One-Step Homogeneous Immunoassay for the Detection of Influenza Virus Using Switching Peptide and Graphene Quencher

Abstract

One-step homogeneous immunoassay was developed for detecting influenza viruses A and B (Inf-A and Inf-B) using the switching peptide H2. As the fluorescence-labeled switching peptide dissociated from the binding pocket of detection antibodies, the fluorescence signal could be directly generated by the binding of Inf-A and Inf-B without washing (i.e., one-step immunoassay). For the one-step homogeneous immunoassay with detection antibodies in solution, graphene was labeled with the antibodies as a fluorescence quencher. To test the feasibility of the homogeneous one-step immunoassay, the stability of the antibody complex with the switching peptide was evaluated under different pH and salt conditions. The one-step homogeneous immunoassay with switching peptide was conducted using influenza virus antigens in phosphate-buffered saline and real samples with inactivated Inf-A and Inf-B spiked in serum. Finally, the one-step homogeneous immunoassay results were compared with those of commercially available lateral flow immunoassays.

Defect-Passivated Photosensor Based on Cesium Lead Bromide (CsPbBr3) Perovskite Quantum Dots for Microbial Detection

“…monocytogenes (anti-H. pylori antibodies) isolated from pig and horse sera. , The anti-L. monocytogenes (anti-H.…”

“…For the application of the CsPbBr 3 photosensor in the diagnosis of food poisoning and gastroduodenal disease, an immunoassay was performed using anti-L. monocytogenes (anti-H. pylori antibodies) isolated from pig and horse sera. 69,70 The anti-L. monocytogenes (anti-H. pylori antibody, 20 μg/mL) was immobilized for 2 h at 37 °C and blocked with BSA. Then samples of L. monocytogenes (H. pylori) were incubated with various concentrations (between 10 and 10 7 cells/ mL).…”

A one-step immunoassay based on switching peptides for diagnosis of porcine epidemic diarrhea virus (PEDV) using screened Fv-antibodies

“…In this assay, the results could be obtained by simply mixing samples with Fv-antibodies that were bound to switching peptides. 24,27–30 The switching peptides were synthesized to contain a part of the amino acid sequence of the light chain of IgG, which could specifically bind to the frame region (FR) of Fv-antibodies (V H ). 15,24,27–30 When the S protein was bound to the Fv-antibodies, the pre-bound switching peptides could be quantitatively released from the Fv-antibodies because the binding of the PEDV S protein is stronger than that of the switching peptide to Fv-antibodies.…”

One-step immunoassay based on switching peptides for analyzing ochratoxin A in wines

“…The switching peptides are designed from the structure of IgG. The binding pocket region of IgG is generated via the self-assembly of frame regions (FRs) of the heavy chain (V H ) and light chain (V L ) (Bong et al 2021;Park et al 2022;Sung et al 2022;Kim 2022a). As shown in Fig.…”