【摘要】 报道了一种新型的免疫荧光检测技术,基于免疫磁珠富集,免疫量子点标记,建立了一种快速检测食品中沙门氏菌含量的方法。采用反相微乳液法,通过二氧化硅包裹磁性γ-Fe2O3微粒,得到高分散性,粒径均匀的核壳型磁性纳米粒子。通过修饰氨基硅烷使纳米粒子具有生物相容性,并可与抗体交联反应。在富集过程中免疫磁珠能与目标致病菌形成"磁珠-细菌"复合物。基于抗原抗体的特异性反应,免疫量子点被标记到目标致病菌上,形成(磁珠-细菌-量子点)"三明治"式复合物。通过荧光显微镜来观察量子点的荧光来测试体系中致病菌的污染情况。检测结果表明,磁珠富集、功能免疫量子点标记法检测沙门氏菌的检出限为105cfu/mL,检测时间为2h。更多还原

【Abstract】 This paper reported a new rapid detection method of Salmonella via a combined approach of magnetic microparticles for enrichment and antibody-conjugated semiconductor quantum dots(QDs) as fluorescence markers.With the water-in-oil reverse microemulsions method,the γ-Fe2O3 magnetic nanoparticles were coated with silica to empower the particles with high dispersion and compatibility to biomacromolecule.The magnetic beads were designed by modifying with the amino silane,which could immobilize antibody by cross linking reaction.The immune magnetic beads and pathogenic bacteria formed "bead-cell"complexes in the enrichment procedure.And the antibody-conjugated QDs would be marked on the "bead-cell"complexes to form the"sandwich"complexes based on antigen-antibody reaction.Fluorescence microscope were be used to examine the fluorescence of sample to determine it’s microorganism polluting condition.The examination results indicated that the minimum level of this method is 105 cfu/mL,and detection time is about 2 hours.更多还原