Currently, the fastest available COVID-19 test kit, the globally acknowledged PCR (Polymerase Chain Reaction), can deliver results within four hours. But Singapore researchers have developed a test kit that is faster than the current standard.
Named Resolute, the test kit delivers results within just two hours, thus reducing the testing time by half. The new kit has been developed in a joint collaboration between the Singapore DSO National Laboratories and the Agency for Science, Technology, and Research (A*STAR).
A standard PCR test takes about an hour to complete but before the test can be done, the swab sample needs to be processed to extract the genetic material — ribonucleic acid (RNA) — using reagents. Since various rounds of "washing" are involved, the process takes long — at least three hours — and so does the entire test.
The Resolute test kit eliminates that washing process. In its Reverse Transcription Polymerase Chain Reaction (RT-PCR) method, the nasal sample is placed into a specifically designed pre-mixed solution before the PCR analysis. Thus, it consumes less time and results can be produced in 60-90 minutes and also decreases the chances of exposure of the virus to the laboratory technicians.
"By eliminating the sample processing step, it reduces the number of steps that the operator needs to handle and potentially the errors that can be introduced during this step," Ng Sock Hoon, Laboratory Director at DSO told media, in a virtual press conference.
She added that the reduction in steps helps in using less manpower and also saves costs. "The cost savings come from the manpower and resources required from RNA extraction. This reduces material and manpower costs, as well as time," she said.
Decreases Human Error
In the traditional PCR test, the washing steps meant it introduced errors. In May, calibration errors led to more than 30 false-positive results from a single lab while last week a Jurong student was wrongly diagnosed with COVID-19 as a result of the complicated process.
But with Resolute, simple processing will eliminate the human errors involved in the process. Hence, it can be used by entry-level lab technicians not well versed with such complicated steps and can be used at any basic laboratory set up. The Resolute test kit will be implemented in all over Singapore in the coming days as the city-state aims to conduct 40,000 tests per day.
The other benefit of the Resolute is that since it does not involve the washing process, it does not need to depend on the processing materials, which are in limited supply as per Dr Weng Ruifen, who is the Chief of product development and project management at DxD Hub.
"With Resolute, we are able to diversify the test kits available, and that we have diversification of raw materials that make us more resilient in the fight against Covid-19. We are then less dependent on one or two suppliers for the test effort," Dr Weng said.
The scientists at DSO and A*STAR are also in the process of the making of Resolute 2.0 which will have improved usability and better performance. In May 2020, A*STAR scientists developed a rapid test kit named cPass which could analyze neutralizing antibodies within an hour.