中文摘要：

采用聚苯乙烯磺酸钠（PSS）作为调控剂,将其加入到氯化钙和碳酸钠溶液反应体系中成功制备出表面粗糙的碳酸钙微球（粒径平均约为510nm）,采用场发射扫描电镜（FE-SEM）、红外光谱（FTIR）、X-射线衍射（XRD）和动态光散射（DLS）等对碳酸钙微球颗粒进行表征。MTT实验显示碳酸钙微球毒性具有浓度依赖性,在终浓度〈1mg/mL时,细胞存活率都可达60%以上,显示出很低的细胞毒性,具有良好的生物相容性。不同pH值条件下碳酸钙微球的降解实验结果显示碳酸钙微球在酸性pH下能够更快速地降解,说明碳酸钙微球能够响应酸性pH值,具有pH依赖性。将碳酸钙微球经PEI表面修饰后用于负载质粒DNA,通过琼脂糖凝胶电泳及体外转染实验结果证实碳酸钙微球能够有效负载质粒DNA,并可在癌细胞内成功表达发出绿色荧光。这些研究结果显示将碳酸钙微球作为一种安全的非病毒基因载体用于基因治疗领域具有潜在的应用价值。

英文摘要：

This study uses sodium polystyrene sulfonate（PSS）as regulating agent,adds it to the reaction system of calcium chloride and sodium carbonate solution,successfully prepares calcium carbonate microparticles with rough surface（average particle size is about 510nm）and uses field emission scanning electron microscope（FE-SEM）,infrared spectroscopy（FTIR）,X-ray diffraction（XRD）and dynamic light scattering（DLS）to characterize calcium carbonate microparticles.MTT experiment shows that the toxicity of calcium carbonate microparticles has concentration dependency.When final concentration〈1mg/mL,cell survival rate can be more than 60%.It shows a very low cytotoxicity and good biocompatibility.The result of degradation experiment of calcium carbonate microparticles under different conditions of pH value shows that calcium carbonate microparticles can degrade more rapidly under acid pH,indicating that calcium carbonate microparticles can respond to acid pH value and have pH dependency.Calcium carbonate microparticles are used to load plasmid DNA after PEI surface modification.The result of agarose gel electrophoresis and transfection in vitro proves that calcium carbonate microparticles can load plasmid DNA effectively and express and emit green fluorescence successfully in cancer cell.These research results show that the use of calcium carbonate microparticles in the field of gene therapy as a safe non-viral gene carrier has potential application value.