Fig. 6: SynBioNF-enabled SERS screening of clinical samples for COVID-19 patient screening.
a, Representative Raman images of identified three positive (P1–P3) and three negative (N1–N3) samples. The red colour indicates the presence of SCV2 on the gold microelectrodes, which clearly differentiates the positive samples from the negative controls. Data from three independent experiments. b, Raman intensities of all the clinical samples, with the horizontal lines showing the mean values (n = 134 biologically independent samples) (p < 0.0001, two-tailed t-test). c, Classification result of SynBioNF-based SCV2 detection with the use of the cut-off value (that is, 94) and correlation with RT-qPCR diagnosis. d, Receiver operating characteristic curve of patient versus healthy detection. AUC, area under the curve. e, Bland–Altman plot of SynBioNF-enabled and RT-qPCR detection. f, Raman intensities for the detection of SCV2 Delta variant, Omicron variant and healthy clinical sample controls, with the horizontal lines showing the mean values (n = 21 biologically independent samples) (p < 0.0001, two-tailed t-test). g,h, Detection of healthy samples spiked with different concentrations of SCV2 virions showing Raman intensities with Ct values labelled on the top of the columns (g) and the corresponding commercially available LFA photographs (h), in which LFA failed to generate visible signals on the use of SCV2 concentration lower than 2 × 104 virions ml–1.
