A microfluidic lab-on-a-disc integrated loop mediated isothermal amplification for foodborne pathogen detection

Salmonellosis is one of the most common foodborne diseases caused by the genus Salmonella and is considered to be a significant global health concern. Therefore, the development of effective techniques for rapidly detecting Salmonella is fundamental in preventing foodborne outbreaks. This paper presents a lab-on-a-disc integrated loop mediated isothermal amplification (LAMP) on a microfluidic platform for Salmonella detection. We have developed a centrifugal microfluidic platform device in which the main steps in pathogen detection, reagent preparation, LAMP, and detection can be integrated onto a single microfluidic compact disc (CD). A forced convection heating source was used for wax valve actuation and temperature heating for the LAMP amplification, leading toward compactness and system miniaturization. The detection limit was 5 × 10−3 ng/μL DNA concentration when tested on tomatoes spiked with Salmonella. The whole procedure, from sample preparation (on the microfluidic CD) up to detection, was completed within 70 min using a fully automated process. The final detection step was performed via direct visual observation of the color change of the SYBR Green I dye. Our system offers a fast and automated molecular diagnostic platform, thereby reducing the need for skillful operators and expensive instrumentation. This developed portable device would have a wide range of potential biomedical applications, including foodborne pathogen detection and molecular diagnostics in developing countries.