Highly sensitive smartphone-based detection of Listeria monocytogenes using SYTO9

Listeriosis is caused by Listeria monocytogenes (LM) and is currently considered to be one of the leading food-borne diseases worldwide, with mortality rate of 20%similar to 30%. Currently, detection methods for LM are time-consuming with low sensitivity, and delayed detection results. SYTO9 has a high affinity for DNA and exhibits enhanced fluorescence upon binding. Therefore, this study used SYTO9 staining and image processing to develop a rapid loop mediated isothermal amplification (LAMP) detection method for LM. Smartphone was successfully used for detecting the color change in different concentrations of LM. Besides, the optimized LAMP reaction temperature was 63 degrees C by color identification, and the limit of detection for LM was 6 copies/mu L in the green channel. So, the developed method, based on image processing, is simple, sensitive and rapid, which provides a new idea and method for rapid detection of LM and other food-borne bacterial pathogens. (C) 2021 Published by Elsevier B.V. on behalf of Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences.

Automated summary

Listeriosis, caused by Listeria monocytogenes (LM), is a major global foodborne disease with a high mortality rate of 20% to 30%. Current LM detection methods are time-consuming and have low sensitivity. This study developed a rapid detection method using SYTO9 staining and image processing, based on loop-mediated isothermal amplification (LAMP). The method was simple, sensitive, and rapid, providing a new approach for the rapid detection of LM and other foodborne bacterial pathogens.