Development of a rapid, one-step-visual method to detect Salmonella based on IC-LAMP method

• Published in: Iranian journal of veterinary research Vol. 21; no. 1; pp. 20 - 25
• Main Authors: Zhang, L, Du, X, Chen, C, Han, Q, Chen, Q, Zhang, M, Xia, X, Song, Y, Zhang, J
• Format: Journal Article
• Language: English
• Published: Iran School of Veterinary Medicine, University of Shiraz 01.01.2020
• Subjects: Original; Salmonella; LAMP; Monoclonal antibody; Detection; Magnetic Immunocapture
• ISSN: 1728-1997; 2252-0589

can cause serious human gastroenteritis and is frequently isolated from various food samples. The cell culturing, immunoassay, and polymerase chain reactions (PCR) are the current methods to detect such pathogenic agents. However, these methods are time-consuming and labor-intensive, and thus unavailable for rapid-monitoring of . This study aimed to develop an immunocapture-loop-mediated isothermal amplification (IC-LAMP) for rapid and sensitive detection of . was used as antigen to produce monoclonal antibody (mAb) and mAbs were prepared via subcloning three times. The mAb 1B12 with high affinity was coated on the surface of the immuno-magnetic beads (IMBs) to capture . The enriched products (IMBs- ) were used for LAMP using the special primers targeted the conserved gene of . The IC-LAMP was developed based on mAb 1B12 and LAMP. Targeting the conserved gene of , the detection time was shortened to 50 min from three days. If the reaction contains , the green fluorescence and the trapezoidal strip can be clearly observed. Importantly, the method combines the specificity of antibody and LAMP with a detection limit of 5 CFU/ml in artificially contaminated water and milk. The specificity of this method was demonstrated by testing other similar bacteria. The results indicate that the IC-LAMP reacts only with and does not cross-react with other similar bacteria. The IC-LAMP assay developed here is a rapid, sensitive, one-step-visual method to screen for the presence of in food samples. This method is faster than traditional PCR, LAMP, and other methods, and can be used as a primary screening method for the detection.