利用磁性纳米金对鼠伤寒沙门氏菌的SERS检测研究
首发时间:2015-03-12
摘要:目的:本文研究了一种利用信号分子、适配体修饰的纳米金与适配体修饰的磁性纳米金夹心结构检测鼠伤寒沙门氏菌的新方法。方法:小颗粒纳米金与信号分子巯基苯甲酸(4-MBA)通过Au-S键结合,再与适配体孵育结合,作为拉曼信号探针。磁性纳米金与适配体孵育,作为捕获探针。捕获探针首先与细菌37 ℃下孵育70 min,清洗三次,加入信号探针相同条件孵育,清洗重分散,进行拉曼检测。结果:在最优条件下检测,鼠伤寒沙门氏菌浓度在10 cfu/mL~107 cfu/mL范围内,拉曼光谱强度与平板计数法得到的菌落个数的对数值具有良好的线性关系(R2=0.9926),检测限为5 cfu/mL。结论:信号探针与捕获探针通过靶标结合,金表面等离子共振效应增强,从而对拉曼信号产生进一步的扩大。适配体的捕获效率较抗体-抗原有更强的结合力,结果更可靠。将磁珠更换为磁性纳米金,不仅能使体系分散更均匀,还能增强拉曼效应。此方法具有简单,快速,灵敏度高,特异性好的特点,可用于实际样品的检测。
关键词: 食品的微生物检验 磁性纳米金-适配体 适配体&信号分子-纳米金 鼠伤寒沙门氏菌 夹心结构
For information in English, please click here
Detection of Salmonella typhimurium by SERS-based Sandwich Structure Using Aptamer-Functionalized Magnetic Gold Nanoparticles
Abstract:Purpose:The assay studied a method of the detection for Salmonella Typhimurium by SERS-based sandwich structure using aptamer-functionalized magnetic gold nanoparticals (MGNPs) and aptamer&signal molecular-functionalized gold nanoparticals (GNPs). Method:Raman signal probe: Mercaptobenzoic acid (4-MBA) are linked to the small gold nanoparticles through Au-S Bond, then, aptamers are added and incubate at 37 ℃ for 24 h. Capture probe are prepared through direct linkage between magnetic gold nanoparticles(GNPs) and aptamers during incubation. Capture probe and Salmonella Typhimurium were incubated at 37 ℃ for 70 min, washed three times with PBS, raman signal probe were then added and incubated at the same condition, wash three times with PBS for the further test. The result: Under optimal detection condition, in the range of 10 cfu/mL~107 cfu/mL, Raman Intensity and the number of colonies got from plate count method have a good linear relationship (R2=0.9926), the LOD is 5 cfu/mL. Conclusion: Raman signal probe and capture probe are connected through Salmonella Typhimurium, enhancing gold surface plasmon resonance effect, and thus the Raman signal get a further expansion. Aptamers' capture efficiency is higher compared to antibody-Antigen. Aptamer's capture efficiency was higher compared to antibody-Antigen, guaranteed the good specificity. Fe3O4/Au core-shell nanoparticles (MGNPs) has a better dispersibility, which can enhance the Raman scattering effect, and help get more accurate results. This method is simple, rapid, and of high sensitivity and specificity, can be used to detect actual samples
Keywords: Food Microorganism Testing Aptamer-Functionalized Gold Magnetic Nanoparticles Aptamer&Signal Molecular-Functionalized Gold Nanoparticals Salmonella Typhimurium Sandwich
论文图表:
引用
No.4633059953971142****
同行评议
共计0人参与
勘误表
利用磁性纳米金对鼠伤寒沙门氏菌的SERS检测研究
评论
全部评论0/1000