Research On Application Of Biosensor Based On Metal-organic Frameworks

Metal-organic frameworks(MOFs)are crystalline materials of periodic lattice-like structures with high specific surface area,high porosity and versatility.MOFs are formed by self-assembly of organic ligands and metal ions.MOFs have been widely used in adsorption,sensing and catalysis.In this paper,several metal-organic frameworks were synthesized via simple strategies,and they were used to construct fluorescent biosensors for the analysis and detection of biomarkers.The details are as follows:The first chapter mainly introduced the basic concepts,excellent performance,synthetic methods of MOFs.And its application in sensing,adsorption and catalysis was included.At the same time,it briefly explained the research purpose and contents of this paper.In the second chapter,a fluorescent biosensor to detect uric acid was constructed base on NH2-CuBDC nanosheets.NH2-CuBDC nanosheets has peroxidase mimic activity and fluorescence property.In this experiment,the material can catalyze H2O2 to form hydroxyl radical(-OH)which can oxidize o-phenylenediamine.Due to the inner filter effect,the fluorescence emission of the NH2-CuBDC nanosheets at 425 nm was absorbed by the oxidized o-phenylenediamine.The more H2O2 in system,the higher quench rate of sensor was observed.Based on this principle,a sensor to detect uric acid was fabricated.The concentration of uric acid has a good realitionship with fluorescence intensity of sensor in the range of 10~240 p.M.The limit of detection for uric acid is 3.36?M.In the third chapter,a fluorescent biosensor to detect inorganic pyrophosphatase(PPase)was constructed base on CuBDC nanosheets with peroxidase mimic activity.CuBDC nanosheets can catalyze H2O2 to form-OH which oxidizes terephthalic acid to generate a fluorescent signal.Due to the complexation of Cu2+and pyrophosphate(PPi),the structure of CuBDC nanosheets was destroyed,and the peroxidase mimic activity was lost.While the PPi could be decomposed in the presence of PPase,and CuBDC nanosheets exhibited a mimic enzyme activity that catalyzed the production of OH.Then,terephthalic acid was oxidized and generated a fluorescent signal.This principle was applied to fabricate the biosensor to detect PPase.The concentration of PPase has a good linear relationship with fluorescence intensity of sensor in the range of 0.025?2.5 U/mL.The limit of detection for PPase is 9.27 mU/mL.The biosensor can be used to screen potential inorganic PPase inhibitors.The fourth chapter is based on the rod-shaped CuDHTP nanomaterials to construct fluorescent biosensors for the detection of alkaline phosphatase(ALP).Due to the complexation of Cu2+ and PPi,a part of the organic ligand 2,5-dihydroxyterephthalic acid in the nanomaterials was exposed and generated a fluorescent signal.When ALP was present,it caused decomposition of PPi,and there was no production of the fluorescent signal in the system.Based on this principle,a sensor to detect ALP was fabricated.The concentration of ALP has a good linear relationship with fluorescence intensity of sensor in the range of 0.01?7.5 U/mL.The limit of detection for ALP is 2.67 mU/mL.The biosensor can be used to screen ALP inhibitors.