Construction of an electrochemical probe for on chip type flow immunoassay

Mina Okochi, Hiroko Ohta, Tomoyuki Taguchi, Hiroyuki Ohta, Tadashi Matsunaga*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

13 Citations (Scopus)


Miniaturized immunosensors, that combine the analytical power of microfluidic devices with the high specificity of biomolecules, have been intensively studied for clinical analyses, environmental immunoassays and biochemical studies. Protein A has the ability to bind Fc-binding site of immunoglobulin G (IgG), and can be used as the detection probe in immunoassays. Ferrocenecarboaldehyde (Fc-CHO) was labeled to protein A as an electrochemical probe for on chip type amperometric flow immunoassay. When labeling Fc-CHO onto protein A via formation of Schiff-base and its reduction, mean number of nine Fc-CHO labeled to individual protein A molecules. Protein A labeled with Fc-CHO exhibited reversible redox properties of ferrocene in cyclic voltammograms and its peak currents increased with number of labeled ferrocenes. The current response of protein A labeled with Fc-CHO well correlated with its concentration when applying 390 V versus Ag/AgCl. Protein A labeled with Fc-CHO showed sufficient electrochemical properties that are useful in a miniaturized electrochemical immunoassays.

Original languageEnglish
Pages (from-to)952-955
Number of pages4
JournalElectrochimica Acta
Issue number5
Publication statusPublished - 2005 Nov 10
Externally publishedYes


  • Electrochemical probe
  • Ferrocene derivatives
  • Immunoassay
  • Protein A

ASJC Scopus subject areas

  • General Chemical Engineering
  • Electrochemistry


Dive into the research topics of 'Construction of an electrochemical probe for on chip type flow immunoassay'. Together they form a unique fingerprint.

Cite this