血液毒素分子印迹羟基磷灰石纳米膜靶向识别及光自洁行为研究

In the present draft, a novel inorganic nanometer film would be developed for purification of blood toxins, based on the modification of molecularly imprinted hydroxyapatite nanometer film onto high-frequency gold-plated quartz crystal by molecular imprinting and surface sol-gel techniques, and the proper parameters would be established and used to characterize the interface of imprinted film. The kinetics of adsorption and photocatalytic degradation of the blood toxins (etc. bilirubin, creatinine, uric acid, middle molecules) on molecularly imprinted hydroxyapatite nanometer film would be in situ studied by the high-frequency quartz crystal microbalance with extreme sensitivity to mass change, and the factors affecting the adsorption and degradation of blood toxins would be also investigated in detail. The interaction between molecularly imprinted hydroxyapatite nanometer film and blood toxins would be further investigated using atomic force microscopy and spectroscopic techniques, and the interaction mechanism would be evaluated by the quantum chemistry, surface chemistry and photocatalytic theories. The purpose of the work would like to understand the unknown interaction laws between molecularly imprinted hydroxyapatite nanometer film and blood toxins, and provide theoretical guidance for the application of molecularly imprinted hydroxyapatite nanometer film to hemoperfusion treatment.

本项目拟采用表面溶胶凝胶法、分子印迹技术在高频镀金石英晶片表面构筑净化血液毒素的分子印迹羟基磷灰石纳米膜，建立适当参数描述印迹界面特征；基于高频石英晶体微天平的高灵敏质量传感现场研究血液毒素（如：胆红素、肌酐、尿酸、中分子物质等）在分子印迹羟基磷灰石纳米膜上吸附、光催化降解等过程动力学行为，探讨影响血液毒素吸附及降解的因素；采用原子力显微镜、光谱学技术等进一步研究分子印迹羟基磷灰石纳米膜上血液毒素的作用行为，结合量子化学理论﹑表面化学理论及光催化理论探讨其机制，获得血液毒素在分子印迹无机纳米膜上作用规律的新认知，为分子印迹羟基磷灰石纳米膜应用于血液灌流治疗提供理论指导。

本课题采用表面溶胶凝胶和分子印迹技术制备了基于分子印迹羟基磷灰石（MIH）的Fe3O4/SiO2/MIH、Fe3O4/羟基磷灰石(HAP)/分子印迹聚吡咯(MIPPy)膜修饰磁性玻碳电极（MGCE）及MIH膜修饰石英晶体，优化了MIH的制备方法，着重探讨了血液毒素在MIH上的作用过程和机理以及MIH对血液毒素的选择性和可再生循环使用性。研究结果表明：Fe3O4/SiO2/MIH和Fe3O4/HAP/MIPPy纳米粒近似球形、单分散、尺寸分布均匀，具有较强磁化强度和超顺磁性；SEM和电化学测试表明在MGCE和石英晶体上形成了MIH膜；MIH对血液毒素浓度响应范围宽，呈现出高选择性、灵敏度和光催化活性；MIH膜上吸附血液毒素的光催化降解符合准一级动力学过程，其降解速率常数为8.05×10-4 s-1，是非印迹HAP膜上的2倍；MIH膜上增强的光催化降解可归因于印迹膜对血液毒素的靶向识别性，结果更多的血液毒素分子集聚于电极表面并被光降解，导致了较高的频率响应、光电流及光降解率；血液毒素的光降解机理为UV光照下MIH发生光致电子激发，生成具有强氧化性的•O2-和•OH自由基，氧化降解了MIH上吸附的血液毒素；MIH在连续重复使用及长期存放过程中，响应信号仅出现了轻微下降，表明制备的血液毒素MIH具有良好的可再生循环使用性。在本课题的资助下，共发表SCI收录论文11篇，出版专著1部，授权发明专利1项。