Fig. 5: NISDA assay performance.

a Assay response to different dilutions of synthetic SARS-CoV-2 RNA from 100 copies µL⁻¹ to 5 copies µL⁻¹ (blue line: 100; yellow line: 50; red line: 25 and black line: 5) in nucleases free water. b Assay response to different dilutions of synthetic SARS-CoV-2 RNA from 100 copies µL⁻¹ to 10 copies µL⁻¹ (blue line: 100; yellow line: 50; red line: 25 and black line: 10) in oropharyngeal RNA extract, together with their corresponding quantification graphs and dataset based on the calculated signal enhancement slope (Ɵ) and fluorescence readout at 30 min of reaction, respectively. FL, CI, N, and SD denote for fluorescence, confidence interval, negative control, and standard deviation, respectively. c Typical fluorescence kinetics recorded over time for SARS-CoV-2 RNA (10 copies µL⁻¹) and different respiratory viral nucleic acids (500 copies µL⁻¹) spiked in validated CoV-19-negative oropharyngeal RNA extract matrix (Hvidovre Hospital). d Corresponding plot of panel c demonstrating the recorded fluorescence intensities after 30 min of reaction for the studied respiratory viral nucleic acids. Three independent experiments were run (n = 3) and the P values were calculated based on the unpaired two-tailed t test (p < 0.01 for SARS-CoV-2 vs. non-targets; P < 0.001 for SARS-CoV-2 vs. negative matrix). Error bars represent mean value (center line) ± SD. copies µL⁻¹ is the numbers of RNA strands per µL (one copy µL⁻¹ corresponds to five RNA copies per reaction). Source data are provided as a source data file.