Development of a peptide aptamer pair-linked rapid fluorescent diagnostic system for Zika virus detection

A rapid diagnostic system employing an antigen detection biosensing method is needed to discriminate between Zika virus (ZIKV) and Dengue virus (DENV) due to their close antigenic homology. We developed a novel peptide pair-based flow immunochromatographic test strip (FICT) assay to detect ZIKV. Peptide aptamers, P6.1 (KQERNNWPLTWT), P29.1 (KYTTSTLKSGV), and B2.33 (KRHVWVSLSYSCAEA) were designed by paratopes and modified against the ZIKV envelope protein based on the binding affinity. An antibody-free lateral FICT was developed using a pair of peptide aptamers. In the rapid diagnostic strip, the limit of detection (LOD) for the B2.33-P6.1 peptide pair for ZIKV was 2 × 10⁴ tissue culture infective dose TCID₅₀/mL. Significantly, FICT could discriminate ZIKV from DENV. The stability and performance of FICT were confirmed using human sera and urine, showing a comparable LOD value. Our study demonstrated that in silico modeling could be used to develop a novel peptide pair-based FICT assay for detecting ZIKV by a rapid diagnostic test.