Fluorometric determination of heparin based on self-quenching of fluorescein-labeled protamine

Yuya Egawa, Ryosuke Hayashida, Toshinobu Seki, Jun ichi Anzai

Research output: Contribution to journalArticlepeer-review

36 Citations (Scopus)


A new signaling technique for a fluorometric heparin assay has been developed using the self-quenching of fluoresceinisothiocyanate-labeled protamine (F-protamine). The binding between F-protamine and heparin led to a significant fluorescence quenching due to enhancing the proximity of the F-protamine molecules. The fluorescence of F-protamine (5.9 μg/mL) decreased to 13% in the presence of 2.0 μg/mL heparin. An advantage of this self-quenching system is that the detection can be carried out without using other indicators. With the present system, we could monitor the therapeutic level of heparin in bovine plasma, and the response was quick. These properties of the self-quenching system are suitable for practical use.

Original languageEnglish
Pages (from-to)736-741
Number of pages6
Issue number4
Publication statusPublished - 2008 Aug 15


  • Fluorescein
  • Fluorescence
  • Heparin
  • Protamine
  • Self-quenching

ASJC Scopus subject areas

  • Analytical Chemistry


Dive into the research topics of 'Fluorometric determination of heparin based on self-quenching of fluorescein-labeled protamine'. Together they form a unique fingerprint.

Cite this