The design of a microfluidic biochip for the rapid,multiplexed detection of foodborne pathogensby surface plasmon resonance imaging

摘要

The rapid detection of foodborne pathogens is increasingly important due to the rising occurrence of contaminated foodsupplies. We have previously demonstrated the design of a hybrid optical device that has the capability to perform real-time surface plasmon resonance (SPR) and epi-fluorescence imaging. We now present the design of a microfluidicbiochip consisting of a two-dimensional array of functionalized gold spots. The spots on the array have beenfunctionalized with capture peptides that specifically bind E. coli 0157:H7 or Salmonella enterica. This array isenclosed by a PDMS microfluidic flow cell. A magnetically pre-concentrated sample is injected into the biochip, andwhole pathogens will bind to the capture array. The previously constructed optical device is being used to detect thepresence and identity of captured pathogens using SPR imaging. This detection occurs in a label-free manner, and doesnot require the culture of bacterial samples. Molecular imaging can also be performed using the epi-fluorescencecapabilities of the device to determine pathogen state, or to validate the identity of the captured pathogens usingfluorescently labeled antibodies. We demonstrate the real-time screening of a sample for the presence of E. coli0157:H7 and Salmonella enterica. Additionally the mechanical properties of the microfluidic flow cell will be assessed.The effect of these properties on pathogen capture will be examined.