We describe a microfluidic device for the determination of the concentration of magnetic micro- and nanoparticles, under continuous flow of the carrier fluid, by means of the Giant Magneto-Impedance effect (GMI). The microfluidic chip is composed of a 10 μl chamber situated on top of the GMI sensing material, which is inserted in a microstrip transmission line for the impedance measurements. Tests have been performed using both ferromagnetic and superparamagnetic types of particles in liquid dispersion. The results show a promising sensitivity in the case of the ferromagnetic particles but reveal a great number of detection problems that must be overcame before the prototype become functional.
García-Arribas, A., Martínez, F., Fernández, E., Ozaeta, I., Kurlyandskaya, G., Svalov, A., … Barandiaran, J. M. (2010). GMI magnetic-particle concentration detection in continuous flow. In Procedia Engineering (Vol. 5, pp. 1324–1327). Elsevier Ltd. https://doi.org/10.1016/j.proeng.2010.09.358