Integrated System for On-Site Rapid and Safe Screening of COVID-19.

Since the outbreak of coronavirus disease 2019 (COVID-19), the epidemic has been spreading around the world for more than 2 years. Rapid, safe, and on-site detection methods of COVID-19 are in urgent demand for the control of the epidemic. Here, we established an integrated system, which incorporates a machine-learning-based Fourier transform infrared spectroscopy technique for rapid COVID-19 screening and air-plasma-based disinfection modules to prevent potential secondary infections. A partial least-squares discrimination analysis and a convolutional neural network model were built using the collected infrared spectral dataset containing 857 training serum samples. Furthermore, the sensitivity, specificity, and prediction accuracy could all reach over 94% from the results of the field test regarding 968 blind testing samples. Additionally, the disinfection modules achieved an inactivation efficiency of 99.9% for surface and airborne tested bacteria. The proposed system is conducive and promising for point-of-care and on-site COVID-19 screening in the mass population.

Study on flexible surface dielectric barrier discharge plasma film for in situ inactivation of bacteria and viruses

COVID-19 is still pandemic in the world although it has lasted for more than two years, in situ real-time disinfection of curved surfaces in public places is extremely urgent. A flexible plasma film based on surface dielectric barrier discharge is proposed in this study. In situ disinfection effect and the influence of curvature on the performance are studied. The results showed that the film could in situ inactivate a variety of pathogens. Specifically, 10 min plasma treatment results in a log reduction of 3.10, 3.42, and 3.03 for Escherichia coli, Staphylococcus aureus, and vesicular stomatitis virus, respectively. The discharge power and disinfection effect of the film are independent of the curvature, which proves that it can be used for in situ disinfection of curved surfaces. It is speculated that the combined effects of a strong electric field and radical etching physical damage as well as the chemical damage of reactive oxygen and nitrogen species to the protein are the main reasons for the inactivation of pathogens. The inhibition of the film to Omicron type SARS-CoV-2 pseudovirus is 99.3%, and the killing rate to natural bacteria is 94.3%. The film can run for at least 10 h without significant reduction in disinfection effect. In addition, large-scale and digitalization increase the practical potential of a disinfection film. In conclusion, this film is expected to realize in situ real-time disinfection of curved surfaces such as the buttons of the elevator or instrument and door handles, which is of great significance in blocking the spread of COVID-19. [ FROM AUTHOR] Copyright of Applied Physics Letters is the property of American Institute of Physics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all s.)