Can a mobile phone be used to detect novel Coronavirus?Not only can it, but it’s fast and accurate. What’s the point?
A timely and reliable Novel Coronavirus test has long puzzled us.”Gold standard” PCR nucleic acid detection sensitivity is high, but the demand is large, the detection procedure is complex, the detection results are often not timely;Rapid antigen tests, while giving us faster results, are far less sensitive than PCR.So is there a way to do that that’s as fast as the rapid antigen test, that’s as accurate as the PCR test?A recent paper in JAMA, one of the world’s four top medical journals, offers a novel Coronavirus test: one that can be tested quickly and accurately at home using only saliva samples, smartphones and inexpensive diagnostic kits.If this method can be promoted, it will be of great significance for the prevention and control of the epidemic.The “gold standard” PCR nucleic acid test is to detect the Novel Coronavirus, first of all to find out what is unique about the Novel Coronavirus, and then to amplify that unique to the extent that we can observe it.So what is unique about Novel Coronavirus?The viral genome (nucleic acid) and viral proteins are what make it special.The “gold standard” PCR test is the nucleic acid of the virus. It is a novel Coronavirus genome-based test that uses PCR to amplify the Novel Coronavirus gene fragments in a sample until there are enough of them for our machines to detect.If they detect it, they have it, if they don’t, they don’t. Simple as that.PCR can be used to amplify a single gene fragment of the virus over and over again, so it can be sensitive enough to detect the virus in a sample with a few more amplitions.And the virus genome is special, so the specificity of nucleic acid tests can be very good as long as they are properly designed.It is for this reason that nucleic acid testing is known as the “gold standard” of novel Coronavirus testing.”Quick screen” virus protein detection but nucleic acid detection is not perfect, this detection method to use special equipment, the time of its own detection experiment is relatively long, but also queue to collect samples, and then sent to do nucleic acid detection.As we know, there are too many cases abroad. If all nucleic acid tests are performed by PCR, the test pressure will be very high and the test results will take a long time.So a rapid test, called a quick screen, or antigen test, has emerged, which tests directly for the proteins of the virus.Unlike PCR, which does not replicate amplified proteins, rapid screening uses antibodies that bind to virus-specific proteins to catch the virus and then, through biochemical reactions, amplify the signal to the point where we can see it.Antigen detection is fast, simple and does not require special equipment.However, unlike PCR, which has the ability to amplify virus fragments, the sensitivity of antigen detection is poor, and the virus quantity can only be detected when it is relatively high, which is not conducive to early detection. When it can be detected, the infectivity of the infected person is often very high.The good news, however, is that jAMA recently reported ona new system developed by US researchers for detecting Novel Coronavirus and influenza virus infections. The smart Light system is based on real-time loop-mediated isothermal amplification for smartphones.Loop-mediated isothermal amplification is similar to PCR in that it uses primers and polymerase etc. to amplify the DNA of the virus, which will detect if the Novel Coronavirus DNA is present in the sample.But because the influenza and Novel Coronavirus genomes are made of RNA, there is a step called reverse transcription that converts RNA into DNA before it can be amplified, which is similar to PCR detection.However, unlike PCR, which works at a constant temperature by heating the sample to a very high temperature to separate the DNA strand, lowering the temperature to allow the primer to bind to the exposed DNA, then raising the temperature slightly again to allow the DNA to be amplified, and repeating the process over and over again.This means that PCR requires specialized and expensive thermal cycling equipment, whereas this method requires only a module that can maintain a constant temperature.Moreover, the smart light system uses a smartphone camera and an app to detect the presence of the target virus in saliva samples. The method is known to return results within 25 minutes, and according to the authors of the paper, the results of the smart light system test match the PCR results exactly.We believe that if this method can achieve rapid and accurate detection of novel Coronavirus as mentioned by the authors of this paper, it will be of great significance for our epidemic prevention and control.In an article written before Kunartech Sauce, “Why Can’t We Eradicate Novel Coronavirus? How Effective are Vaccines and What can we do about it?”We mentioned that whether a virus can be eradicated has three characteristics: first, effective measures to prevent the spread of the virus;Second, diagnostic tools that can quickly detect infections are readily available;Finally, there is no disease caused by this virus in animals other than humans.If we can achieve rapid detection of the virus, then we have the opportunity to effectively reduce the risk of omicron infection in a variety of ways.Good public health is the key. Novel Coronavirus is a serious threat. What should we do?To build a “four-dimensional protection shield” or way out) to prevent the spread of the virus, and ultimately control the spread of the virus, is of great significance.What do you think about that?Welcome to leave a message.I am the senior operation of Guona Technology Sauce, technical background, the contracted creator of hundred originality plan, the creator of hundred list and preferred plan, rooted in the field of air cleaning/new materials/energy conservation and environmental protection for twenty years, with a calm and professional perspective to bring you different scientific cognition.Important disclaimer: The article published here is the author of the original work of China National Science and Technology sauce, the copyright belongs to China National Science and technology sauce, the picture comes from the Internet.Reprint please indicate the original author and source!