Dithiobis(succinimidyl propionate) modified gold microarray electrode based electrochemical immunosensor for ultrasensitive detection of cortisol

Biosens Bioelectron. 2010 Jun 15;25(10):2296-301. doi: 10.1016/j.bios.2010.03.016. Epub 2010 Mar 18.

Abstract

Gold microelectrode arrays functionalized with dithiobis(succinimidyl propionate) self-assembled monolayer (SAM) have been used to fabricate an ultrasensitive, disposable, electrochemical cortisol immunosensor. Cortisol specific monoclonal antibody (C-Mab) was covalently immobilized on the surface of gold microelectrode array and the sensors were exposed to solutions with different cortisol concentration. After C-Mab binding, unreacted active groups of DTSP were blocked using ethanol amine (EA) and label-free electrochemical impedance (EIS) technique was used to determine cortisol concentration. EIS results confirmed that EA/C-Mab/DTSP/Au based biosensor can accurately detect cortisol in the range of 1pM-100nM. The biosensor was successfully used for the measurement of cortisol in interstitial fluid in vitro. This research establishes the feasibility of using impedance based biosensor architecture for disposable, wearable cortisol detector.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biosensing Techniques / instrumentation*
  • Conductometry / instrumentation*
  • Equipment Design
  • Equipment Failure Analysis
  • Gold / chemistry*
  • Humans
  • Hydrocortisone / blood*
  • Immunoassay / instrumentation*
  • Microarray Analysis / instrumentation*
  • Microelectrodes*
  • Reproducibility of Results
  • Sensitivity and Specificity
  • Succinimides / chemistry*

Substances

  • Succinimides
  • Gold
  • dithiobis(succinimidylpropionate)
  • Hydrocortisone