Jump to main content
Jump to site search

Issue 16, 2018
Previous Article Next Article

High sensitive and broad-range detection of cortisol in human saliva using a trap lateral flow immunoassay (trapLFI) sensor

Author affiliations

Abstract

Cortisol, a steroid hormone, is a main biomarker of psychological stress. Early diagnosis and proper treatment of such stress is crucial to prevent the excessive secretion of cortisol. However, cortisol has a low molecular weight and cannot provide sufficient recognition sites for sandwich immunoreaction; it has previously been measured using a competitive immunoassay instead of a general sandwich immunoassay. The disadvantage of this approach is that quantitative measurements are limited because of the narrow measurable range that is key for biosensors. To overcome this limitation, we propose a new detection platform that enables small molecules such as cortisol to be quantified with high detection sensitivity. A trap lateral flow immunoassay (trapLFI) sensor has deletion and detection zones instead of the test and control zones in general lateral flow immunoassay (LFI) sensors. The conjugates used to minimize possible detection targets at low concentration are gold nanoparticles that include an antibody against cortisol and an enzyme for signal generation. Target-bound conjugates are captured in the detection zone, whereas conjugates not binding with targets are trapped in the deletion zone. Using this platform, enzyme-catalyzed color signals increase in the detection zone and decrease in the deletion zone with the concentration of cortisol. The ratio of signal from deletion zone and detection zone supplied a wide analytical range (0.01–100 ng mL−1) with high detection sensitivity (9.9 pg mL−1). Analysis of 15 human saliva samples showed a good correlation with conventional ELISA results (R2 = 0.9432).

Graphical abstract: High sensitive and broad-range detection of cortisol in human saliva using a trap lateral flow immunoassay (trapLFI) sensor

Back to tab navigation

Publication details

The article was received on 18 Apr 2018, accepted on 11 Jul 2018 and first published on 13 Jul 2018


Article type: Paper
DOI: 10.1039/C8AN00719E
Citation: Analyst, 2018,143, 3883-3889
  •   Request permissions

    High sensitive and broad-range detection of cortisol in human saliva using a trap lateral flow immunoassay (trapLFI) sensor

    H. Oh, J. Kim, J. Kim and M. Kim, Analyst, 2018, 143, 3883
    DOI: 10.1039/C8AN00719E

Search articles by author

Spotlight

Advertisements