A three-in-one strategy of molecularly imprinted polymers-based electrochemical SERS for sensitive detection of acetamiprid in vegetables

Selectively trapping analytes in complex matrices to hotspots and performing sensitive detection is an extremely important topic in surface-enhanced Raman spectroscopy (SERS) detection. Herein, a molecularly imprinted polymers-based electrochemical SERS (MIP-EC-SERS) sensor was proposed for detecting acetamiprid (AAP) residue. A polydopamine layer rich in imprinted cavities was fabricated on the surface of AuNPs/ITO, using an electropolymerization process, yielding a SERS substrate modified with MIP (MIP/AuNPs/ITO). Selective capture of AAP by imprinted cavities provided the initial signal enhancement. Subsequently, applying a potential of +0.3 V promoted interactions between AAP and SERS interface, further amplifying the SERS signals. The MIP-EC-SERS sensor achieved a limit of detection down to 3.2 nM and exhibited 13.6 times higher sensitivity than that without applied potential (43.5 nM). Importantly, the practical applicability of the sensor was confirmed by accurately testing AAP in vegetable samples, demonstrating promising application potential for food safety monitoring.