Fig. 5.

CECRID deployment for detection of SARS-CoV-2 pseudovirus

(A) Schematic diagram showing the principle and application workflow of CECRID systems.

(B–

D) Comparative analysis of SARS-CoV-2 N gene-bearing pseudovirus detection with CECRID and normal detection platforms. The template and primer set for this LAMP reaction is N#1. Various amount of pseudoviral particles in VTM are collected and viral RNA is purified by commercial RNA purification kit. RT-LAMP is performed with viral RNA at 62 °C for 30 min followed by 20 min of 80 °C inactivation. The purified amplification products (1:50 dilution) are then subjected to AsCas12a-based fluorescence and lateral flow strip detection. For CECRID, L-proline is added in both the LAMP phase and CRISPR detection phase. The endpoint (60 min) fluorescence signal is shown by either bar plot (B), direct visualization (C) or lateral flow strip using biotin-labeled reporter (D). The significant band in test line represents positive result. C: control line. T: test line. (E–G) Similar assays are performed using an independent pseudovirus/template and primer set N #2. Two-way ANOVA test, ****p < 0.0001. ns means not significant. Error bars represent mean ± s.d. (n = 3). a. u., arbitrary unit.