An electrochemical sensor for the determination of Luteolin using an alizarin red/carboxylic acid group functionalized carbon nanotube

A novel poly alizarin red (AR) film incorporating carboxylic acid group functionalized multiwall carbon nanotube (f-MWCNT) modified glassy carbon electrode (GCE) was first prepared for the determination of luteolin (Lut). Scanning and transmission electron microscopy were applied for characterization of the surface morphology of the modified electrodes and cyclic voltammetry was used to investigate the electrochemical properties of the proposed electrode towards the oxidation of Lut. Optimization of the experimental parameters was performed with regard to pH, drop-coating volume of f-MWCNT, electro-polymerization cycles of alizarin red, and different potentials of i-t. And the mechanism for Lut detection based on AR/f-MWCNT/GCE was investigated by electrochemical methods. The linearity between the oxidation peak current and the Lut concentration was obtained in the range of 0.5 to 45 μM with a detection limit of 0.17 μM (S/N = 3). In addition, the AR/f-MWCNT/GCE electrode displayed high selectivity, good stability and reproducibility, and also successfully determined Lut in drug samples.