BNR #56 - Pr. Mathieu DENOUAL (GREYC-ENSICAEN, FRA), Oct, 26th 2015, PM5:00- E-lounge

Pr. Mathieu DENOUAL



The talk describes research activities related to the detection of magnetic nanoparticles in 1 dimension and 2 dimensions.

Magnetic nanoparticles (MNPs) are particles with diameters up to 50 nm made of iron, cobalt or nickel. They are
of great interest for a wide range of biotechnological and biomedical applications involving the detection, the trans-
port and the immobilization of magnetically tagged biological entities. Among the specific applications that should be
mentioned, there are: the magnetic particles imaging (MPI ), the magnetic resonance imaging (MRI) contrast enhance-ment, drug/gene delivery, cell separation, biosensing or hyperthermia cancer treatment. For most applications, a high sensitivity magnetic sensor is required for the detection of the magnetic nanoparticles. Several types of magnetic sensors have been used for the detection such as Giant MagnetoResistive (GMR) sensors, spin-valve sensors, fluxgate, SQUID, hall sensors, pickup coil and Giant MagnetoImpedance (GMI).

The integration into a so-called microfluidic microsystem for the detection of flowing nanoparticles often leads to small sensors such as GMR, spin-valve or GMI. The technical challenge of the detection of flowing mag- netic nanoparticles is to develop detection systems that are sensitive enough to detect a single magnetic nanoparticle or clusters of nanoparticles, ideally in a continuous flow. Sensor performance is not the only condi- tion to improve the magnetic nanoparticles detection limit. Indeed, the entire system configuration surrounding the sensor is of importance.