Detection of magnetic nanoparticles with superconducting quantum interference device (SQUID) magnetometer and application to immunoassays

Keiji Enpuku, Tadashi Minotani, Takemitsu Gima, Yukinori Kuroki, Yuzuru Itoh, Makiko Yamashita, Yoshinori Katakura, Satoru Kuhara

Research output: Contribution to journalArticle

124 Citations (Scopus)

Abstract

A system is developed to magnetically measure biological antigen-antibody reactions with a superconducting quantum interference device (SQUID) magnetometer. In this system, antibodies are labeled with magnetic nanoparticles of γ-Fe2O3, and the antigen-antibody reactions are measured by detecting the magnetic field from the magnetic nanoparticles. A setup of the system is described, and the sensitivity of the system is studied in terms of detectable weight of nanoparticles. Magnetic particles as small as 600 pg can be detected at present. An experiment is also conducted to measure antigen-antibody reaction with the present system. It is shown that the sensitivity of the present system is better than that of the conventional optical method. A one order of magnitude improvement of sensitivity will be realized by the sophistication of the present system.

Original languageEnglish
Pages (from-to)L1102-L1105
JournalJapanese Journal of Applied Physics, Part 2: Letters
Volume38
Issue number10 A
DOIs
Publication statusPublished - 1999

All Science Journal Classification (ASJC) codes

  • Engineering(all)
  • Physics and Astronomy (miscellaneous)
  • Physics and Astronomy(all)

Fingerprint Dive into the research topics of 'Detection of magnetic nanoparticles with superconducting quantum interference device (SQUID) magnetometer and application to immunoassays'. Together they form a unique fingerprint.

Cite this