Studies Of PH Probe And Photodynamic Diagnosis And Treatment Based On Iridium(Ⅲ) And Ruthenium(Ⅱ) Complexes

Transition metal complexes have garnered significant interest in identification detection,medical imaging,and photodynamic diagnosis and treatment due to their exceptional photophysical properties,large Stokes shift,and long lifetime.On the one hand,intracellular p H value serves as a crucial indicator of cell health,and even a slight alteration can result in cell dysfunction,leading to common diseases such as cystic fibrosis,neurodegenerative diseases,and Alzheimer’s disease.Hence,it is crucial to develop probes that can effectively monitor the intracellular microenvironment.On the other hand,photodynamic diagnosis and treatment has the advantages of low cell damage,low drug resistance and strong tissue penetration.In recent years,its clinical application has been increasing.However,the application of typeⅡphotosensitizers in hypoxic conditions is restricted due to their reliance on oxygen.Therefore,the development of new materials for photodynamic diagnosis and treatment in hypoxic environment is of great significance for the treatment of cancer.To address these issues,a set of probes and photosensitivities were developed and synthesized using Iridium（Ⅲ）and Ruthenium（Ⅱ）complexes.This allowed for the monitoring of intracellular p H and photodynamic diagnosis and treatment under hypoxic conditions.The paper is divided into four sections,which cover the following topics:Chapter 1:This paper provides a brief review of the luminescence characteristics,luminescence mechanism,and research status of precious metal phosphorescent complexes.The article emphasizes the application of Iridium（Ⅲ）and Ruthenium（Ⅱ）complexes as phosphorescent molecular probes in the field of analysis and detection,as well as the application of photosensitizing agents in photodynamic diagnosis and treatment.Chapter 2:In this study,a p H phosphor probe（Ru-pba H）was developed using a Ru（Ⅱ）complex as the luminescence center.The probe displayed a light enhancement effect in acidic environments,while showing the opposite effect in alkaline environments.The response sites of the probe were found to be on hydroxyl and imidazole NH.The results indicated that Ru-pba H has the potential to be used for monitoring p H values in cells,as well as in time-resolved luminescence detection and cell imaging.Chapter 3:In order to investigate the impact of various metals on probe properties,a p H phosphorescent probe（Ir-pba H）was synthesized using an Iridium complex with a d⁷ electronic structure as the luminescence center.This probe offers several advantages,including high stability,long luminescence lifetime,and luminescence reversibility,which enables it to monitor p H changes in cells.Chapter 4:In this study,a Ru（Ⅱ）complex（Ru-bam）was synthesized through methylation of the ligand NH in chapter 2.The resulting complex exhibited exceptional detection and photodynamic properties,and displayed a unique response to H₂O₂.Upon oxidation of H₂O₂,the complex released Ru-hy and methyl quinone（QM）as byproducts.Under light conditions,Ru-hy can produce reactive oxygen species,while QM reduces the GSH content in tumor cells,promoting ROS accumulation.The results of phototoxicity tests and evaluation of ROS production in He La cells show that the synergistic effect of both is an important factor in improving the effectiveness of photodynamic diagnosis and treatment.Therefore,Ru-bam is expected to be applied in the integrated diagnosis and treatment of tumor cells.