Food Safety Laboratory, College of Food Science and Engineering, Ocean University of China, No. 5, Yushan Road, Qingdao, Shandong Province, 266003, PR China.
Food Safety Laboratory, College of Food Science and Engineering, Ocean University of China, No. 5, Yushan Road, Qingdao, Shandong Province, 266003, PR China.
Talanta. 2022 Oct 1;248:123627. doi: 10.1016/j.talanta.2022.123627. Epub 2022 May 30.
There is an urgent need to develop fast and sensitive detection methods for foodborne pathogens. But the conventional culture method that typically requires 2-3 days is not ideal for the rapid analysis. Food samples demonstrate a great challenge for direct detection due to the complex matrix. Hence, we present a new method based on the phage long-tail-fiber proteins (LTF4-a) immobilized magnetic nanoparticles (MNPs) for specific separation and concentration of Salmonella. The LTF4-a-MNP was prepared via the coupling of recombinant LTF4-a with MNPs and used to isolate and enrich Salmonella cells from contaminated food samples. The captured material was further integrated with the direct PCR program for accurate detection of Salmonella. Our study successfully established a new method for detecting contaminated food samples of Salmonella, the overall approach took no more than 3 h, which allowed a detection limit of 7 CFU/mL, demonstrating a promising alternative to the immunomagnetic separation method by replacing antibodies or aptamers, that is compatible with downstream analysis.
目前迫切需要开发用于检测食源性致病菌的快速、灵敏的方法。但是，传统的培养方法通常需要 2-3 天，并不适合快速分析。由于食品样本的基质复杂，直接检测具有很大的挑战性。因此，我们提出了一种基于噬菌体长尾纤维蛋白（LTF4-a）固定化磁性纳米粒子（MNPs）的新方法，用于特异性分离和浓缩沙门氏菌。通过将重组 LTF4-a 与 MNPs 偶联制备 LTF4-a-MNP，用于从污染的食品样本中分离和富集沙门氏菌细胞。捕获的材料进一步与直接 PCR 程序集成，用于准确检测沙门氏菌。我们的研究成功建立了一种用于检测污染食品样本中沙门氏菌的新方法，整个方法耗时不超过 3 小时，检测限为 7 CFU/mL，与免疫磁分离方法相比具有很大的优势，该方法可以替代抗体或适体，与下游分析兼容。
