A simple, sensitive and efficient electrochemical platform based on carbon paste electrode modified with Fe3O4@MIP and graphene oxide for folic acid determination in different matrices

Author(s)

Garcia, Sara Manente ^{[1, 2]} ; Wong, Ademar ^{[1, 2]} ; Khan, Sabir ^{[1, 2]} ; Sotomayor, Maria D. P. T. ^{[1, 2]}

Affiliation

^[1] Natl Inst Alternat Technol Detect Toxicol Evaluat, Araraquara, SP - Brazil

^[2] Sao Paulo State Univ, Chem Inst, UNESP, BR-14801970 Araraquara, SP - Brazil

• Document type: Journal article
• Source: Talanta; v. 229, JUL 1 2021.
• Web of Science Citations: 0

Abstract

A 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 mu mol L-1 and limit of detection of 0.65 mu mol L-1 (S/sigma = 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 analysis only make the renovation of the paste electrode surface by simple polishing. The sensor was applied successfully in pharmaceutical formulation and river water samples with recoveries percentages near 100%. (AU)

• FAPESP's process: 18/09432-4 - Development of electrochemical sensors based on magnetic nanoparticles coated with molecular imprinting polymers for sensitive and selective determination of folic acid and its metabolites in different samples
• Grantee: Sara Manente Garcia
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• FAPESP's process: 19/00677-7 - RADes-MIP - preparation and synthesis of materials for development of rapid analysis devices for monitoring emerging pollutants using highly selective biomimetic polymers based on molecular printing technology
• Grantee: Maria Del Pilar Taboada Sotomayor
• Support Opportunities: Regular Research Grants