• Media type: E-Article
  • Title: Protein detection with magnetic nanoparticles in a rotating magnetic field
  • Contributor: Dieckhoff, Jan; Lak, Aidin; Schilling, Meinhard; Ludwig, Frank
  • Published: AIP Publishing, 2014
  • Published in: Journal of Applied Physics, 115 (2014) 2
  • Language: English
  • DOI: 10.1063/1.4861032
  • ISSN: 0021-8979; 1089-7550
  • Origination:
  • Footnote:
  • Description: A detection scheme based on magnetic nanoparticle (MNP) dynamics in a rotating magnetic field for a quantitative and easy-to-perform detection of proteins is illustrated. For the measurements, a fluxgate-based setup was applied, which measures the MNP dynamics, while a rotating magnetic field is generated. The MNPs exhibit single iron oxide cores of 25 nm and 40 nm diameter, respectively, as well as a protein G functionalized shell. IgG antibodies were utilized as binding target molecules for the physical proof-of-concept. The measurement results were fitted with a theoretical model describing the magnetization dynamics in a rotating magnetic field. The established detection scheme allows quantitative determination of proteins even at a concentration lower than of the particles. The observed differences between the two MNP types are discussed on the basis of logistic functions.