Singapore researchers were able to develop a paper test to test dengue in 20 minutes, reducing the time taken and the pain of a needle to extract blood sample for the traditional test.
The Institute of Bioengineering and Nanotechnology (IBN) of Singapore has developed the paper-based disposable device that can detect dengue-specific antibodies from saliva within 20 minutes.
Professor Jackie Y. Ying said, “Our rapid diagnostic kit can detect a key dengue antibody from saliva that is present in early-stage secondary infection. The ability to differentiate between primary and secondary dengue infections makes it a valuable early diagnosis tool that would help to ensure timely treatment and proper care of patients.”
The test helps patients with secondary infection, who have previously been infected with other serotypes of dengue virus, stand a higher risk of developing dengue hemorrhagic fever or dengue shock syndrome.
Dengue fever and dengue hemorrhagic fever are the most common mosquito-borne viral diseases in the world now and it is a leading cause of illness and death in tropical and subtropical climates. Dengue has four known serotypes but no vaccine has been developed so far.
The incubation period before symptoms develop generally ranges from 4 to 10 days after infection, making it difficult to diagnose the patient early and to avoid further complications.
Currently, dengue is diagnosed by testing the patient’s blood sample for dengue antigens or antibodies. But with the IBN’s device detecting IgG, a dengue-specific antibody found at the onset of secondary infections, is possible in 20 minutes directly from saliva in one step.
Published in the journal ‘Lab on a Chip’, the IBN researchers said they had 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 with different flow paths for samples and reagents through a multiple stacked system 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.
IBN’s diagnostic kit can also be adapted to detect other infectious diseases such as HIV and Syphilis and the IBN researchers are exploring the use of other common fluid samples, such as blood, urine and serum for rapid, high-sensitivity test kits.
The Institute is currently collaborating with Japanese firm ARKRAY Inc. to commercialize its paper-based diagnostic technology. Atsushi Murakami, General Manager of the R&D Division of ARKRAY, said: “We will continue to focus on the successful commercialization of new technologies for the diagnosis of tropical infectious diseases.”