Study On Electrochemiluminescence Sensor Based On Novel Nanomaterials For Detecting Drug Molecules

Electrochemiluminescence（ECL）has become an effective technique in the field of modern pharmaceutical analysis.As a powerful analytical technique,ECL method exhibited lots of advantages such as the low background,simple operation and extremely high selectivity.The ECL sensor especially applicable for the systems that are difficult to detect or it contains complex components.In recent years,it has been widely used in clinical analysis,cancer diagnosis,food detection and pharmaceutical analysis.ECL sensor combining the advantages of chemiluminescence and electrochemistry,which can convert the chemical reaction between model analyte and the identification module into series of ECL intensity signals,and realize the qualitative and quantitative detection of the model analyte according to the changing ECL intensity.However,the traditional ECL sensors have been unable to achieve the sensitive and specific detection of model analyte.Therefore,seeking to improve the ECL efficiency and the specificity between recognition module and target molecule have become important parts in the construction of highly sensitive ECL sensors.The main research of this paper is divided into the following parts:Part One:Electrochemiluminescence resonance energy transfer system between ruthenium-based nanosheet and Cd S quantum dots for detection of chlorogenic acidThe study proposed a new strategy for ultrasensitive detection of chlorogenic acid（CGA）by fabricating a resonance energy transfer（RET）sensing platform.Herein,we designed the novel system by introducing ruthenium-based 2D metal-organic framework nanosheets（Ru@Zn-MOF）as energy acceptor and L-cysteine capped Cd S quantum dots（L-Cd S QDs）as energy donor,which exhibited good ECL response.The possible mechanism of the modified electrode surface reaction was discussed.Modifying appropriate of L-Cd S QDs directly on ultrathin MOF nanosheets greatly shorten the electron-transfer distance and reduce energy loss,therefore significantly improving the ECL efficiency.According to the optimal conditions,the constructed sensor for the detection of CGA exhibited a wide linear range from 1.0×10^-10 to 1.0×10^-4 mol·L^-1 with a low detection limit of3.2×10^-11 mol·L^-1.Besides,the prepared sensor demonstrated good stability and highly selective detection of target molecule.Part Two:A novel“signal off-on”electrochemiluminescence sensor based on g-C₃N₄@Cu O for rutin detectionIn this study,a high efficiency“signal off-on”ECL sensor was constructed for ultrasensitive detection of rutin based on carboxylated graphitic carbon nitride（g-C₃N₄）as luminophores（energy donor）,Cu O nanoparticles as quenching probe（energy acceptor）,tri-metallic Au Pt Ag as coreaction accelerator and MIL-101 type MOF as carrier of luminophores.In present platform,Cu O NPs in situ grew on the surface of g-C₃N₄,greatly shorten the distance between energy acceptor and donor pair and greatly enhancing the RET conversion efficiency.In the absence of rutin,Cu O NPs inhibits the ECL intensity of g-C₃N₄（signal off）through RET strategy.Upon the addition of rutin,Cu O NPs could be reduced by rutin and fall off on the surface of g-C₃N₄,the ECL intensity was significantly recovered（signal on）.Under the optimal conditions,the constructed ECL-RET sensor realized the sensitive detection of rutin range from 10 n M to 50μM with the detection limit of 1.7 n M.Furthermore,the as-prepared ECL-RET system exhibits good stability and reproducibility.Part Three:A ratiometric electrochemiluminescence sensor for glutathione detection based on ruthenium derivatives and g-C₃N₄The traditional electrochemiluminescence system is the interaction between different types of luminophores and coreactant to realize signal amplification.However,the intermolecular interaction between them has the drawbacks such as long electron transport distance and high energy loss.In this study,the anodic coreactant trimethylamine（TEA）and the Ru-based luminophores(Ru（dcbpy）₃²⁺)were prepared in the surface of MOF-5.MOF-5could not only be used as carrier to disperse luminophores evenly,but also as the medium to cross-link TEA and Ru（dcbpy）₃²⁺through amide reaction,reducing the electron transport distance and amplifying the anode ECL signal response.On the other hand,using g-C₃N₄ as cathode signal probe and S₂O₈^2-as coreactant,a ratiometric ECL sensor was constructed to achieve highly sensitive detection of glutathione（GSH）.Under the optimal conditions,the detection range of the designed sensor for GSH is 25 p M～50 n M with the detection limit is 8.5 p M.Introducing Ru（dcbpy）₃²⁺/TEA and g-C₃N₄/S₂O₈^2-as anode and cathode signal probe separately,and combining with RET strategy,the sensor provides an effective method for highly sensitive and specific detection of GSH.Part Four:A ratiometric electrochemiluminescence sensor based on luminol derivatives and gold nanoclusters for the epinephrine detectionHerein,a sensitive electrochemiluminescent platform based on N-（4-aminobutyl）-N-ethylisoluminol（ABEI）and glutathione coated gold nanoclusters（GSH-Au NCs）as double luminophores is prepared.Here,GSH-Au NCs were used as working signals,and ABEI were used as reference signals.The crosslinking of GSH-Au NCs and ABEI through amide reaction not only inhibited the solubility of ABEI,but also improved the stability of anode signal response.Ce MOFs were synthesized at room temperature and used as the carrier of double luminescent composites which could improve the dispersion of the sensor interface.The dual signal electrochemiluminescent sensor was used to detect epinephrine（EP）sensitively.As catecholic substances containing phenolic hydroxyl,the presence of EP can quench the cathode signal from GSH-Au NCs.While ABEI,as a reference signal,can further avoid the interference of other components in the detection system.Based on the ratio between the cathode ECL signal and the anode reference signal,a dual signal output ratiometric sensor(E_cathode/E_anode)is designed in this study.Under optimal conditions,the detection range of EP is 30 n M～10μM,and the detection limit is 14 n M.This method provides a more selective and sensitive platform for EP detection and shows excellent practical value in pharmaceutical analysis.