Gold nanoparticles decorated silicate sol-gel matrix embedded reduced graphene oxide and manganese ferrite nanocomposite-materials-modified electrode for glucose sensor application

Abstract

Gold nanoparticles decorated on silicate sol-gel matrix embedded manganese ferrite (MnFe 2 O 4 )reduced graphene oxide (rGO) nanocomposites were synthesized through a facile chemical method. The prepared samples were characterized by using powder X-ray diffraction (XRD), UV-vis absorption spectroscopy (UV-VIS), energy-dispersive X-ray spectroscopy (EDX), high-resolution transmission electron microscopy (HRTEM) and selected area electron diffraction (SAED) analyses. The Au nanostructures on rGO-MnFe 2 O 4 improved the electrocatalytic activity of the rGO-MnFe 2 O 4 @Au composite-materials-modified electrodes towards glucose oxidation. Cyclic voltammetry and amperometric methods were used to evaluate the electrocatalytic activity of the rGO-MnFe 2 O 4 @Au modified electrodes towards glucose oxidation in 0.1 M NaOH at a less-positive potential (0.2 V) in the absence of any enzyme or redox mediator. The nanocompositemodified electrode (GCE/EDAS/rGO-MnFe 2 O 4 @Au) was successfully used for the amperometric sensing of glucose and the experimental detection limit of 10 μM glucose was observed. The common interfering agents did not interfere with the detection of glucose. The present sensor showed good stability, reproducibility, and selectivity. The nanocomposite-modified electrode was successfully used for the determination of glucose in the urine sample.

An electrochemical sensor based on molecularly imprinted polydopamine coated on reduced graphene oxide for selective detection of ornidazole

“…The sensitivity of electrochemical MIP sensors could be improved by using various nanomaterials that enhance the effective surface area of the electrode, rate of electron transfer, and hence electro-catalytic activity. For this purpose, reduced graphene oxide (RGO) could be used as nanomaterials instead of graphene because of the low solubility, the lack of groups promoting chemical interactions, and the limited number of active sites of graphene [27][28][29][30]. The restoration of a graphitic network of sp 2 bonds during the reduction process of GO provides excellent conductivity, high surface area, and stability to RGO.…”