College of Food Science and Engineering, Northwest A&F University, Yangling 712100, Shaanxi, China.
Department of Chemistry, University of Turin, Via Pietro Giuria 7, 10137 Turin, TO, Italy.
Food Chem. 2023 Oct 30;424:136416. doi: 10.1016/j.foodchem.2023.136416. Epub 2023 May 19.
Rapid separation and identification of Salmonella enteritidis (S. enteritidis) in food is of great importance to prevent outbreaks of foodborne diseases. Herein, by using O and H antigens as targets, an epitope-based bio-panning strategy was applied to isolate specific nanobodies towards S. enteritidis. This method constitutes an efficient way to obtain specific antibody fragments and test pairwise nanobodies. On this basis, a double nanobody-based sandwich enzyme-linked immunosorbent assay (ELISA) coupled with immunomagnetic separation (IMS) was developed to rapid enrich and detect S. enteritidis in food. The detection limit of the IMS-ELISA was 3.2 × 10 CFU/mL. In addition, 1 CFU of S. enteritidis in food samples can be detected after 4-h cultivation, which was shortened by 2 h after IMS. The IMS-ELISA strategy could avoid matrix interference and shorten the enrichment culture time, which has great potential for application in monitoring bacterial contamination in food.
快速分离和鉴定食品中的肠炎沙门氏菌（S. enteritidis）对于预防食源性疾病的爆发非常重要。在此，通过使用 O 和 H 抗原作为目标，应用基于表位的生物淘选策略来分离针对 S. enteritidis 的特异性纳米抗体。该方法构成了获得特异性抗体片段和测试成对纳米抗体的有效途径。在此基础上，建立了一种基于双纳米抗体的夹心酶联免疫吸附测定（ELISA）结合免疫磁分离（IMS），用于快速富集和检测食品中的肠炎沙门氏菌。IMS-ELISA 的检测限为 3.2×10 CFU/mL。此外，在 IMS 后，经过 4 小时培养，食品样品中 1 CFU 的肠炎沙门氏菌即可被检测到，这比未经 IMS 缩短了 2 小时。IMS-ELISA 策略可以避免基质干扰并缩短富集培养时间，在监测食品中的细菌污染方面具有很大的应用潜力。
