将免疫荧光纳米标记技术与激光共聚焦显微成像方法相结合,发展了一种基于二氧化硅荧光纳米颗粒和核酸染料SYBR Green Ⅰ的双色显微成像技术用于大肠杆菌O157∶H7的检测.采用联吡啶钌(RuBpy)二氧化硅荧光纳米颗粒对羊抗大肠杆菌O157∶H7...将免疫荧光纳米标记技术与激光共聚焦显微成像方法相结合,发展了一种基于二氧化硅荧光纳米颗粒和核酸染料SYBR Green Ⅰ的双色显微成像技术用于大肠杆菌O157∶H7的检测.采用联吡啶钌(RuBpy)二氧化硅荧光纳米颗粒对羊抗大肠杆菌O157∶H7抗体进行修饰,基于抗体-抗原相互作用实现了其对目标大肠杆菌O157∶H7的特异性标记;同时以核酸染料SYBR GreenⅠ对细菌进行染色,将细菌和纳米颗粒团聚体区分开,实现了对大肠杆菌O157∶H7的双色标记,并通过激光共聚焦显微镜进行免分离的荧光成像检测.结果表明,该方法可用于缓冲溶液体系和混合细菌样品中目标大肠杆菌O157∶H7的特异性检测,在仅含5%目标菌的混合样品中仍能观察到具有明显黄色荧光的大肠杆菌O157∶H7,且整个检测步骤包括样品预处理可在3 h内完成.该方法则具有较好的灵敏度,可检出2.6×103 Cell/mL的目标细菌样品.若采用针对其它病原菌细胞壁抗原的特异性抗体,则有望发展成为一种通用技术用于多种病原菌的快速和灵敏检测.展开更多
A novel method was developed to fabricate monodispersed nanocomposite SiO2 sphere (200￣400 nm) containing homogeneously dispersed Ag nanoparticles (2￣6 nm). The morphology of inclusion was controlled through the N-[...A novel method was developed to fabricate monodispersed nanocomposite SiO2 sphere (200￣400 nm) containing homogeneously dispersed Ag nanoparticles (2￣6 nm). The morphology of inclusion was controlled through the N-[3-(Trimethoxysilyl)Propyl]ethylene diamine. TEM images showed that the silver nanoparticles were doped uniformly in silica spheres. UV-Vis showed that the doped silver nanoparticles have a plasmon resonance absorption band at 433 nm. Also SEM, EDX, XRD analyses were conducted to characterize thus-prepared sam- ples.展开更多
文摘A novel method was developed to fabricate monodispersed nanocomposite SiO2 sphere (200￣400 nm) containing homogeneously dispersed Ag nanoparticles (2￣6 nm). The morphology of inclusion was controlled through the N-[3-(Trimethoxysilyl)Propyl]ethylene diamine. TEM images showed that the silver nanoparticles were doped uniformly in silica spheres. UV-Vis showed that the doped silver nanoparticles have a plasmon resonance absorption band at 433 nm. Also SEM, EDX, XRD analyses were conducted to characterize thus-prepared sam- ples.
