Figure 1.
Graphene oxide (GO) entraps the SARS-CoV-2 virus and prevents infection
(A) A schematic representation of the experimental design to assess the ability of GO to trap virus in solution is shown. A SARS-CoV-2 clinical isolate was suspended in phosphate-buffered saline (PBS) at ∼105 virus particles/mL and incubated with increasing concentrations of GO (0.06, 0.12, 0.25, and 0.5 mg/mL) or without GO (untreated) as positive control. Two hours later, GO was removed by centrifugation and supernatants were used to infect VERO cells.
(B) Representative images of VERO cell density taken at 72 h are shown for uninfected cells, SARS-CoV-2-infected cells without GO, and infected cells with medium incubated with increasing concentrations of GO.
(C) Fluorescent microscopic images are shown for VERO cells labeled with an anti-viral spike (S) protein antibody under the same conditions as in (B)
(D–F)(D) Cell viability was also assayed with crystal violet staining, (E) fluorescence, and (F) crystal violet quantification of infected cells and cytotoxicity, respectively.
(G) Lactate dehydrogenase (LDH) was quantified in the cell supernatants to measure SARS-CoV-2-mediated cytotoxicity. Scale bars in B, C, and D are 50 μm. Data are represented as mean ± SD. Statistically significant results are indicated with “∗” according to p value (∗∗p < 0.01; ∗∗∗∗p < 0.0001).