Electrogenerated Chemiluminescence Coupled with Molecularly Imprinted Polymer for Sensitive and Selective Detection...

A simple and efficient approach that combined electrogenerated chemiluminescence (ECL) and molecularly imprinted polymers (MIPs) for selective and sensitive detection of the hallucinogenic drug N,N-dimethyltryptamine (DMT) was developed. ECL, one of the most sensitive analytical techniques for ultratrace analyte detection, offers the advantage of light-free spectroscopic analysis initiated by electrochemistry. MIPs, on the other hand, provide specific binding sites, allowing the target analyte to become selectively imprinted within the polymer matrix. In this study, an ECL coupled-MIP sensor was fabricated using para-aminobenzoic acid (p-ABA) as the monomer and DMT as the template molecule. The MIP was electropolymerized onto a glassy carbon electrode coated with a Nafion film entrapping [Ru(bpy)₃]²⁺ species. Following elution, the imprinted sites were reoccupied by DMT, generating ECL signals in a phosphate buffered solution during anodic potential scanning. The ECL-MIP sensor demonstrated a wide dynamic range for DMT detection, from 0.5 to 300 μM, with an estimated detection limit of 0.5-1.0 μM (S/N = 3). The sensor's reproducibility, stability, and selectivity were also evaluated. Finally, density functional theory was employed to investigate the structure-property relationship of the p-ABA-DMT interaction. This work demonstrated the potential of ECL coupled with MIP technology for identifying structurally related molecules, achieving enhanced selectivity with a simple and cost-effective design.