Application
Salmonella enterica is responsible for more than half of all food-borne illnesses worldwide. In the US, food safety is ensured by testing for the presence of Salmonella by shipping samples to dedicated laboratories, which involves the use of expensive instrumentation. Researchers at the University of Hawaii at Manoa have developed a novel method based on loop-mediated isothermal amplification (LAMP) that does not require the use of such instruments to detect the presence of Salmonella DNA in milk. As part of this approach, Master Bond EP31 was used to bond the cylinders that housed the phase-change material (PCM) that was responsible for maintaining the reaction temperature of the device.
Key Parameters and Requirements
To detect the presence of Salmonella DNA in samples, the authors’ DNA amplification device needed to maintain a constant reaction temperature for at least 30 minutes to ensure reaction completion. The continuous reactions were heated by adding a small volume of boiling water, and the temperature was maintained for 90 minutes due to the use of a PCM that was housed in an aluminum shell with acrylic caps. Master Bond EP31 was used to fit these pieces together by overnight curing, and then the temperature within the device was measured by using three thermocouples fixed with the epoxy.
Results
The custom-made device successfully maintained the target temperature even longer than was necessary. The authors showed that the fluorescence signal of their custom fluorimeter had comparable performance to real-time PCR. Master Bond’s EP31 played a key role in ensuring that the PCM did not leak from its enclosure, helping the device maintain the temperature required to run the Salmonella DNA amplification reactions. This approach provides a simple approach for detecting Salmonella, especially for developing countries that seek an inexpensive alternative to instrument-based methods due to unreliable electricity grids.