In-situ growth of cerium-based metal organic framework on multi-walled carbon nanotubes for electrochemical detection of gallic acid

Gallic acid (GA) is a valuable polyphenolic compound. GA has a strong antioxidant effect, and its biological properties are anti-inflammatory, anti-histamine, anti-tumor, scavenging free radicals and protecting cardiovascular disease. Therefore, accurate and fast determination of gallic acid content is of great significance to human health. A simple and responsive electrochemical sensor for the detection of gallic acid was constructed by modifying glassy carbon electrodes with the CeMOF/MWCNTs composites synthesized by in situ growth of Ce metal organic framework (CeMOF) on carboxylic acid-functionalized multi-walled carbon nanotubes. The nanomaterials were characterized accurately by X-ray diffraction (XRD), X-ray photoelectron spectroscop (XPS) and scanning electron microscopy (SEM) and so on. Under the optimized conditions, the linear range of the sensor to detect gallic acid is 1.5 μM-200 μM, and the LOD is 0.14 μM (S/N = 3). The sensor can detect gallic acid in tea with good repeatability, stability and anti-interference.