The newly invented COVID-19 saliva test method is portable, cheap, fast and accurate at the same time
The University of Illinois at Urbana- Huimin Zhao, professor of chemistry and biomolecular engineering at the University of Champaign, said he has developed a fast, highly sensitive and accurate detection method, as well as a portable, battery-powered COVID-19 detection device that can be used anywhere and any time . The researchers found that although it is still in the prototype stage, the cost of the device is estimated to be less than $78, and the reagents and other materials required for each test will reach $6-7.
The current coronavirus testing technology is complex, expensive, time-consuming, and requires huge equipment and expert analysts. The new equipment can be loaded with samples and judgements by anyone with minimal training.
This innovation is derived from Zhao’s experiment Lab recently discovered a system for making artificial restriction enzymes, which can be programmed to recognize and cut specific genes in an organism’s genome. In the new device, these enzymes carry DNA guides that mark viral genes of interest. These enzymes cleavage genes are labeled as a dye that will fluoresce only after the genes are cleaved. The resulting fluorescence indicates that these genes are present, which can determine the positive result of COVID-19.
This new technology is called “Scalable Portable Test”, or SPOT for short. It abandons the complicated process of heating and cooling each sample required by many current test schemes to obtain results. SPOT can also detect multiple genes in each sample, making it more accurate than single-gene testing, which may produce incorrect or uncertain results. Another advantage is that it uses saliva, which is easier to collect than nasal swabs and is less invasive.
The research team tested SPOT with 104 clinical saliva samples. They found that it accurately identified 28 of 30 SARS-CoV-2 positive samples and 73 of 74 SARS-CoV-2 negative samples.
Researchers also tested the SPOT device with samples containing influenza virus, coronavirus and three other human coronaviruses. It accurately identifies samples containing the new coronavirus, regardless of whether other viruses are present in the sample.