Core-shell-CuFe2O4/PPy nanocomposite enzyme-free sensor for detection of glucose

We demonstrated, for the first time, an enzyme-free sensor for detection of glucose based on chemical oxidative polymerization of pyrrole monomers on the surface of CuFe2O4 nanoparticles (NPs). The morphology and surface property of coating phenomenon of CuFe2O4/PPy core-shell nanoparticles were examined by transmission electron microscopy (TEM), scanning electron microscopy (SEM), and X-ray diffraction (XRD). The electrocatalytic activity of CuFe2O4/PPy toward glucose oxidation was investigated using cyclic voltammetry and chronoamperometry under alkaline conditions. CuFe2O4/PPy core-shells with different shell thickness by varying the amount of pyrrole monomers incorporated were synthesized, and its influence on the morphology and sensing of sensor were also examined. In the amperometric detection of glucose, CuFe2O4/PPy core-shell-modified glassy carbon electrode exhibited limit of detection and sensitivity of 0.1 mu M and 637.76 mu A mM(-1) for low concentrations and 0.47 mu M and 176 mu A mM(-1) for high concentrations of glucose, respectively. It was shown that the presence of pyrrole increased the electronic interaction between NPs and polypyrrole matrices. These excellent performances made CuFe2O4/PPy a potential enzyme-free sensor. The glucose sensor exhibited a linear range response toward glucose in concentration between 20 mu M and 5.6 mM.