Abstract: In this paper, SiO2-coated carbon nanotubes (CNTs/SiO2) were synthesized by sol-gel technique. The vinyl groups were introduced onto the surface of CNTs/SiO2 through chemical modification with γ-methacryloxypropyl trimethoxysilane (MAPS). Through free radical polymerization, CNTs/SiO2-MIPs were successfully obtained by the copolymerization in presence of MAPS-CNTs/SiO2 as support, rutin as template molecule, acrylamide as functional monomer and ethylene glycol dimethacrylate as crosslinker. CNTs/SiO2-MIPs were characterized by infrared spectrometry, thermal gravimetric analysis and scanning electronic microscopy. CNTs/SiO2-MIPs were coated onto glassy carbon electrode to construct an electrochemical sensor. The electrochemical characteristics of CNTs/SiO2-MIPs modified electrode were investigated by cyclic voltammetry and differential pulse voltammetry. The results showed that CNTs/SiO2-MIPs had a good specific adsorption property. DPV peak current response of CNTs/SiO2-MIPs sensor was nearly 2.84 times that of the non-imprinted polymers. In addition, the CNTs/SiO2-MIPs sensor could recognize rutin from its relatively similar molecules of quercetin, naringenin and ascorbic acid. The CNTs/SiO2-MIPs sensor had a wide linear range over rutin concentration range of 0.1-100.0 μmol/L with a detection limit (S/N=3) of 0.032 μmol/L. The CNTs/SiO2-MIPs imprinted sensor was successfully used for the determination of rutin in tablets.
Template and target information: rutin
Author keywords: CNTs, SiO2, surface imprinting, Rutin, Electrochemical sensor