Fig. 3.

Pathogen inactivation. (A), Schematic illustration of the pathogen inactivation module, which contains 2 infrared bulbs under the cover, a tube holder that sits 16 collection tubes, a Peltier element attached under the tube holder, and a control panel. (B), Temperature profiles of the upper part of 16 collection tubes by infrared heating. (C), Inactivation of pseudoviruses SARS-CoV-2 and MERS-CoV in preservation buffer using mode 1. (D), Inactivation of pseudovirus MERS-CoV smears in the upper sidewalls and caps using mode 2. In (C) and (D), the negative control refers to cell-plated microwells that do not contain virus samples, and the noninactivated groups refer to cell-plated microwells that contain virus samples that did not go through the inactivation process. The numbers and color codes in the charts represent the magnitude of fluorescent signals in luciferase assay. a.u., arbitrary units. (E), RT-qPCR amplification results of pseudovirus FNV-2019-ncov-abEN at the concentrations of 5E3 copies/mL after inactivation at different conditions (n = 3). Noninactivated pseudovirus FNV-2019-ncov-abEN was used as a control to check the integrity of treated nucleic acids. In group 1, the collection tubes containing pseudovirus samples were heated in the water bath at 56 °C for 30 min, whereas in groups 2, 3, and 4, the upper part of tubes was heated at 95 °C while the lower part was heated at 56 °C for 30 min, 70 °C for 12 min, and 95 °C for 12 min, respectively. Ct, threshold cycle.