Fig. 4

Characterization of the SARS-CoV-2 enzyme-linked aptamer-antibody sandwich assay and hybrid lateral flow strip. A Standard curves of the hybrid ELAAA ( ) and traditional double antibodies-based ELISA ( ) for the N protein standard. The results represent the mean ± SD of absorbance value obtained from three independent replicates. B The visual detection limit of the hybrid-LFS for the N protein standard in the extraction solution. C The visual detection limit of the traditional double antibodies-based immunostrip for the N protein standard in the extraction solution. D Standard curves of the test line intensity on the hybrid-LFS ( ) and traditional antibodies-based immunostrip ( ). The results represent the mean ± SD of test line intensity (RLU) obtained from three independent replicates