Electrochemical Detection of Gallic Acid in Green Tea Using Molecularly Imprinted Polymers on TiO2@CNTs Nanocomposite Modified Glassy Carbon Electrode

作者：Fengxian Qin, Tiejun Hu, Lixin You, Wei Chen, Dongshu Jia, Nannan Hu, Weihua Qi · 发表于：International Journal of Electrochemical Science · 年份：2022 · DOI：10.20964/2022.04.06 · 被引用次数：23 · 研究领域：Electrochemical sensors and biosensors、Tea Polyphenols and Effects、Advanced Nanomaterials in Catalysis

The purpose of this study was to use molecularly imprinted polymers on a TiO 2 @CNTs nanocomposite modified glassy carbon electrode (MIP/TiO 2 @CNTs/GCE) to electrochemically determine gallic acid (GA) in green tea. The TiO 2 @CNTs nanocomposite was used to modify the GCE surface using the electrodeposition method and MIP was electropolymerized on the nanocomposite modified GCE. The successful electrodeposition of TiO 2 @CNTs nanocommposite on GCE and the electropolymerization of the MIP layer on the nanocommposite surface were demonstrated by structural investigations using SEM and XRD. The MIP/TiO2@CNTs/GCE was found to be a stable and selective GA electrochemical sensor with a concentration range of 50–700 μM, a sensitivity of 0.02348μA/μM, and a limit of detection (LOD) of 12 nM in electrochemical tests employing DPV experiments. A comparison of the performance of MIP/TiO 2 @CNTs/GCE with that of existing GA electrochemical sensors revealed that the suggested sensor had improved performance, a larger linear range, and an acceptable LOD value for GA detection. The precision and applicability of the proposed electrochemical GA sensor were investigated for determining the level of GA in a prepared real sample of green tea, and the results showed that RSD (2.86% to 4.20%) and recovery (97.65% to 99.30%) of spiked levels in a prepared real sample were acceptable, indicating that MIP/TiO 2 @CNTs/GCE can be considered a reliable GA sensor in food samples.