【作者】 陈敏； 严钟煜； 潘磊庆； 屠康；

【Author】 Chen Min;Yan Zhongyu;Pan Leiqing;Tu Kang;College of Food Science and Technology,Nanjing Agricultural University;

【机构】 南京农业大学食品科技学院；

【摘要】 志贺氏菌是一种革兰氏阴性菌,进入人体易造成感染性疾病痢疾的产生,故又称痢疾杆菌,但目前对于志贺氏菌的检测仍受到选择性及灵敏度低的限制。因此,为实现对志贺氏菌快速高效的检测,本文将探究构建一种基于上转换与金纳米之间荧光共振能量转移效应的应用于志贺氏菌上的新型荧光检测方法。在本研究中,互补链修饰的上转换纳米颗粒(UCNPs)可以在980 nm激光激发下在500～700 nm处提供稳定的黄绿色荧光。同时,通过"Au-S"键相互连接形成的志贺氏菌适配体修饰的金纳米颗粒(GNPs)作为荧光共振能量转移(FRET)的受体和识别元件,可以特异性结合志贺氏菌,并显著淬灭互补链修饰的UCNPs的荧光。结果表明,我们构建的纳米探针,其荧光在1.2×10~2至1.2×10~8CFU/mL的范围内随着志贺氏菌的增加而增加,呈线性关系(Y=191.6X+2 299),检测限低至30CFU/mL。此外,所制备的上转换荧光纳米探针可以在1 h内实现污染鸡中志贺氏菌的检测,而无需富集。此方法灵敏度高且选择性强,可以满足我们日常快速检测志贺氏菌的需要。更多还原

【Abstract】 Shigella,as a typical foodborne pathogen has strong survivability in the environment or food,leading to infectious diseases,yet its rapid detection technology with high selectivity and sensitivity remains challenging.In this study,complementary strand modified upconversion nanoparticles(UCNPs) can offer stable yellow-green fluorescence at 500-700 nm excited by a 980 nm laser.Importantly,Shigella aptamerl modified gold nanoparticles(GNPs) formed by "Au-S" bond act as a fluorescence resonance energy transfer(FRET) donor and recognition element that can bind specifically to Shigella and significantly quench the fluorescence of complementary strand modified UCNPs.As a result,the fluorescence of our developed nanoprobe increased linearly with the increase in Shigella in a wide range from 1.2 × 10~2 to 12 × 10~8 CFU/mL and the detection limit was as low as 30 CFU/mL.Moreover,the fabricated upconversion fluorescence nanoprobe can achieve Shigella detection in contaminated chicken without enrichment in 1 h.更多还原