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Flotation Immunoassay: Masking the Signal from Free Reporters in Sandwich Immunoassays.

ABSTRACT: In this work, we demonstrate that signal-masking reagents together with appropriate capture antibody carriers can eliminate the washing steps in sandwich immunoassays. A flotation immunoassay (FI) platform was developed with horseradish peroxidase chemiluminescence as the reporter system, the dye Brilliant Blue FCF as the signal-masking reagent, and buoyant silica micro-bubbles as the capture antibody carriers. Only reporters captured on micro-bubbles float above the dye and become visible in an analyte-dependent manner. These FIs are capable of detecting proteins down to attomole levels and as few as 10(6) virus particles. This signal-masking strategy represents a novel approach to simple, sensitive and quantitative immunoassays in both laboratory and point-of-care settings.

SUBMITTER: Chen H

PROVIDER: S-EPMC4830940 | biostudies-literature | 2016 Apr

REPOSITORIES: biostudies-literature

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Flotation Immunoassay: Masking the Signal from Free Reporters in Sandwich Immunoassays.

Chen Hui H Hagström Anna E V AE Kim Jinsu J Garvey Gavin G Paterson Andrew A Ruiz-Ruiz Federico F Raja Balakrishnan B Strych Ulrich U Rito-Palomares Marco M Kourentzi Katerina K Conrad Jacinta C JC Atmar Robert L RL Willson Richard C RC

Scientific reports 20160414

In this work, we demonstrate that signal-masking reagents together with appropriate capture antibody carriers can eliminate the washing steps in sandwich immunoassays. A flotation immunoassay (FI) platform was developed with horseradish peroxidase chemiluminescence as the reporter system, the dye Brilliant Blue FCF as the signal-masking reagent, and buoyant silica micro-bubbles as the capture antibody carriers. Only reporters captured on micro-bubbles float above the dye and become visible in an ...[more]

PMID: 27075635

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