Synthesis And Performance Study Of Nano-MOFs Based On 5,10,15,20-tetrakis (4-carboxyphenyl) Porphyrin Bridging Ligand

Metal-organic frameworks（MOFs）are inorganic-organic hybrid porous materials assembled frommetal ions/ion clusters with organic bridging ligands.In recent years,these novel functional materials have attracted the attention of researchers.Due to the variety of metal ions and organic ligandsa large number of novel metal organic frameworkshave been reported.These materials with high specific surface areas,adjustable pore sizes,abundant in metal-active sites and good biocompatibility,these have exhibited broad application prospects in storage and separation,catalysis,magnetism,and nonlinear optics.In this work,5,10,15,20-tetrakis（4-carboxyphenyl）porphyrins and their derivatives were used as organic ligands and assembled with different metal ions(Cu²⁺,Zr⁴⁺)to construct two metal organic frameworks.Then,the structure and properties of the resulting material were studied.Details are as follows:（Ⅰ）H₂S-Activable MOF Nanoparticle Photosensitizer for Effective Photodynamic Therapy against Cancer with Controllable Singlet-Oxygen ReleaseIn this work,for the first time,a novel mixed-metal-functionalized nanometal-organic frameworks（NMOFs）has been synthesized.This material,as a photosensitizer,can be specifically activated by hydrogen sulfide（H₂S）in a specific tumor microenvironment。On account of another fact that metalated derivatives of PSs can effectively modulate photodynamic activity,we first employed zinc metalated5,10,15,20-tetrakis（4-methoxycarbonylphenyl）porphyrin（ZnTcpp）as a photosensitive bridging ligand to construct a novel single-component MOF NP PS.Then,Cu²⁺ions,an important H₂S-responding site in H₂S fluorescence probes,were selected as metal nodes of the network.As expected,the paramagnetic Cu²⁺ions not only completely quenched the ligand-based fluorescence of the MOF NPs but also significantly minimized the ROS production efficiency of the photosensitive ligand.When H₂S appeared,the Cu²⁺ions were taken out from the MOF nodes.Here,for the first time,we demonstrated that a novel mixed-metal functionalized metal-organic framework nanoparticle（MOF NP）photosensitizer can be activated by a hydrogen sulfide（H₂S）signaling molecule in a specific tumor microenvironment for PDT against cancer withcontrollable singlet-oxygen release in living cells.The effective removal of tumors in vivo further confirmed the satisfactory treatment effect of the MOF NP photosensitizer.（Ⅱ）Study on the Performance of NMOFs Based on Porphyrin Derivatives for Detection of Phosphate Anions in CellsIn this work,using 5,10,15,20-tetrakis（4-carbonylphenyl）porphyrin（H₂Tcpp）as an organic ligand and Zr⁴⁺as metal nodes,a NMOFs fluorescence probe for the detection of phosphate anionshave been presented.This probe exhibited the advantages of high selectivity,high sensitivity and low toxicity.The mechanism of detection is that the porphyrin ligand in the probe forms a metal oxygen cluster through Zr⁴⁺binding.The metal ion Zr can weaken the fluorescence of the porphyrin through coordination;after adding the phosphate anion,the phosphate anion and the probe Zr⁴⁺interacts to form a Zr-O-P bond,and the overall structure of the MOF is not destroyed;due to the interaction between P and Zr,the interaction force between the Zr and the porphyrin ligand is weakened and the fluorescence recovers.In this work,we selected liver cancer cells as a model for biological detection experiments,and achieved selective detection of intracellular phosphate anions.