Study On The Electrochemiluminescence Analysis Of Biomolecules In Peroxydisulfate-oxygen System

Biomolecules have great significance in maintaining the normal physiological activities of the living life.Therefor,it is very important to develop a detection method for the monitoring of biomolecules.Electrochemiluminscence（ECL）is a novel detection method which combined the advantages of electrochemical technology and chemiluminscence technology.Generally,ECL refers to the process in which electrochemical species suffer an exergonic electron transfer reaction and form an excited state to emit light.With the advantages of high sensitivity,good controllability and signal-to-noise（S/N）ratio,ECL has been widely used in detection field.After decades of development,much ECL substances have been adopted,among these ECL reagents,peroxydisulfate was attracted amount of attention as its excellent emission ability and simplicity.Thus,to apply peroxydisulfate in detection field would make a great effort in detecting biomolecules.Based on these knowledge,this work designed three signal change strategies to discuss the application of peroxydisulfate in the detection field of biomolecule.The main research work includes three fractions:1.After chemical decorating with L-cysteine（L-Cys）,fullerene(C₆₀)can combine with platinum-palladium nanowires（Pt@Pd NWs）with the help of the induced sulfhydryl group to form a carrier(C₆₀-L-Cys-Pt@Pd NWs).Due to the wonderful carry ability of this metal nanocomposite,a lot of hemin/G-quadruplex and L-alaine dehydrogenase（ALDH）were loaded on the surface of the modified glass carbon electrode.With the satisfied catalysis ability of the adopted materials,a lot of hydrogen peroxide was in situ produced,which can greatly enhance the ECL response of peroxydisulfate.Based on the broader emission window of peroxydisulfate system,the sensitive detection of L-alanine（L-Ala）has been achieved.Scanning electron microscopy（SEM）was applied to monitor the surface states of different materials.Electrochemical impedance spectroscopy（EIS）and cyclic voltammetry（CV）were used to investigate the interfacial changes of the proposed electrodes.ECL technology was employed to explore the ECL properties of the different component in the electrode.In addition,the possible emission mechanism has been discussed.Therefore,this work might open a new view for future development of other ECL biosensors to detect L-Ala.2.A sensitive electrochemiluminecsence（ECL）interface for the detection of glucose has been constructed based on glucose oxidase（GOx）,gold nanoparticles（Au NPs）and nitrogen doped graphene quatum dots（N-GQDs）.In this work,the N-GQDs were used as both an ECL emitter and a reductant to produce Au NPs on their surface（Au NPs-N-GQDs）without using any other reagent.With the chitosan as the stabilizer,the Au NPs-N-GQDs showed a satisfied ECL property,and owning to the specific catalysis of GOx to glucose,the constructed ECL interface possessed a good sensitivity to glucose.Transmission electron microscope（TEM）,energy dispersive X-ray spectroscopy（EDX）,UV-vis spectroscopy（UV-vis）,Raman and ECL methods were used to monitor the surface states,ECL properties and composition of different nanomaterials.The possible emission mechanism of this process has been discussed.The result implies the favorable detection ability of the proposed interface for glucose.3.In this work,a sensitive detection methods for dopamine has been developed based on gold capped copper-β-cyclodextrin nanoparticles（Au@Cu-β-CD NPs）through signal-off strategy quenched by dopamine（DA）.With the help of the desirable carrier fullerene-poly（diallyldimethylammonium chloride）(C₆₀-PDDA),Au@Cu-β-CD NPs was well modified on the glass carbon electrode.Due to the functional groups the DA has,the Au@Cu-β-CD was linked with DA and thus caused to the decrease of ECL signal.Scanning electron microscopy（SEM）,transmission electron microscopy（TEM）,UV-vis spectroscopy and Raman were used to characterize the nanocomposite.The results show the modified GCE has the favorable detection ability for DA.