Microfluidic microsystem for magnetic sensing of nanoparticles with giant magneto-impedance technology

Matthieu Denoual (1) , M. Harnois (2) , Sébastien Saez (1) , Christophe Dolabdjian (1) , V. Senez (2)

1 Equipe Electronique - Laboratoire GREYC - UMR6072
2 IEMN - Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520

We have fabricated a microfluidic microsystem integrating a Giant Magneto-Impedance wire sensor that successfully detected the passage of magnetic nanoparticules in liquid medium. Giant Magneto-Impedance microwire sensors consisted in CoFeSiBNb alloy, 40 μm diameter and 1 cm long wires. By magnetizing the magnetic nanoparticles in the liquid perpendicularly to the sensitive axis of the Giant Magneto-Impedance microwire sensor, we have observed magneto-impedance signal variations induced by the magnetic dipole field from the magnetic nanoparticles. A peak detector was used to measure the voltage signal due to the magneto-impedance variations. The voltage signal was subsequently demodulated by a lock-in amplifier.

Mots clés: microsystem; microfluidic; magnetic nanoparticles; magnetic sensor; Giant Magneto-Impedance (GMI)

Domaines: Electromagnétisme

Matthieu Denoual, M. Harnois, Sébastien Saez, Christophe Dolabdjian, V. Senez. Microfluidic microsystem for magnetic sensing of nanoparticles with giant magneto-impedance technology. 16th International Conference on Solid-State Sensors, Actuators and Microsystems, TRANSDUCERS'11, 2011, Beijing, China. pp.80-83, ⟨10.1109/TRANSDUCERS.2011.5969140⟩. ⟨hal-00800386⟩