Molecularly imprinted polymer-based electrochemical impedimetric sensors on screen-printed carbon electrodes for the detection of trace cytokine IL-1 beta

In this study, protein-imprinted sensors were electrochemically fabricated on screen-printed carbon electrodes (SPCEs) for the cytokine interleukin-1 beta (IL-1 beta) detection. A double layer comprising poly(o-phenylenediamine) and poly(chromotrope 2R) with a template (i.e., IL-1 beta biomacromolecules) was formed through the cyclic vol-tammetry (CV) technique to modify the molecularly imprinted polymer (MIP) films on the SPCEs. The elec-trochemical sensing properties were investigated via CV and electrochemical impedance spectroscopy to confirm the imprinting effect on the MIP films. The results show that the MIP sensor has a highly sensitive response in the trace IL-1 beta solution (a few pg/mL) with a limit of detection of 0.23 pg/mL and a limit of quantification of 0.78 pg/mL. Furthermore, the MIP sensor showed high selectivity for IL-1 beta adsorption compared to other proteins. In summary, based on binary double layers, the impedance sensing platforms of electropolymerized MIP films show potential application in the practical detection of macromolecular proteins.