Title :
A Novel Zero-Drift Detection Method for Highly Sensitive GMR Biochips
Author :
Han, S.-J. ; Xu, L. ; Wilson, R.J. ; Wang, S.X.
Author_Institution :
Dept. of Mater. Sci. & Eng., Stanford Univ.
Abstract :
In this paper, we present a novel drift compensation mechanism for highly sensitive biodetection based on giant magnetoresistive (GMR) sensors and magnetic nanoparticles. Micromagnetic simulations showed the quantitative detection ability of this new method. The proposed detection scheme uses both ac current sources and ac magnetic fields along with two dc bias states. Experiments were carried out to detect Miltenyi Biotec (MACS) magnetic nanoparticles on the spin-valve sensor (0.2 mumtimes4 mum). The experimental results show that sub-microvolt drifts can be achieved by this dual bias-double modulation (DBDM) method
Keywords :
biosensors; giant magnetoresistance; magnetic particles; magnetic sensors; nanoparticles; spin valves; GMR biochips; ac current sources; ac magnetic fields; drift compensation; giant magnetoresistive sensors; miltenyi biotec magnetic nanoparticles; spin-valve sensor; zero-drift detection; Biosensors; Electromagnetic interference; Giant magnetoresistance; Immune system; Magnetic field measurement; Magnetic sensors; Magnetization; Micromagnetics; Nanoparticles; Temperature sensors; Biosensor; micromagnetic simulation; spin-valve; temperature drift cancellation;
Journal_Title :
Magnetics, IEEE Transactions on
DOI :
10.1109/TMAG.2006.879615
