Capable of large-scale replication at a constant temperature without going through the existing heating-cooling process
Replication method using photothermal nanomaterials, inspection time can be reduced to 5 minutes
The novel coronavirus infection (Corona 19) pandemic, which has been going on for more than three years, has awakened awareness of how an invisible virus can threaten humanity. Vaccines and treatments that suppress transmission and treat patients directly are important, but developing new diagnostic technologies that control the quarantine situation is also essential to respond to future infectious diseases.
Gene amplification (PCR) tests, which were mainly used to respond to Corona 19, have high diagnostic accuracy, but have the disadvantage of being expensive and taking a long time to produce test results. A rapid antigen test, which yields fast results, was also used, but the problem was raised that it did not properly filter out confirmed cases due to its low accuracy, causing confusion in the quarantine system.
According to the scientific community on the 16th, Korean scientists are attracting attention by successively releasing virus diagnostic technologies that overcome the shortcomings of existing diagnostic technologies. Although it fell behind developed countries in the development of vaccines and treatments, it is making remarkable achievements in the development of diagnostic technology.
Ha Taek-jip, a chair professor at Johns Hopkins University in the US, developed a protein processing technology that can replace the existing PCR test and published the research results in the international journal Nature Communications in October last year.
The PCR test used for Corona 19 is a method of replicating the DNA of a sample taken from a suspected confirmed person several times and cooling and heating the gene that identifies the virus on a large scale.
Infection is determined when a gene capable of confirming viral infection is identified above a certain standard in the amplified gene. In the process of temperature cycling from 60 degrees Celsius to 95 degrees Celsius, the inspection takes about 3 to 6 hours. As the number of confirmed cases increased, it took almost 10,000 days for the examinee to find out if the test was confirmed.
Professor Ha’s research team succeeded in amplifying genes at a single temperature to shorten the time required for cooling and heating in conventional PCR tests. It is a new source technology of ‘engineered helicase’ that causes mutations in genes so that replication can occur stably without temperature change.
In order to replicate a gene, the twisted structure must be unwound through heating and then completely separated into two strands through a process of cooling. Professor Ha’s research team grafted single-stranded DNA-binding protein (SSB), which has the property of maintaining the stability of a single-stranded form even after separation, with genetic modification technology that promotes the separation process without temperature change. Using this technique, it is possible to clone genes at a single temperature of 65 degrees. In a COVID-19 virus detection experiment using this technology, the same results as the conventional PCR test were obtained, proving its accuracy.
Ji-min Kang, a researcher at Johns Hopkins University who participated in the study, said, “It reduces protein damage during the heating process and reduces the time required for the cooling process to quickly provide accurate test results.” It is very cheap,” he explains.
Researchers at the Korea Institute of Science and Technology (KIST) also unveiled a technology that can drastically reduce the time required for PCR testing. Kim Sang-gyeong, head of the Center for Safety Enhancement and Convergence Research at KIST (Principal Researcher at KIST), published a research result in the international academic journal ‘ACS Nano’ last month that reduced the time required for inspection to five minutes by using photothermal nanomaterials. The core of this technology is the use of photothermal nanomaterials that quickly generate high heat immediately upon exposure to light, instead of the conventional method of using a hot plate for temperature circulation. KIST is currently developing a miniaturization technology to introduce this technology to the actual medical field.
In addition, technologies capable of rapid diagnosis are also emerging. A research team led by Marton Merks at the Eindhoven University of Technology in the Netherlands developed a technology to quickly and easily diagnose diseases by causing a luminescent effect on a virus and published it in the international journal ‘ACS Central Science’ on the 15th (local time). The research team utilized ‘luciferase’, a protein that exists in fireflies and phytoplankton and produces a luminous effect at night. This protein was corrected to emit light when combined with the viral gene using gene scissors technology. The sensor developed in this way succeeded in detecting SARS-CoV-2, which causes Corona 19, in 20 minutes from a sample taken from a nasal swab.
Donga Science Reporter Park Jeong-yeon hesse@donga.com
