A simple, sensitive and efficient electrochemical platform based on carbon paste electrode modified with Fe < sub > 3 < /sub > O < sub > 4 < /sub > @MIP and graphene oxide for folic acid determination in different matrices

Talanta. 2021 Jul 1;229:122258. doi: 10.1016/j.talanta.2021.122258. Epub 2021 Mar 15.ABSTRACTA new biomimetic sensor selective to folic acid based on a carbon paste modified with graphene oxide and Fe3O4 nanoparticles coated with molecularly imprinted polymer in the core@shell format (Fe3O4@MIPs) was obtained using the polyol method. The sensing phase was synthesized in a simple way and characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and Brunauer-Emmett-Teller (BET) surface area. In the binding experiments the selective material showed a high adsorption capacity (Q) of 30.4 mg g-1 for MMIP, while the Q value for MNIP (magnetic non-imprinted polymer) was 15.3 mg g-1 both of them following the Langmuir model to the adsorption procedure. After their efficiency was proven, these materials were used as modifiers in the electrochemical sensor (Fe3O4@MIP-GO/CPE). Under optimized conditions using the square-wave adsorptive voltammetry, the proposed sensor exhibited excellent response with a concentration linear range between 2.5 and 48 μmol L-1 and limit of detection of 0.65 μmol L-1 (S/σ = 3). The advantages obtained with the proposed method were high robustness, selectivity, and low cost being these characteristics due to the MIP; highly sensibility due to the high superficial area being the contribution of the magnetite in the core of material; and experimentally versatile since was possible carry out numerous reproductible an...
Source: Talanta - Category: Chemistry Authors: Source Type: research