Novel nanoceria in situ-derived porphyrin heterostructure enhanced electrochemiluminescent and colorimetric dual-mode detection of tetracycline residue in foods.

Due to serious harm caused by tetracycline (TC) residue to human health, here a multifunctional nanoceria in situ-derived porphyrin heterogeneous framework (CeO2-POF) was innovatively applied to an electrochemiluminescence (ECL) and colorimetric dual-mode sensing platform for TC detection. Concretely, the CeO2-POF fully interprets a "kill three birds with one stone" strategy. Firstly, CeO2-POF integrated ECL luminophore ("bird" one) and co-reaction accelerator ("bird" two), obtaining a 1.6-fold stronger ECL emission than that of tetrakis (4-carboxyphenyl) porphyrin (TCPP) ligand. Secondly, compared with two self-separated signal probes, the single CeO2-POF heterostructure exhibited enhanced ECL and peroxidase-like properties ("bird" three). CeO2-POF showed high catalytic activity against H2O2 and TMB, with color changes monitored via smartphone. Under optimized conditions, the dual-mode sensor for TC achieved a satisfied ECL detection limit of 0.57 pM and a colorimetric detection limit of 0.52 nM. Compared with the commercial ELISA kit, the dual-mode sensing strategy exhibited satisfactory recovery in foods.