Bu Tong, Jia Pei, Liu Jinghan, Liu Yingnan, Sun Xinyu, Zhang Meng, Tian Yongming, Zhang Daohong, Wang Jianlong, Wang Li
College of Food Science and Engineering, Northwest A&F University, Yangling 712100, Shaanxi, China.
Food Chem X. 2019 Aug 23;3:100052. doi: 10.1016/j.fochx.2019.100052. eCollection 2019 Sep 30.
Gold nanoparticles (AuNPs)-based lateral flow strip (LFS) enables a quick screening of foodborne bacteria in point-of-care (POC) diagnostics but suffers from the cumbersome labeling of antibodies and poor sensitive performance. Here, we innovated a label-free immunoassay to detect pathogenic bacteria by introducing diversely positive charges functionalized AuNPs ((+) AuNPs). The (+) AuNPs can be loaded on negatively charged bacteria via electrostatic interaction, leading to a color labeling to target bacteria. Afterward, the (+) AuNPs-bacteria complex can be specifically captured by monoclonal antibody (McAb) immobilized on test (T)-line. Under optimum conditions, the proposed LFS exhibited a lowest detectable concentration of 10 CFU/mL for () and could be well applied in drinking water, lettuce and pork samples. Moreover, this novel (+) AuNPs-LFS possessed a universal applicability, which could also be used for detecting O157 ( O157) with a superior sensitivity (10 CFU/mL) and specificity.
基于金纳米颗粒（AuNPs）的侧向流动试纸条（LFS）能够在即时检测（POC）诊断中快速筛查食源细菌，但存在抗体标记繁琐和灵敏性能不佳的问题。在此，我们通过引入不同正电荷功能化的AuNPs（(+) AuNPs）创新了一种无标记免疫分析法来检测病原菌。(+) AuNPs可通过静电相互作用负载在带负电荷的细菌上，从而对目标细菌进行颜色标记。之后，(+) AuNPs-细菌复合物可被固定在检测（T）线上的单克隆抗体（McAb）特异性捕获。在最佳条件下，所提出的LFS对()的最低可检测浓度为10 CFU/mL，并且可很好地应用于饮用水、生菜和猪肉样品中。此外，这种新型的(+) AuNPs-LFS具有普遍适用性，还可用于检测O157（O157），具有优异的灵敏度（10 CFU/mL）和特异性。
