Dual-enhanced multifunctional molecularly imprinted electrochemical sensor with specificity and signal amplification...

Efficient and sensitive detection of tartrazine content in food is helpful to ensure food quality and consumer health. This study innovatively presented a multifunctional molecularly imprinted polymer (MMIP) combining conductive inorganic nanomaterials and dual function monomers for TZ analysis. The MMIP was fabricated by one-step electrochemical copolymerization of gold nanoparticles (AuNPs), o-phenylenediamine (o-PD), and p-aminobenzoic acid (PABA) on the in-situ synthesized MIL-53(Fe)@MWCNTs nanocomposite. The MIL-53(Fe)@MWCNTs nanocomposite established a stable structure, while the synergistic effect between AuNPs and dual function monomers provided abundant recognition sites and complementary cavities, ensuring high specificity of the sensor and facilitating electron transfer of TZ in the MMIP@Au layer for signal amplification. Under the optimal conditions, the MMIP@Au/MIL-53(Fe)@MWCNTs/GCE sensor demonstrated an extensive linear response (0.2-100 μM) for TZ detection, achieving a low detection limit (11.3 nM) and excellent specificity (imprinting factor = 6.06). Furthermore, the developed sensor demonstrated promising potential for practical applications.