A novel electrochemiluminescence immunoassay based on highly efficient resonance energy transfer for florfenicol...

A novel competitive mechanism electrochemiluminescence (ECL) immunoassay based on resonance energy transfer was used to detect florfenicol for the first time. In this work, CeO₂@TiO₂ nanocomposite, which was used as a donor, was prepared in sol-gel method and the effective band gap of TiO₂ could be reduced by CeO₂, which promoted the ECL emission of TiO₂ and made the ECL performance of the donor more outstanding. The absorption spectrum of Cu₂S and the ECL emission spectrum of the donor could be highly matched, which ensured the occurrence of electrochemiluminescence resonance energy transfer (ECL-RET). In addition, the snowflake-like structure of cuprous sulfide could load more antibodies. It is worth mentioning that as far as we know, there have been no reports of this material as an ECL receptor before. Furthermore, the ECL-RET system based on this has shown excellent performance in the detection of florfenicol. The proposed immunoassay showed satisfactory sensitivity with a wide linear range from 0.001 to 1000 ng mL^-1 and a low detection limit (0.3 pg mL^-1). Due to the remarkable quenching effect and simple assembly process, the immunoassay is of great practical significance and has reference value for the detection of florfenicol or other biological small molecules.