Iron Porphyrin Metal-organic Frameworks Based Glow Type Chemiluminescence

Chemiluminescence(CL)is a kind of light radiation phenomenon accompanied with chemical reactions.It has the advantages of high sensitivity,easy operation,simple instrument and low cost,and is widely used in clinical diagnosis,food detection and biological analysis.Compared with fluorescence,CL does not need external excitation light source,avoids the interference of self-fluorescence,greatly improves the ratio of signal to noise,and has great potential in the field of biosensor detection,especially in the field of biological imaging analysis.Horseradish peroxidase(HRP)-luminol-H2O2 is the most commonly used enzyme-catalyzed CL system.However,this system has the disadvantages of short CL duration,poor stability of CL intensity,easy inactivation of biological enzymes and complex modification,which greatly limit the application of this CL system in biological imaging analysis.In view of the above problems,this paper prepared iron porphyrin metal-organic framework material(FePorMOF)as a peroxidase mimic,constructed a local tendem reaction involving dual enzymes,and developed a high-intensity and long-term stable glow type CL system.The specific work is as follows: 1.FePorMOF/glucose oxidase based bienzymes glow type CL systemFePorMOF/glucose oxidase nanocomplexes(FePorMOF/GOx)were prepared,and glow type CL system was developed based on local tendem catalysis of bienzymes and local diffusion effect on nanomaterials.In this work,FePorMOF synthesized by hydrothermal method with Zr Cl4 as the metal center and iron porphyrin(Fetcpp)as the ligand has high peroxidase activity.FePorMOF/GOx prepared by electrostatic adsorption of GOx on the surface of FePorMOF possesses good stability.Using FePorMOF/GOx as the catalyst for CL reaction,and luminol-glucose as CL substrates,the FePorMOF/GOx-luminol-glucose system can produce stable high intensity CL emission for 7.5 hours.In this CL system,H2O2 can be generated continuously under the control of enzyme reaction and substrate diffusion,so it can produce long persistent CL emission.In addition,the CL reaction is based on the local tendem catalysis of FePorMOF and GOx,with no limitation on diffusion,so the reaction efficiency is high and the CL intensity is high.The FePorMOF/GOx CL system using glucose as the substrate,which can produce long persistent and intensitive CL emission,has a good application prospect in biological detection and imaging.2.Bienzymes glow type CL system based homogeneous real-time immunoassay methodIn the glow type CL system of FePorMOF and GOx,a homogeneous real-time immunoassay method was developed by using the surface steric effect.In this work,FePorMOF modified with antibody(FePorMOF/Ab1)and GOx were used as the combined catalyst,and luminol-glucose were used as the substrates to construct a glow type CL system.In the presence of target antigen,a sandwiched-immune complex is formed on the surface of FePorMOF,resulting in surface steric hindrance,which prevents the CL substrates from diffusing to the active center of FePorMOF,resulting in the decrease of CL signal.Using alpha fetoprotein(AFP)as the model molecule,this method can detect AFP in homogeneous solution within the range of 0.5-1000 ng/m L in real time.3.Preparation of glow type CL nanoprobeAn integrated CL nanoprobe coated with FePorMOF,GOx and CL substrate L-012 was synthesized to produce intensive CL emission continuously and stably at physiological glucose concentration.The glow type CL nanoprobe has a good application prospect in biological imaging especially in dynamic monitoring.