基于免疫磁捕获与Mie散射理论的微生物快速鉴定系统研究

With the aggravation of environmental pollution and the continuous destruction of ecological balance, the bacteria were becoming more varied, and the pathogenic microorganism was growing a greater threat to humans..There were a number of problems in present existing microorganism identification systems, such as the low veracity and sensitivity, the complex operating steps, the long testing time, the high cost or even numerous staff members to participate in. Therefore, it was imperative to develop an automatic microorganism identification system which could be accurate, time-saving, energy-saving and cost-saving..In the previous studies, we synthesized the immunomagnetic beads (IMB) to enrich the microorganism and also built the experimental platform which was based on Mie scattering theory to test Fe3O4 spheres. Finally, the microbial rapid identification system based on immune magnetic capture and Mie scattering theory was innovatively proposed..The success of pre-experiment indicated that the research idea of this subject which combined nano science, material science with optics organically was feasible. The use of IMB can avoid pure culture, reduce testing time and realize automatic detection easily. The light scattering technique could avoid using biochemical reagent, reduce testing cost. And in addition to ensure the detection accuracy, it will also increase testing speed..Consequently, our research will further improve the design of the hardware and software systems, make experiment confirm in a certain number of microbial samples and finally it will provide new technology for the clinical microorganism identification.

随着环境污染的加剧和生态平衡的不断破坏，导致致病菌的种类越来越多，病原微生物对人类的威胁越来越大。现有的鉴定系统存在诸如准确性低、灵敏性不高，操作步骤复杂、检测时间长、成本高而且要有大量人员参与等问题，因此，研制出一种准确、省时、省力和省成本的自动化微生物快速鉴定系统势在必行。前期研究中，我们合成了免疫磁珠对微生物进行富集，构建了基于Mie散射理论实验平台对Fe3O4微球进行检测，创新性地提出了“基于免疫磁捕获与Mie散射理论的微生物快速鉴定系统”，预实验成功表明本课题将纳米科学、材料科学与光学有机结合的研究思路有可行性。使用免疫磁珠，可以避免纯培养，减少了检测时间，且容易实现自动化检测；使用光散射技术，不需使用生化试剂，降低了检测成本，在确保检测精度的同时提高了检测速度。因此本研究拟进一步优化系统软硬件设计，并在一定数量微生物样本中进行论证，将为临床微生物快速鉴定提供新技术。

微生物鉴定系统目前存在诸如准确性低、灵敏性不高，操作步骤复杂、检测时间长、成本高而且要有大量人员参与等问题，本项目针对上述问题，基于磁性纳米分离富集放大技术和光散射技术，研制了一种新型微生物快速鉴定系统。使用免疫磁珠，可以避免纯培养，减少了检测时间，且容易实现自动化检测；使用光散射技术，不需使用生化试剂，降低了检测成本，在确保检测精度的同时提高了检测速度。.通过免疫磁珠合成与修饰研究，获得了富集效率显著的磁性纳米颗粒，并将该磁性纳米颗粒应用在了微生物、病原体等检测方面；系统采用由5根半圆弧轴组成的球形笼状结构，待检测样本置于球形玻璃器皿中，放置于球形笼状结构的球心处的支架上。半圆弧轴上等间距安装32个光电探测器，收集微生物空间散射光的结构。通过光电探测器收集到的散射光信号，基于MIE散射理论，解算得到微生物的形态特征参数。通过光路优化设计、反演算法研究，实现了对三种临床上常见的微生物：（a）粪肠球菌（b）绿浓杆菌和（c）大肠杆菌的快速鉴定，准确率约为80%。.通过算法的不断优化和系统性能的改进，提高鉴定准确率和重复性，未来能够鉴定更多不同类型的微生物，有望应用于病原体现场快速鉴定等场合。