Conference paper
Chip-Based Measurements of Brownian Relaxation of Magnetic Beads Using a Planar Hall Effect Magnetic Field Sensor
We present a simple 'click-on' fluidic system with integrated electrical contacts, which is suited for electrical measurements on chips in microfluidic systems. We show that microscopic magnetic field sensors based on the planar Hall effect can be used for detecting the complex magnetic response using only the self-field arising from the bias current applied to the sensors as excitation field.
We present measurements on a suspension of magnetic beads with a nominal diameter of 250 nm vs. temperature and find that the observations are consistent with the Cole-Cole model for Brownian relaxation with a constant hydrodynamic bead diameter when the temperature dependence of the viscosity of water is taken into account.
These measurements demonstrate the feasibility of performing measurements of the Brownian relaxation response in a lab-on-a-chip system and constitute the first step towards an integrated biosensor based on the detection of the dynamic response of magnetic beads.
Language: | English |
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Year: | 2010 |
Pages: | 176-183 |
Proceedings: | 8th International Conference on the Scientific and Clinical Applications of Magnetic Carriers |
Series: | Aip Conference Proceedings |
ISSN: | 15517616 and 0094243x |
Types: | Conference paper |
ORCIDs: | Hansen, Mikkel Fougt |