Application Of UiO-67-supported Metal Carbonyl Complexes In Gas Therapy And Magnetic Resonance Imaging

Malignant tumors are one of the major diseases that seriously endanger human health in the world today.Since the 1970s,the incidence and mortality of malignant tumors in my country have been on the rise.However,the current conventional cancer treatment methods have limitations such as greater invasiveness,low specificity,expensive treatment costs,and long treatment cycles.Therefore,new cancer treatment methods are in full swing.The rapid development of nanotechnology has brought new ideas for cancer treatment.Nanoparticles are used to load small-molecule drugs and deliver them precisely to the depths of tumor lesions,so as to achieve targeted cancer therapy.Due to the good high permeability and long retention effect（EPR）of nanoparticles in solid tumors,the efficient utilization of tumor drugs can be achieved,thereby reducing the side effects of treatment.Gas therapy has been widely used in tumor treatment,such as carbon monoxide（CO）,hydrogen sulfide（H₂S）and hydrogen（H₂）,etc.The use of gas therapy can alleviate the common problem of tumor drug resistance in chemotherapy,improve tumor drugs and reactive oxygen species（ROS）treatment effect.Magnetic resonance imaging is the latest medical imaging technology using the principle of nuclear magnetic resonance,and it has become an effective weapon for early screening of tumor diseases and cardiovascular and cerebrovascular diseases.Therefore,the synthesis of polymer nanoparticles with enhanced imaging effect as the carrier of small molecule drugs can realize the integration of tumor diagnosis and treatment.In this paper,we first synthesized the metal-organic framework Ui O-67 by solvothermal method,continued to support manganese pentacarbonyl bromide through coordination,and further improved the water solubility by using phosphoric acid PEG to synthesize Ui O-67 supported by metal carbonyl complexes.Nanoparticles（Ui O-67-Mn（CO）₃Br-PEG and Ui O-67-Fe（CO）₂I₂-PEG）,the synthesized nanoparticles can convert H₂O₂into hydroxyl groups while generating CO gas after xenon lamp irradiation Free radical（·OH）,we discussed the reaction process of the solution in detail,and the excellent properties of the experimental results showed that Ui O-67 supported carbonyl metal complex nanoparticles are expected to play a role in the combined treatment of CO gas therapy and chemodynamic therapy effect.We also found that the CO gas release process is actually the process of removing the carbonyl group of the strong ligand,which will cause the Mn⁺of the pentacarbonyl manganese bromide coordination center to change from a low self-selected state to a high spin state,which greatly enhances the T₁ imaging effect.