Improving the sensitivity of lateral flow immunoassay for Salmonella typhimurium detection via flow-rate regulation

Zhen Du; Yufei Wang; Deyun He; Enbo Xu; Qingqing Chai; Zhengyu Jin; Zhengzong Wu; Bo Cui

doi:10.1016/j.foodchem.2022.133756

Improving the sensitivity of lateral flow immunoassay for Salmonella typhimurium detection via flow-rate regulation

Food Chem. 2022 Dec 15:397:133756. doi: 10.1016/j.foodchem.2022.133756. Epub 2022 Jul 22.

Authors

Zhen Du¹, Yufei Wang¹, Deyun He², Enbo Xu³, Qingqing Chai¹, Zhengyu Jin⁴, Zhengzong Wu⁵, Bo Cui⁶

Affiliations

¹ State Key Laboratory of Biobased Material and Green Papermaking, School of Food Science and Engineering, Qilu University of Technology, Shandong Academy of Sciences, Jinan 250353, China.
² School of Bioengineering, Qilu University of Technology, Shandong Academy of Sciences, Jinan 250353, China.
³ College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, China.
⁴ State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China.
⁵ State Key Laboratory of Biobased Material and Green Papermaking, School of Food Science and Engineering, Qilu University of Technology, Shandong Academy of Sciences, Jinan 250353, China. Electronic address: wzzqlu@hotmail.com.
⁶ State Key Laboratory of Biobased Material and Green Papermaking, School of Food Science and Engineering, Qilu University of Technology, Shandong Academy of Sciences, Jinan 250353, China. Electronic address: cuib@qlu.edu.cn.

PMID: 35901614
DOI: 10.1016/j.foodchem.2022.133756

Abstract

Application of the traditional immunochromatographic assay (ICGA) has been limited by its poor sensitivity. The objective of this study was to increase the sensitivity of the traditional ICGA. A dual-mode ICGA (D-M ICGA) was developed by combining a nanozyme-assisted signal-amplification strategy with a magnetic-nanoparticle-based flow-speed-control strategy. Salmonella typhimurium can be detected simultaneously based on color and magnetic signals in the detection area of the D-M ICGA strip. The calculated limits of detection of 50 cfu·mL^-1 and 75 cfu·mL^-1 in the color and magnetic modes, respectively, were approximately 1000 times lower than those of the traditional ICGA. The selectivity and practical applicability of the D-M ICGA were also confirmed in this study. The results prove that the D-M ICGA is an assay that could be used for Salmonella typhimurium detection and can be easily adapted to detect other pathogenic bacteria.

Keywords: Bacteria; Flow-speed control; Immunochromatographic assay; Nanozyme; Signal amplification.

MeSH terms

Immunoassay / methods
Salmonella typhimurium*