Synthesis,characterization And Properties Of Three Nitrogen Macrocyclic Compounds Containing Phosphonic Acid Loaded On TiO₂

Superoxide anion(O₂^-.)and hydrogen peroxide（H₂O₂）as the main toxic oxygen species can cause a series of problems such as food spoilage and human aging.Superoxide dismutase（SOD）as a natural scavenger can convert superoxide anion into oxygen and hydrogen peroxide.Therefore,these can be widely used in food,medicine,daily chemical and other fields.But in fact the application has been limited because the high cost of purifying and changes about the environment（such as temperature,pH,etc.）can affect natural enzymes.In order to solve these defects of natural SOD,a large number of metal complexes have been synthesized with SOD activity.On the other hand,some solid materials have been used as the carrier like titanium dioxideto improve the stability and repeatability of mimic enzyme.And also study on Photocatalytic Degradation of Dye.At present,metal organic framework complexes and TiO₂ catalyst materials has a good application in adsorption,catalysis.The research object of this paper is metal complexes containing phosphonic acid,which is based on the predecessors’works,and the structure and function of macrocyclic polyamine compounds.The products were characterized by IR,TGA,XRD and SEM.Superoxide dismutase activity is determined by NBT method and the degradation of dye is mainly determined by Fenton-Like Oxidation.The main results are as follows:（1）In order to simulate the structure of natural Mn-SOD,Mn₃{C₉N₃H₁₈（PO₃）₃}（H₂O）₆·1.5H₂O complex was synthesized by notph6（1,4,7-triazacyclononane-1,4,7-triyl-tris（methylene-phosphoic acid））,and the complex was loaded on the solid surface of titanium dioxide to prepare the catalyst.The activity of SOD was measured:IC₅₀=0.04 mg/mL.（2）Based on the complex structure of Mn₃{C₉N₃H₁₈（PO₃）₃}（H₂O）₆·1.5H₂O,the ligand and copper salt were reacted at a molar ratio of 1:3 to obtain Cu complex,and the structure of the complex was verified by a series of characterization.The complex was loaded with the titania material and the SOD activity unit was measured:IC₅₀=0.016 mg/mL.（3）The catalyst of Mn₃{C₉N₃H₁₈（PO₃）₃}（H₂O）₆·1.5H₂O was loaded on titania solid was placed in hydrogen peroxide to degrade rhodamine B dye.In the reaction system,the effects of the dosage,initial value,hydrogen peroxide dosage,reaction temperature and initial concentration of the catalyst were discussed.The optimum reaction conditions of discolor rhodamine B was determined.