Abstract

Salmonella DNA-Fingerprinting using Lab-on-Chip

Pulsed-field Gel Electrophoresis

Salmonella is a foodborne pathogen and one of the leading causes of reported illnesses. Annually, in the United States, it is estimated to cause one million illnesses resulting in 19,000 hospitalizations and 380 deaths. Improving diagnostic testing for Salmonella can help in early detection and treatment, and thereby prevent serious illness and even death. One of the current methods of detection of pathogens is to create a unique DNA band pattern or “fingerprint” to identify them using traditional gel electrophoresis methods. This approach is time consuming, complex, and expensive. Further, people in less developed countries may not have access to such complex diagnostic methods. Hence, the objective of this study is to design and test a fast and low-cost method using a microfluidic lab-on-chip to detect Salmonella by creating a DNA-fingerprint. The first research hypothesis of this study is that pulsed-field gel electrophoresis can be implemented in a microfluidic environment of a lab-on-chip. For this, a microfluidic lab-on-chip was designed, fabricated, and tested successfully using nanoparticles, to demonstrate that pulsed-field gel electrophoresis may be used for DNA fingerprinting in this environment. The second research hypothesis of this study is that this lab-on-chip design and method could then be used to detect Salmonella. The microfluidic lab-on-chip developed in this study successfully implemented pulsed-field gel electrophoresis to create a Salmonella DNA-fingerprint within three minutes. This study showed that it is feasible to develop fast and low-cost microfluidic lab-on-chip solutions to detect foodborne pathogens.