Design And Synthesis Of Temperature-sensitive Polymer-Based Mofs And Fluorescence Detection Applications

Luminescent Meta-organic frameworks(Luminescent Meta-organic frameworks,Luminescent MOFs)are widely used in lighting,display,communication,imaging,fluorescence detection and sensing,etc.The field has broad application prospects.Most of the luminescent MOFs reported in the literature are assembled from rare earth metals and small molecule organic ligands.In recent years,the use of more functional polymer macromolecular ligands instead of small molecule ligands to participate in the assembly of MOFs frameworks has shown excellent performance and broad application prospects.Therefore,this paper uses smart hydrogels as polymer ligands to prepare polymer-based MOFs for fluorescence detection applications.Smart hydrogel is a hydrophilic polymer with a three-dimensional network structure that can respond significantly to small changes or stimuli to the external environment(such as temperature,p H,electricity,light,magnetic fields,specific biomolecules,etc.).How to organically combine the fluorescence detection function of lanthanide metal-organic framework materials with the function of smart hydrogel with environmental responsiveness is the core of this thesis.The main research contents of this paper are as follows:(1)Nano-scale poly-Ln MOFs were prepared by self-assembly using a biomimetic mineralization method,using temperature-sensitive polymers as high molecular organic ligands and Bovine Serum Albumin(BSA)as biotic inducer,and Eu(III)or different proportions of Eu(III)/ Tb(III).The preparation method is simple,fast and mild.Fluorescence spectrum test results show that poly-Ln MOFs have very good optical properties and can be used to identify organic solvents under ultraviolet light.In addition,poly-Ln MOFs show fast response even in the detection of trace amounts of water in mixed solutions of water and organic solvents,so they can be used as water sensors.(2)N-isopropylacrylamide(NIPAAm)and Acrylic acid(AAc)are used as the monomer,and polyethylene glycol macromonomer is used as the crosslinking agent.The photoinitiator is added,and temperature-sensitive hydrogel is prepared viaUV-photopolymerization in aqueous solution.A thermogel-Eu MOFs was prepared by using temperature-sensitive hydrogel as a polymer ligand and self-assembling with Eu(III).Fluorescence spectrum test results show that hydrogel-Eu MOFs display excellent optical properties.Hydrogel-Eu MOFs not only can identify different organic solvents,but also show fast response in trace water detection.At the same time,hydrogel-Eu MOFs also show a rapid response to changes in p H,temperature,and salt aqueous solution.They can be used in sensors and have very important potential value in environmental detection and other fields.