Supersensitive detection of chloramphenicol with an EIS method based on molecularly imprinted polypyrrole at UiO-66 and CDs modified electrode

Abstract

In this study, a supersensitive electrochemical impedance spectroscopy (EIS) analysis method combined the molecularly imprinted polypyrrole (MIP) which electropolymerized on the composites of zirconium-based metal organic framework (Uio-66) and carbon dots (CDs) modified glassy carbon electrode (GCE) was developed for chloramphenicol (CAP) determination. The integration of Uio-66 and CDs effectively promoted the sensitivity of the proposed MIP senor by improving the surface area and the charge transfer of electrode. By extraction of CAP template, the specific sites were formed on the MIP surface which can rewrap the CAP target molecules. The CAP determination was based on the charge transfer difference (△Rct) before and after the MIP/Uio-66@CDs/GCE rebinding the CAP. The results showed that △Rct responded good linearity to the logarithm of CAP concetration in the range of 0.1 – 100 pmol/L, with a low detection limit of 0.061 pmol/L (S/N = 3), exhibiting high sensitivity and specificity for the determination of CAP.