Dual-signal amplification sensing platform based on competitive host-guest cycling recognition process for ultrasensitive detection of thyroglobulin

Dual-signal amplification sensing strategy has been constructed by the competitive host-guest cycling recognition process. Owing to superior photoelectric and photothermal performance of In2Se3 nanoparticles (NPs), the multifunctional probe modified with In2Se3 NPs can generate significantly increased photocurrent and temperature dual signals output during the one-time sensing process. To further achieve signal amplification, with the assistance of supramolecular host-guest recognition between beta-cyclodextrin (beta-CD) and adamantine (ADA), the energy band-matching TiO2 MOF was introduced to construct In2Se3/TiO2 heterojunction that enhance the separation efficiency of photogenerated electron-hole pairs. Interestingly, we found that quantum well-like interface structure (TiO2/In2Se3/TiO2) can be constructed through competitive host-guest cycling recognition process to continuously amplify the signals. The multiple heterostructures can significantly improve light absorption efficiency, not only effectively enhancing the anode photocurrent signal but also generating a robust photothermal response upon the excitation of near-infrared light irradiation. Based on this, the developed dualsignal amplification sensing platform realized ultrasensitive detection of target thyroglobulin (Tg) with linear range from 1.0 x 10_ 5 ng/mL to 1 ng/mL (R2 =0.98) and low detection limit 3.3 x 10_6 ng/mL. The strategy unprecedentedly couples In2Se3 NPs and TiO2 MOF to construct dual-signal amplification interfaces through competitive host-guest cycling recognition process, showing great promise for detection of the target biomarkers in clinical diagnosis.