Synthesis And Evaluation Of The Biological Properties Of Sr-CuO Material

Purpose:In this study,based on the bionics principle and synergistic advantages of multiple metal elements,strontium doped copper oxide material（Sr-CuO）with different strontium contents was prepared by hydrothermal method.Based on the characterization of its microstructure,its antibacterial、angiogenesis and osteogenic properties were further characterized in vitro.Hoping to prepare a new inorganic biological material with good antibacterial、angiogenic and osteogenic properties.Methods1.Using hydrothermal method prepared strontium doped copper oxide with different strontium contents（xSr-CuO,x=0,5,10,15at%）,respectively using the X-ray powder diffraction（XRD）technology to analyze its phase,field emission scanning electron microscopy（FESEM）to observe its surface morphology and the coupled ion emission spectrum（ICP）to detect strontium ion(Sr²⁺)doping copper oxide（CuO）on the influence of copper ion(Cu²⁺)dissolution rate;2.Using Gram-positive bacteria（Staphylococcus aureus）and Gram-negative bacteria（Escherichia coli）as experimental strains,the antibacterial properties of xSr-CuO were detected and evaluated by plate counting method;3.CCK8 method was used to detect and evaluate the cytotoxicity of xSr-CuO on HUVECs in vitro.Cell proliferation test was used to detect the material’s influence on HUVECs proliferation,and scratch test was used to detect the material’s influence on HUVECs migration.RT-qPCR was used to detect the material’s influence on the expression level of angiogenesis related genes in HUVECs;4.CCK8 method was used to detect and evaluate the cytotoxicity of xSr-CuO on mouse precranial bone cells（MC3T3-E1）in vitro.Cell proliferation test was used to detect the material’s effect on MC3T3-E1cells proliferation,and RT-qPCR was used to detect the material’s effect on the expression level of osteogenic differentiation related genes in MC3T3-E1 cells.Results1.XRD results showed that Sr²⁺was successfully doped into the lattice of CuO,no impurity phase and new phase are formed,and the doping modification did not change the crystal structure of CuO;Scanning electron microscope observation showed that the synthesized CuO was rod-like.The rod-like structure of CuO did not change after Sr²⁺doping,but the size of CuO increased slightly and there was a certain degree of agglomeration.ICP analysis results showed that Sr²⁺doping could promote the dissolution rate of Cu²⁺in CuO,and 10%Sr-CuO material had the highest concentration of Cu²⁺and the fastest Cu²⁺release rate;2.Antibacterial test results showed that Sr-CuO had better antibacterial performance than pure CuO,and 10%Sr-CuO material had the best antibacterial performance.In addition,pure CuO and Sr-CuO material had better antibacterial effect against Staphylococcus aureus than Escherichia coli.3.Cell proliferation experiments showed that 10%Sr-CuO and 15%Sr-CuO at 200μg/ml could significantly promote the proliferation of HUVECs.Scratch experiments showed that xSr-CuO could significantly promote the migration of HUVECs,and 10%Sr-CuO had the most significant effect on migration.RT-qPCR showed that the expression levels of vascular endothelial growth factor（VEGF）and basic fibroblast growth factor（b FGF）were significantly increased in xSr-CuO group,and the b FGF gene expression level was the highest in the 15%Sr-CuO group;4.Cell proliferation experiment showed that 10%Sr-CuO and 15%Sr-CuO at 200μg/ml could significantly promote the proliferation of MC3T3-E1 cells.RT-qPCR showed that the expression levels of osteocalcin（OCN）and specific transcription factor 2（Run X2）were significantly increased in xSr-CuO group,and the expression levels of OCN and Run X2 genes were the highest in the 10%Sr-CuO group.Conclusion1.Sr²⁺is successfully doped into the lattice of CuO by hydrothermal method.Pure CuO and Sr-CuO material are rod-like structures with high purity and no impurity phase.Sr²⁺doped CuO can significantly promote the dissolution rate of Cu²⁺;2.The antibacterial performance of Sr-CuO is better than that of pure CuO.The antibacterial effect of pure CuO and Sr-CuO material on Staphylococcus aureus is better than that of Escherichia coli;3.Sr-CuO material plays a good role in promoting angiogenesis;4.Sr-CuO material plays a good role in promoting osteogenesis;5 The biological activity of Sr-CuO material is not directly proportional to the Sr²⁺doping content,and there is an optimal Sr²⁺doping content,10%Sr-CuO and 15%Sr-CuO materials show better biological activity.