The Governing Council of the University of Toronto

Published purpose

The recipient proposes to optimize and perform a proof of concept study that combines microfluidic and molecular assay that detect SARS-CoV-2 from saliva by a color change in 30 minutes with minimum sensitivity of 10-18 mol. The microfluidic system will contain compartments with different steps of the assay. This assay consists of reagents that aim to amplify the SARS-CoV-2 genetic material (e.g. E gene) by 10 thousand fold. The amplified genetic material should bind to 13-nm gold nanoparticles coated with complementary single stranded DNA. The color of the solution should change because the gold nanoparticle will be assembled onto the SARS-CoV-2 amplified gene. The clustering of the gold nanoparticle changes how the electrons move leading to different absorbance properties. This physical process can be visualized by the change in the solution color from red to blue of the gold nanoparticles. A positive detection occurs when the solution is blue. The team propose to develop a microfluidic chip where different chambers to control each of the diagnostic assay reactions. The team will load diagnostic formulations (consist of enzymes, salts, and gold nanoparticle-conjugates) in each chamber. Individual reactions will occur by flowing the liquid from one chamber to the next in a consumable device that can be actuated with the use of an instrument in the simplest implementation.