Construction Of Peroxidase-like Material Based On MOF Structure And Research On Glucose Detection

Nanozyme is a kind of nano-material with enzyme-like activity.It not only has enzymatic properties but also has excellent properties of nano-materials,which has been a research hotspot for a long time.Metal organic frameworks(MOF)is a unique porous nano-material with a periodic network structure,which is self-assembled by inorganic metal elements and organic ligands.There are abundant catalytic sites on MOF,and its structure and inherent characteristics endow the MOF with intrinsic enzyme activity.Multiple MOF-based derivatives could be synthesized to construct nanozymes with high stability and catalytic activity using MOF as a precursor or template.In this research,Cu-MOF nanozyme with peroxidase-like activity was prepared.And then a MOF(Cu-MOF)multi-enzyme simulation system was constructed for immobilizing glucose oxidase(GOx),and rapid glucose detection was realized through a multi-enzyme cascade reaction.The research content of this article is as follows:1.The synthesis and enzymatic properties of Hemin@Cu-MOF:The fixed ratio of BA and BTC was used to construct MOF with crystal defects.In this way,the pore size of MOF could be increased,which was conducive to immobilize glucose oxidase.The results of infrared spectroscopy(IR)and scanning electron microscopy(SEM)showed that the MOF with good dispersion and stable morphology has been successfully synthesized.Hemin@Cu-MOF had good horseradish peroxidase-like activity and could catalyze the formation of TMB into substances with an absorption peak at 652 nm.Under the conditions of pH=4 and 35?,the catalytic activity of the Hemin@Cu-MOF reached the maximum.Steady-state kinetics results showed that Hemin@Cu-MOF obeys the Michaelis-Menten model,and its catalytic mechanism was consistent with natural horseradish peroxidase as a ping-pong mechanism.2.Synthesis and enzymatic properties of Hemin/GOD@Cu-MOF:Hemin/GOD@Cu-MOF was synthesized by physical adsorption method.When the optimal synthesis concentration of glucose oxidase solution was 0.4 mg/ml and the loading time was 1.5 h,the maximum enzyme-catalyzed reaction rate could be reached and the loading capacity was 15.6 mg/g.The glucose oxidase in Hemin/GOD@Cu-MOF catalyzed the production of H₂O₂ from glucose and its own horseradish peroxidase-like activity catalyzed the reaction of the substrate TMB and H₂O₂.Under the conditions of pH=5 and 35?,the catalytic activity of the Hemin/GOD@Cu-MOF reaches the maximum.Compared with free enzymes,Hemin/GOD@Cu-MOF has better properties in terms of thermal stability,pH stability,and ion concentration stability.3.Glucose test:The glucose of beverages was detected using Hemin/GOD@Cu-MOF materials and the results showed that the detection limit was 0.01 mg/m L-0.3mg/m L and the detection time was 20 minutes.The linear equation is y=0.7405x+0.1007,R²=0.99143,and the beverage detection effect is good.