Vietnamese people invent cheap Covid-19 quick test machine

The domestic research team's mobile Covid-19 screening test machine costs 1/10 of the imported machines, giving results after more than 2 hours.

The device was developed by Master Ngo Quoc Nam (64 years old) and his associates at Phu Sa Biochemistry Company Limited (Can Tho). With 13 years of experience in molecular biology research, in 2018, Mr. Nam and his colleagues developed two lines of integrated PCR and electrophoresis machines, manufactured by Vietnamese technology and exported to Mexico. From this result, in 2020, the research team develops a Spotcheck SC48 reading device that works with a PCR machine to help screen people with Covid-19 at a low cost.

According to the head of the research team, the product has a localization rate of over 80%, the rest is imported chips from abroad. The device has just been appraised by the Ministry of Health and is awaiting approval for a license to circulate in the market.

The operating mechanism of this tester is similar to the Realtime PCR machines currently in use, but different in the optical reading system. The Spotcheck reader with a fluorescent reader acquires a signal at 530 nm emitted by the DNA-Green Dye complex under blue light excitation (450 – 460 nm). After the PCR reaction, the reader analyzes the sample based on the combination of light and temperature. When collecting images of the brightness of each PCR sample at three different temperatures, Spotcheck analyzes and gives final results in four forms: P (Positive – positive), N (Negative – negative), R (Unresolved). – undefined) and E (Error).

According to Mr. Nam, the reading device gives the result only to determine whether the sample is negative or positive, while the quantitative result, ie the concentration of virus (if any) in the sample, the device cannot determine.

The Spotcheck SC 48 device was developed by the team. (Photo: NVCC).

Currently, the testing method of health authorities only needs to use qualitative results to serve isolating treatment and tracing "quantitative results are rarely used, so this product is completely applicable". Mr. Nam said that the reading device can distinguish false negatives caused by chemicals, primers, RNA extraction. and transmit the results to the processing center. The device can directly read the results on the PCR tube, without opening the tube cap to avoid product evaporation after the PCR reaction. Spotcheck can work with existing PCR machines.

Compared with Realtime PCR machines, the read speed of the product is not faster with processing and analysis time from 2 hours to 2.5 hours for 96 plates. However, the cost of buying Realtime PCR testing equipment is about VND 1-2 billion, while the product developed by the team costs only 1/10. In addition, the current test kit biological container must use a refrigerator with a temperature of 2 - 8 degrees Celsius for storage and transportation. The research team's test kit products can be stored at room temperature of 25 degrees Celsius - 35 degrees Celsius without affecting performance.

The research team hopes that the product can reach remote and border areas. because these places do not have the conditions to buy high-cost testing machines. The product helps support these localities to screen for people infected with Covid-19. After having a positive result, these people were immediately isolated. Their patient samples were tested again to show positive results. "A negative test sample gives 100% accurate results, a positive one still has a small error, but the system will not miss a single positive case , " said Mr. Nam.

The product is part of a research project at the Ministry of Science and Technology with a funding of 9 billion VND, a part of the remaining funding is owned by enterprises. Currently, the research team participates in the program Sihub Startup Accelerator - Expara season 3 organized by the Department of Science and Technology of Ho Chi Minh City to seek investment sources and product development partners.