Magnetic particle detection by frequency mixing for immunoassay applications |
| |
| Authors: | Hans-Joachim Krause,Norbert Wolters,Yi Zhang,Andreas Offenhä usser,Peter Miethe,Martin H.F. Meyer,Markus Hartmann,Michael Keusgen |
| |
| Affiliation: | 1. Institute of Bio and Nano Systems, IBN-2: Bioelectronics, and CNI – Center of Nanoelectronic Systems for Information Technology, Forschungszentrum Jülich, 52425 Jülich, Germany;2. Senova Gesellschaft für Biowissenschaft und Technik mbH, Winzerlaer Str. 2, 07745 Jena, Germany;3. Institute for Pharmaceutical Chemistry, University of Marburg, Marbacher Weg 6, 35032 Marburg, Germany |
| |
| Abstract: | For magnetic immunoassay applications, a novel magnetic reader for quantification of magnetic particle concentrations has been developed. Upon magnetic excitation at two distinct frequencies incident on the sample, the response signal generated at a sum frequency is detected. The low-frequency field component periodically drives the magnetic particles into saturation, which is probed by the high-frequency field. The appearance of frequency mixing lines is highly specific to the nonlinearity of the superparamagnetic particles’ magnetization. The optimization of field coils, differential pickup coil, preamplifier, demodulators and filters are discussed. The output signal is linear for four orders of magnitude in iron concentration. |
| |
| Keywords: | Magnetic detection Frequency mixing Superparamagnetism Nonlinearity Induction coil Immunoassay |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
