Dengue fever can be difficult to differentiate from other viral diseases early in its progression. It’s typically diagnosed based on symptoms, but researchers at Singapore’s A*STAR research agency have created a field detector that spots the dengue virus from a drop of saliva.
Not only can it detect the virus, but it’s able to pinpoint whether it’s a secondary infection that often causes dengue hemorrhagic fever or dengue shock syndrome. The test takes about 20 minutes to run and the kit doesn’t require much training to operate.
Within the device are a bunch of channels that move the saliva sample and reagents that prepare it for final mixing with antibody coupled nanoparticles.
Some details about the design of the microfluidic system, according to A*STAR:
As described in the journal Lab on a Chip, the IBN researchers used an innovative stacking flow design to overcome key challenges faced by existing lateral flow designs, such as those used in pregnancy test kits.
In IBN’s device, different flow paths are created for samples and reagents through a multiple stacked system. This allows the saliva sample to flow separately through a fiber glass matrix, which removes the substances that would interfere with the nanoparticle-based sensing system before it mixes with the sensor nanoparticles. IBN’s device configuration also helps to regulate the flow in the test strip, generating uniform test lines for more accurate results.