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A Wash-Free Homogeneous Colorimetric Immunoassay Method.

ABSTRACT: Rapid and convenient biosensing platforms could be beneficial to timely diagnosis and treatment of diseases in virtually any care settings. Sandwich immunoassays, the most commonly used methods for protein detection, often rely on expensive tags such as enzyme and tedious wash and incubation procedures operated by skilled labor. In this report, we revolutionized traditional sandwich immunoassays by providing a wash-free homogeneous colorimetric immunoassay method without requirement of any separation steps. The proposed strategy was realized by controlling the growth of gold nanoparticles (AuNPs) to mediate the interparticle spacing in the protein-AuNP oligomers. We have demonstrated the successful in vitro detection of cancer biomarker in serum samples from patients with high clinical sensitivity and specificity.

SUBMITTER: Liu H

PROVIDER: S-EPMC4679354 | biostudies-literature | 2016

REPOSITORIES: biostudies-literature

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A Wash-Free Homogeneous Colorimetric Immunoassay Method.

Liu Huiqiao H Rong Pengfei P Jia Hongwei H Yang Jie J Dong Bo B Dong Qiong Q Yang Cejun C Hu Pengzhi P Wang Wei W Liu Haitao H Liu Dingbin D

Theranostics 20160101 1

Rapid and convenient biosensing platforms could be beneficial to timely diagnosis and treatment of diseases in virtually any care settings. Sandwich immunoassays, the most commonly used methods for protein detection, often rely on expensive tags such as enzyme and tedious wash and incubation procedures operated by skilled labor. In this report, we revolutionized traditional sandwich immunoassays by providing a wash-free homogeneous colorimetric immunoassay method without requirement of any separ ...[more]

PMID: 26722373

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