Subtractive Inhibition Assay Based on PagN‐Specific Monoclonal Antibody for the Detection of Salmonella Using Surface Plasmon Resonance

• Published in: Biotechnology journal 2025-01, Vol.20 (1), p.e202400616-n/a
• Main Authors: Hu, Maozhi, Zhu, Hongji, Meng, Chuang, Ding, Ruiqing, Yan, Qiuxiang, Zhao, Hongyan, Kang, Xilong, Gu, Dan, Pan, Zhiming, Jiao, Xinan
• Format: Article
• Language: English
• Subjects: Animals; Antibodies, Monoclonal - immunology; Bacterial Proteins - immunology; Mice; Milk - microbiology; PagN; salmonella; Salmonella - immunology; Salmonella - isolation & purification; specificity; subtractive inhibition; surface plasmon resonance; Surface Plasmon Resonance - methods
• ISSN: 1860-6768; 1860-7314; 1860-7314
• DOI: 10.1002/biot.202400616

Salmonella is a common foodborne zoonotic pathogen that poses a great threat to human health and breeding industry. The rapid detection of Salmonella is necessary for early prevention and control. In this study, a subtractive inhibition assay (SIA) based on surface plasmon resonance (SPR) for the rapid detection of Salmonella was developed. Mouse‐specific monoclonal antibody 3B3 against Salmonella membrane protein PagN was first incubated with Salmonella. The unbound free antibody was separated using a sequential process of centrifugation and then detected using an immobilized goat anti‐mouse immunoglobulin G polyclonal antibody on the SPR sensor chip. This SIA‐SPR method showed excellent sensitivity for Salmonella with a limit of detection of about 300 CFU mL−1. This method is sensitive to different serotypes of Salmonella strains but not for non‐Salmonella strains. It was able to detect Salmonella in the contaminated water and milk powder at less than 102 and 103 CFU mL−1, respectively, which was consistent with the bacterial plate count results. In addition, this method could be used to evaluate the lysis effect of phages on bacteria. Since the culturing detection method needs more than 48 h, this method has the potential for the rapid and sensitive clinical detection of Salmonella. For our knowledge, this is the first report for Salmonella detection using SIA‐SPR method. Graphical and Lay Summary Rapid quantitative detection of Salmonella is necessary for early prevention and control. However, conventional culture methods need to be more laborious and time‐consuming and is relatively limited in their ability to detect Salmonella in the viable but non‐culturable status. In this study, we developed a subtractive inhibition assay based on surface plasmon resonance for rapid detecting of Salmonella using monoclonal antibody 3B3 against Salmonella membrane protein PagN.