Fabrication of a molecularly imprinted polymer sensor by self-assembling monolayer/mediator system

Detection of dopamine (DA) by using a molecularly imprinted polymer (MIP) which fabricated by the self-assembling monolayer (SAM)/mediator system was studied. The SAM was made by attaching thioglycolic acid (TGA) on a gold electrode and quercetin (Q) was selected as an electron transfer mediator in this system. Methyl methacrylate (MMA) was polymerized by photopolymerization with the addition of dopamine to form a MIP electrode. The MIP and non-MIP (NMIP) modified electrodes were identified by FTIR and scanning electrochemical microscopy (SECM) approach curves. DA was detected by an amperometric method at a constant potential of 0.45 V and obtained a sensitivity of 0.445 mA cm−2 M−1. The imprinting efficiency approaches infinity due to a non-reactive surface of NMIP. In the interference test, ascorbic acid contributed less than 12% of current response in the coexistence solution with DA and the performance is highly related to the concentration of template added during the fabrication process.