Recent progress in homogeneous immunosensors based on fluorescence or bioluminescence using antibody engineering

Abstract

Homogeneous immunosensors integrate the advantages of both biosensors and immunoassays; it includes speed, high sensitivity, and accuracy. They have been developed rapidly in the past few years and offer a...

Quenchbodies That Enable One-Pot Detection of Antigens: A Structural Perspective

“…Fluorescent immunosensors, which are produced by conjugating fluorescent probes to the antibody, have been widely studied owing to their ease of handling, high sensitivity, and rapid assay time [1,2]. Reagentless fluorescence immunoassay, which comprises homogeneous fluorescent antibodies, whose fluorescence changes due to binding to a target antigen, has been developed [3][4][5]. Reagentless fluorescence immunoassay requires only a few minutes to quantify the target antigen as the steps of washing, blocking, and incubation with secondary and/or tertiary antibodies are eliminated.…”

Generation of a Recombinant scFv against Deoxycholic Acid and Its Conversion to a Quenchbody for One-Step Immunoassay

“…The versatility of fluorescence immunoassays has been widely expanded [10,11]. Among them, reagent-free fluorescence immunoassays offer the advantage of rapid and convenient measurements, which are comparable to traditional ELISA [12][13][14]. Reagent-free fluorescence immunoassays only require a few minutes for the full procedure composed of the single-step reaction of the fluorescent antibody and antigen because there is no need for additional steps, such as immobilization, washing, and secondary/tertiary antibody reactions.…”

Special Issue “Immunoanalytical and Bioinformatics Methods in Immunology Research”

“…The physical adsorption and covalent binding of antibodies are commonly used immobilization methods; however, site-directed immobilization of native antibodies, for instance, using proteins A and G, provides increased sensitivity [11]. Moreover, the use of reduced antibody fragments may be a possible alternative for the site-directed orientation of antigen-binding sites of antibodies developing sensitive immunosensors and other immunoanalytical methods [12]. The affinity of used antibodies or their fragments towards antigens is highly important for improving the performance of the immunoanalytical system.…”