Studies Of Electrochemiluminescence Sensors Based On Porous Materials

As a novel analytical technique,electrochemiluminescence（ECL）is regarded as an appropriate alternative compared with traditional sensor technology.ECL,an effective strategy combing electrochemistry with chemiluminescence,has been considered a promising method for constructing different biosensors,owing to its zero background,ability to respond in real time,regulated potential,and so on.Considering the requirements for biosensor sensitivity and selectivity,the development of ultra-sensitive and specifically selective ECL sensors is of profound importance for clinical medicine,environmental monitoring,food safety,and other fields.In this work,we construct ECL sensors that specifically respond to different functional molecules（antigens,bioactive molecules,and food active ingredients）using metal-organic frameworks（MOFs）,covalent organic frameworks（COFs）,and porous silica materials（Si O₂）as matrices,respectively.This work has significantly promoted the application of porous materials in the field of sensing.Details of the work are as follows:1.A sandwich ECL immunosensor based on gold nanoclusters（Au NCs）and MOF[Cu₃（HHTP）₂]was constructed to detect CEA.Immobilization of Au NCs as an ECL luminescence probe on the electrode surface to produce cathodic ECL in K₂S₂O₈ solution acting as the co-reactant to boost the ECL.Based on the specific binding between antibody-antigen,antibody-linked Cu₃（HHTP）₂ was captured to the electrode surface to annihilate the ECL signal of Au NCs.The as-prepared sensor showed excellent CEA detection performance in the concentration range of 0.005 to 100 ng/m L,with a detection limit of 0.81 pg/m L.2.A strategy was developed for preparing cyanidin-3-O-glucoside（C3G）imprinted Ru@Si O₂-COF MINs,and it was applied as an adsorbent to the separation and purification of C3G in actual samples.The as-constructed ECL sensor realized the adsorption and detection of C3G throughπ-π*interaction and hydrogen bonding.In addition,captured in the imprinted cavity,C3G could efficiently quench the ECL of Ru@Si O₂ due to the overlap between the two spectra.As a result,this sensor provided a highly sensitive readout of the C3G content in solution.Under optimal conditions,the sensor detected C3G in the range of 0.005-40 ng/m L with a detection limit of 1.84 pg/m L.3.An ECL sensor based on Ce O₂-Au-Luminol@Si O₂@PNIPAM thermosensitive polymer was constructed to monitor the level of H₂O₂.Ce O₂,an electroactive material,dramatically enhanced the ECL of Luminol and H₂O₂.Self-enhanced ECL emitter was prepared by combining Au-Luminol with Ce O₂.The surface modified porous Si O₂ can improve the ECL stability.The temperature-sensitive polymer PNIPAM was generated on the surface of Si O₂.With the change of the critical solution temperature（LCST）,PNIPAM could form an"on"or"off"state,which could be used as a targeting device to control the release of H₂O₂.The constructed Ce O₂-Au-Luminol@Si O₂@PNIPAM thermosensitive ECL sensor had a detection range of 0.005-1 m M and a detection limit of 80 p M for H₂O₂.