Facile synthesis of enzyme functional metal-organic framework for colorimetric detecting H2O2 and ascorbic acid

摘要

In this work,a metal-organic frameworks material MIL-88 was prepared easily using solvent-thermal method,and was first found to have catalytic activities similar to those of biological enzymes such as catalase and peroxidase.The material was characterized by XRD,SEM,TEM,EDX,Fr-IR techniques and an N2 adsorption method.It exhibited peroxidase-like activity through catalytic oxidation of the peroxidase substrate 3,3',5,5'-tetramethylbenzidine (TMB) in the presence of H2O2,producing a blue-colored solution.Under optimal conditions,the absorbance at 652nm is linearly correlated with the concentration of H2O2 from 2.0 × 10-6 mol/L to 2.03 × 10-5 mol/L (R2 =0.981) with a detection limit of 5.62 × 10 7mol/L(S/N=3).Moreimportantly,a sensitive and selective method forascorbicaciddetection was developed using this material as a catalyst.The analytical method for ascorbic acid detection was observed to have a linear range from 2.57 × 10-6 mol/L to 1.01 × 10-5 mol/L (R2 =0.989) with a detection limit of 1.03 × 10-6 mol/L (S/N =3).This work suggests MOFs have advantages of preparing biomimetic catalysts and extends applications of the functional MOFs in the field of biosensor.