Electrochemiluminescence sensor based on resonance energy transfer for detection of chlortetracycline hydrochloride in food

In this work, a highly sensitive electrochemiluminescence (ECL) sensor for Chlortetracycline hydrochloride (CTC) detection was constructed. The complex of g-C 3 N 4 -chitosan (g-C 3 N 4 @CS) and Pt NPs@MIL-101(Fe) were modified to the electrode. In g-C 3 N 4 -S 2 O 8 2− system, g-C 3 N 4 served as an ECL signal. Synthesized Pt NPs@MIL-101(Fe) acted as a novel coreaction promoter of the system, further enhancing the ECL signal. With the addition of CTC, the ECL signal decreased, and this quenching phenomenon was mainly because of ECL-RET and the related mechanism was studied. Under the best conditions, a strong linear relationship was observed between the change in ECL signal (ΔI) and the logarithm of CTC concentration (lgC CTC ), spanning from 5 × 10 −14 to 5 × 10 −9  mol L −1 . The linear equation was ΔI = 16,817 + 1179.4 lgC CTC with a correlation coefficient of 0.995. The method demonstrates an exceptionally low detection limit of 1.7 × 10 −14  mol L −1 (S/N = 3), making it suitable for real sample analysis.