College of Food Science and Engineering, Northwest A&F University, Yangling 712100, Shaanxi, PR China.
College of Food Science and Engineering, Northwest A&F University, Yangling 712100, Shaanxi, PR China.
Food Chem. 2021 May 1;343:128518. doi: 10.1016/j.foodchem.2020.128518. Epub 2020 Oct 31.
Here we present an innovative label-free immunochromatographic strip (ICTS) sensor, in which salt-induced aggregated gold nanoparticles (SIA-AuNPs) act as the signal probe, allowing in 14 min the identification and sensitive quantification of Salmonella as model targets. It has been evidenced that SIA-AuNPs could be absorbed on the surface of bacteria based on van der Waals forces. The SIA-AuNPs@Salmonella complex was captured by anti-Salmonella polyclonal antibody deposited on the test zone. With the label-free ICTS sensor, we successfully detected Salmonella in a concentration range of 10-10 CFU/mL and a visual detection limit of 1 × 10 CFU/mL. The band of test zone could be distinguished at a concentration of 10 CFU/mL by naked eye, which is 100-fold lower than the cationic AuNPs based method. The strip sensor was further validated with real samples including cabbage and drinking water with excellent precision and showed to provide excellent recovery.
在这里，我们提出了一种创新的无标记免疫层析条（ICTS）传感器，其中盐诱导聚集的金纳米粒子（SIA-AuNPs）用作信号探针，可在 14 分钟内识别和灵敏定量沙门氏菌作为模型靶标。已经证明，SIA-AuNPs 可以基于范德华力被吸附在细菌表面。SIA-AuNPs@Salmonella 复合物被固定在测试区的抗沙门氏菌多克隆抗体捕获。使用无标记 ICTS 传感器，我们成功地在 10-10 CFU/mL 的浓度范围内检测到沙门氏菌，并且具有 1×10 CFU/mL 的目视检测限。在 10 CFU/mL 的浓度下，通过肉眼可以区分测试区的条带，比基于阳离子 AuNPs 的方法低 100 倍。该条传感器还进一步用包括白菜和饮用水在内的实际样本进行了验证，具有出色的精度，并显示出良好的回收率。
