has good electrocatalytic activity toward L-cysteine. There is an irreversible CV peak located at +0.16 V for the electrocatalytic oxidation of L-cysteine in KCI solution. The electrochemical responses of L-cysteine depend on the scan rate, pH value and L-cysteine concentration. The bismuth nickelate nanorods modified GCE shows a widely linear response range of 0.0005-2 mM and low detection limit of 0.087 μM. The bismuth nickelate nanorods modified GCE is a promising candidate as the unit of the electrochemical sensor for the determination of L-cysteine.