摘要
以CdCl2和Na2S为原料,以巯基乙酸为稳定剂,采取水相合成方法制备了CdS量子点。结果表明,合成CdS量子点最佳条件是:作用时间3h,[Cd2+]∶[S2-]为2∶1,50μL稳定剂,pH8.0,反应温度30℃。通过EDC.HCl和NHS的作用,成功地将单增李斯特菌抗体IgG与CdS量子点偶联。偶联后的IgG-CdS荧光强度显著增强,为偶联前的4倍。血清凝集反应和直接免疫荧光实验证明,偶联CdS量子点的单增李斯特菌抗体的特性没有发生变化,在荧光显微镜下可快速灵敏地检测出单增李斯特菌。本方法特异性强、稳定性和重复性高,可用于食品中致病菌的快速检测。
The CdS quantum dots were synthesized by using the precursors including CdCl2 and Na2S and thioglycoli acid （TGA） as stabilizing agent in aqueous solution. The optimal conditions for synthesis of CdS quantum dots were as follows： reaction time of 3 h, 2∶1 of ratio of [Cd2＋] to [S2-], TGA volume of 50 μL, system pH value of 8.0 and reaction temperature of 30 ℃ for preparing the CdS quantum dots. The Listeria monocytogenes antibody IgG was successfully coupled to the CdS quantum dots by using the EDC·HCl and the NHS as coupling reagents. The fluorescence intensity of Listeria monocytogenes antibody IgG coupled with the CdS quantum dots was enhanced significantly and was four times of that coupled before. The results of serum agglutination reaction and direct immunofluorescence test showed that the characteristics of Listeria monocytogenes antibody coupled with CdS quantum dots did not changed, and the Listeria monocytogenes could be detected quickly and sensitively by fluorescence microscope. This method can be effectively used in the rapid detection of pathogens in the food because of its high specificity, stability and repeatability.
出处
《分析化学》
SCIE
EI
CAS
CSCD
北大核心
2010年第5期632-637,共6页
Chinese Journal of Analytical Chemistry
关键词
量子点
单增李斯特菌
偶联
荧光强度
Quantum dots
Listeria monocytogenes
Coupling
Fluorescence intensity
