Fluidic Devices Involving Signal Generation at Converging Fronts
Dr. Charles Mace has designed a novel multilayered paper device. First, liquid sample is transported to chambers within the device with stored reagents. Then the liquid mixtures from the chambers converge back to a reaction zone. The converging liquid fronts generate a signal that, through design and specific paper treatments, restrict signal generation to a well defined interface.
Most commercially successful paper-based microfluidic devices are lateral flow test strips (e.g. home pregnancy test). In these devices, labeled analyte is captured on a strip of immobilized reagent (e.g. antibody) to produce a colored band of signal for the user to read.
However, many important analytes cannot be captured by an antibody. Further, if signal cannot be immobilized, the colorimetric readout diffuses throughout the entire patterned zone (typically circular), thus resulting in non-uniform color distribution away from the center of the reaction.
These signal immobilization difficulties exclude a significant number of diagnostic assays from commercial availability.
This platform technology has the ability to significantly diversify the types of analytes that can be detected in point-of-care diagnostic assays. Tufts University is looking for a commercial partner to further develop this technology and expand the capabilities of existing paper-based diagnostics. In doing so, this partnership will likely create several new consumer products. No capture agent; improved visualization and uniform signal distribution.
Dr. Mace’s group has used this platform to detect a physiological concentration (10mM) of glucose. For this application, only two reagent chambers are necessary – one with glucose oxidase and the other with a mixture of potassium iodide and horseradish peroxidase. The signal generated is a brown line at the interface of the two advancing liquids.
• Simple design
• Incompatible reagent storage
• High sensitivity
Provisional Application Filed