基于SiO2荧光纳米粒子快速检测果汁中 大肠杆菌的免疫传感器研究

Biosensor for rapid detection of Escherichia coli in juice by luminophore-doped silica

中文关键词:  SiO2荧光纳米粒子  大肠杆菌O157:H7  快速检测  生物传感器  果汁

英文关键词:luminophore-doped silica  Escherichia coli O157:H7  rapid detection  biosensor  juice

中文摘要:

      目的 设计一种基于SiO2荧光纳米粒子快速检测果汁中大肠杆菌O157:H7的新型传感器。方法 采用超分子组合法将荧光基团嵌入到SiO2纳米颗粒中合成SiO2荧光纳米粒子, 然后将抗大肠杆菌O157:H7的单抗偶联到纳米粒子表面, 最后通过抗原-抗体反应使纳米粒子与待检细菌结合, 使用荧光显微镜观察并统计大肠杆菌O157:H7的个数。结果 本方法与革兰氏染色法相比, 对大肠杆菌O157:H7计数结果无统计学差异(P=0.930); 该方法整个检测过程能够在15 min内完成, 检测下限小于10 CFU/mL。结论 该方法能增强检测果汁中大肠杆菌O157:H7的灵敏度, 缩短检测时间, 对其他病原体检测方法的改进具有重要的指导意义。

英文摘要:

      Objective To design a new biosensor for rapid detection of Escherichia coli O157:H7 in juice by synthesized luminophore-doped silica (LDS) nanoparticles. Methods The fluorescent groups were embed into SiO2 nanoparticles to synthesize LDS by supramolecular combination method. Then E. coli O157:H7 specific monoclonal antibody was coupled to the surface of the dye doped nanoparticles. Finally, antibody-coated narnoparticles incorporated with the cells of O157:H7 by antigen-antibody reaction to form conglutinations, which represented the images of the detected germs and could be observed and counted by fluorescence microscope. Results The number of E. coli O157:H7 was detected and counted with methods of fluorescent nanoparticles staining and gram staining, which had no significant difference (P=0.930). The novel developed LDS nanoparticles could finish the detection within 15 mins, and had the limit of detection of 10 CFU/mL. Conclusion The method of LDS nanoparticles can enhance the sentivity of O157:H7 detection and obviously shorten testing time, which has important significance for the improvement of inspection methods for other pathogenic microorganisms.