Synthesis Of Zr-based Porphyrin Metal- Organic Frameworks And Used For Fluorescence Probe

The emergence of metal-organic framework(MOFs)materials has attracted the attention of researchers and has become a hot topic in the field of new functional materials.This new material,which is self-assembled from metal ions/clusters and organic ligands,combines the advantages of organic and inorganic materials.Compared with traditional porous materials,MOFs are a new class of hybrid materials with specific topological structure,large specific surface area and adjustable optical properties.Based on these characteristics,it has potential applications in areas including heterogeneous catalysis,gas storage and separation,energy storage,drug delivery,bioimaging systems,and chemical sensing.The MOFs composites composed of matrix and reinforcements have become a new type of material due to their comprehensive properties.The composite material maintains excellent performance of each item,while making up for the limitation that any one of the single items is subjected to in the application,and realizes application in fluorescence detection.It mainly includes the following three parts:(1)First,we synthesized the organic ligand 5,10,15,20-tetrakis(4-carboxyphenyl)porphyrin(TCPP)of MOFs by using methyl p-formylbenzoate.Luminescent porphyrin Zr-MOFs were then prepared,which have a high specific surface area and channels that allow ion diffusion,as well as excellent water stability.It also avoids the reduction of optical properties caused by the aggregation of free ligand TCPP in aqueous solution.Therefore,it can be used as a fluorescence sensor to detect HPO42-in aqueous solution.(2)We synthesized Fe3O4 NPs@PCN-224(RB-PCN)nanocomposites,and characterized the materials using SEM,TEM,EDS,FT-IR and other techniques.The results demonstrated that we successfully compounded the functionalized Fe3O4 NPs with MOFs and linked RBITC via post-modification to ultimately prepare RB-PCN.The material has dual emission fluorescent properties,good dispersibility in aqueous solutions,and exhibits p H-dependent fluorescence changes.It not only responds to a wide range of p H,but also avoids the self-quenching of fluorescence caused by the aggregation of free organic fluorescent molecules,and also because the enrichment effects amplified the fluorescence signal.At the same time,it can also be applied to fluorescence confocal imaging of cells.(3)Based on the previous experiments,we synthesized Ui O-66(OH)2 and PCN-224 to obtain nanocomposites.The material can be used for ultrasensitive ratio fluorescence detection of Cu2+.Ratiometric fluorescent sensors increase the accuracy of detection and enable highly sensitive detection of Cu2+.