Ultrasensitive Electrochemical Sensor for Rutin Based on Metal-Organic Framework Cau-1/Mwcnts-Cooh Nanotubes Composites

Rutin, a natural flavonol glycoside, is widely present in plants and foods, such as black tea and wheat tea. The antioxidant and anti-inflammatory effects of flavonoids are well known. In this paper, a new electrochemical rutin sensor was developed, using MWCNTs/CAU-1 as the electrode modification material. The suspension of multi-walled carbon tubes was dropped on the surface of GCE electrode to make MWCNTs/GCE, and CAU-1 was then attached to the electrode surface by electrodeposition. MWCNTs, CAU-1 were characterized using scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). Due to the synergistic effect of CAU-1 and MWCNTs-COOH, the prepared sensor showed ultrasensitive electrochemical response for rutin. Under optimized conditions, the sensor showed a linear relationship between 1.0×10 -9 M ~ 3.0×10 -6 M with the detection limit of 6.7×10 -10 M (S/N=3). The sensor also showed satisfactory stability and accuracy in the detection of real samples.