Coordination-induced electrochemiluminescence of Zr-based metal-organic frameworks combined with an energy resonance transfer for sensitive analysis of acetamidine

The development of a simple and accurate method for the detection of acetamidine (ACE) is vital for food and environmental safety. Herein, combined with electrochemiluminescence resonance energy transfer (ECL-RET) and DNA cyclic reaction signal amplification, a highly sensitive electrochemiluminescence (ECL) sensor was fabricated for detecting ACE using Zr-TBAPy-MOFs (Zr-MOFs) as the emitters, which possessed coordination-induced electrochemiluminescence (CIECL) properties. The rigid structure of Zr-MOFs restricted intramolecular motion (RIM), inhibiting non-radiative transitions and significantly enhancing ECL efficiency compared with monomers and aggregates of 1,3,6,8- tetrakis (p-benzoic acid) pyrene (H₄TBAPy). In the presence of the target ACE, the aptamer (Apt) dissociated from double-stranded DNA (Apt/S) and triggered a cascade of DNA reactions. This led to the immobilization of a double-strand labeled by tetramethylrhodamine (TAMRA) onto the electrode, facilitating ECL-RET and subsequent quenching the ECL signal. Observably, as ACE concentration increased, a linear decrease in ECL signal was observed within the detection range of 0.05 ng/mL to 100.0 ng/mL, and an impressive detection limit was 6.0 pg/mL. Our developed biosensor presented a novel approach for successful implementation of ECL-RET in ACE detection.