Development of electrochemical 3-MCPD sensor based on molecularly imprinted polymer coating on metal organic framework modified gold electrode

Abstract

3-Chloropropane-1,2-diol (3-MCPD) is formed during the food processing and defined as a potential carcinogen. For this reason practical, effective and economical detection of this substance is crucial. In this work, Fe-MIL-88-metal organic framework (MOF) included electrochemical molecularly imprinted polymer (MIP) based sensor was designed for 3-MCPD detection. Gold screen printed electrodes (AuSPE) were modified with MOF structure and then a MIP layer was formed on the electrode surface via electropolymerization where aniline was used as a monomer and 3-MCPD as a template molecule. In order to improve the response of the prepared sensor, various experimental parameters such as MOF amount, MIP layer thickness, template molecule: monomer ratio, extraction time and rebinding time were optimized. Then, as an analytical characteristic parameter, linear ranges were detected for 3-MCPD in the range of 0.05 μM to 0.5 μM with a limit of detection (LOD) value of 0.43 μM as well as in the range of 0.05 and 0.5 μM with LOD value of 0.01 μM. The specificity of the developed electrochemical sensor was investigated in the presence of interferent reagents and then developed sensor was adapted for 3-MCPD determination in vegetable oil and soy sauce. Lastly the real sample analysis was also validated with gas chromatograpy-mass spectrometry technique which is accepted as gold standard method for 3-MCPD analysis.