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Microfluidic Platform for Magnetic Nanoparticle Trapping and Detection



Charles A. Little, John Pellegrino, Stephen E. Russek


We evaluate giant magnetoresistance (GMR) sensors to trap and count small concentrations of magnetic nanoparticles (MNPs) within microfluidic flow. The device presented in this paper takes the novel approach of capturing and detecting MNPs utilizing the strong fringe-fields present on the periphery of the patterned sensor. The presence of MNPs manifests as a field shift in magnetoresistance (MR) curve. Tests of the device have shown a noticeable response for 30 nm nominal MNPs at a flow rate of 5 υL/min. Such a device would be beneficial for a number of bio-medical applications, including immunoassays and for monitoring filtration processes, where large sample fluid volumes and lowering MNP concentration sensitivities are required.
IEEE Transactions on Magnetics


Giant magnetoresistance, Magnetic particles, Magnetic sensors, Microfluidics


Little, C. , Pellegrino, J. and Russek, S. (2013), Microfluidic Platform for Magnetic Nanoparticle Trapping and Detection, IEEE Transactions on Magnetics, [online], (Accessed June 13, 2024)


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Created July 15, 2013, Updated November 10, 2018