A molecularly imprinted polypyrrole electrochemiluminescence sensor based on a novel zinc-based metal-organic framework and chitosan for determination of enrofloxacin

Nowadays, bacterial resistance caused by the abuse of antibiotics has become a worldwide problem. In this work, a quinolone antibiotic, enrofloxacin (ENR), was rapidly monitored by combining a selective molecular imprinting polymer (MIP) with the electrochemiluminescence (ECL) method. Zn-PTC, a novel zinc-based metal-organic framework (MOF) that has a large specific surface area and ultra-high luminous efficiency, was used as the ECL luminophore. Chitosan (CHIT) was used to contact the specific surface area of molecularly imprinted polymer films and further improved the detection sensitivity. Subsequently, the molecularly imprinted polypyrrole was electropolymerized on the surface of the Zn-PTC and CHIT modified glassy carbon electrode (GCE). The specific sites that could target recombining ENR were shaped on the surface of MIP after extracting the ENR templates. The specific concentrations of ENR could be detected according to the difference in ECL intensity (Delta ECL) between the eluting and rebinding of ENR. After optimization, a good linear response of Delta ECL and a logarithm of specific ENR concentrations could be obtained in the range of 1.0 x 10-12-1.0 x 10-4 mol L-1, with a detection limit of 9.3 x 10-13 mol L-1 (S/N = 3). Notably, this study provided a rapid, convenient, and cheap method for the detection of ENR in actual samples. A schematic illustration of the preparation of a Ppy-MIP/CHIT/Zn-PTC/GCE and the sensing strategy for enrofloxacin.

Automated summary

In this study, a rapid, convenient, and cheap method for detecting enrofloxacin was developed by combining a selective molecular imprinting polymer with the electrochemiluminescence method. The use of a zinc-based metal-organic framework and chitosan improved the detection sensitivity. This method can be widely applied in actual samples.