Super-sensitive time-resolved fluoroimmunoassay for thyroid-stimulating hormone utilizing europium(III) nanoparticle labels achieved by protein corona stabilization, short binding time, and serum preprocessing

A1 Journal article (refereed)


Internal Authors/Editors


Publication Details

List of Authors: Näreoja T, Rosenholm JM, Lamminmäki U, Hänninen PE
Publisher: SPRINGER HEIDELBERG
Publication year: 2017
Journal: Analytical and Bioanalytical Chemistry
Journal acronym: ANAL BIOANAL CHEM
Volume number: 409
Issue number: 13
Start page: 3407
End page: 3416
Number of pages: 10
ISSN: 1618-2642


Abstract

Thyrotropin or thyroid-stimulating hormone (TSH) is used as a marker for thyroid function. More precise and more sensitive immunoassays are needed to facilitate continuous monitoring of thyroid dysfunctions and to assess the efficacy of the selected therapy and dosage of medication. Moreover, most thyroid diseases are autoimmune diseases making TSH assays very prone to immunoassay interferences due to autoantibodies in the sample matrix. We have developed a super-sensitive TSH immunoassay utilizing nanoparticle labels with a detection limit of 60 nU L-1 in preprocessed serum samples by reducing nonspecific binding. The developed preprocessing step by affinity purification removed interfering compounds and improved the recovery of spiked TSH from serum. The sensitivity enhancement was achieved by stabilization of the protein corona of the nanoparticle bioconjugates and a spot-coated configuration of the active solid-phase that reduced sedimentation of the nanoparticle bioconjugates and their contact time with antibody-coated solid phase, thus making use of the higher association rate of specific binding due to high avidity nanoparticle bioconjugates.


Keywords

Immunoassay interference, Nanoparticle bioconjugate, Nanoparticle protein corona, Sandwich-type immunoassay, time-resolved fluoroimmunoassay

Last updated on 2019-21-07 at 04:53