Preparation of zirconia/zinc oxide nanocomposites by sol-gel method for highly sensitive determination of dopamine

Abstract

A novel electrochemical sensor based on ZrO 2 and ZnO hybrid nanocomposites was constructed for the speci c determination of dopamine (DA) with ultra-high sensitivity and selectivity. The structure and electrochemical properties of the composites were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), automatic gas adsorption apparatus and electrochemistry. The results show that in the ZrO 2 /ZnO nanocomposite, ZrO 2 has a large speci c surface area and abundant active site, which can accelerate the oxidation reduction reaction of DA, while ZnO nanomaterials have good conductivity, which can improve the adsorption ability of the sensor to DA. The detection limit of the electrochemical sensor is 94.1 nM in the linear range of 0.5~100 μM. Assays were performed using human serum samples at physiological pH, the recovery rate was 98.5%~101.0%, and the relevant standard deviations were less than 5%. This indicates that the electrochemical sensor is promising for bioanalysis and disease monitoring.