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arXiv · 1403.0866

Room-temperature detection of single 20 nm super-paramagnetic nanoparticles with an imaging magnetometer

Michael Gould·Russell Barbour·Nicole Thomas·Hamed Arami·Kannan M. Krishnan·Kai-Mei Fu
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Abstract

We demonstrate room temperature detection of single 20 nm super-paramagnetic nanoparticles (SPNs) with a wide-field optical microscope platform suitable for biological integration. The particles are made of magnetite (Fe3O4) and are thus non-toxic and biocompatible. Detection is accomplished via optically detected magnetic resonance imaging using nitrogen-vacancy defect centers in diamond, resulting in a DC magnetic field detection limit of 2.3 μT. This marks a large step forward in the detection of SPNs, and we expect that it will allow for the development of magnetic-field-based biosensors capable of detecting a single molecular binding event.

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Michael Gould, Russell Barbour, Nicole Thomas, Hamed Arami, Kannan M. Krishnan, Kai-Mei Fu. 2014-03-04. Room-temperature detection of single 20 nm super-paramagnetic nanoparticles with an imaging magnetometer. https://doi.org/10.1063/1.4893602

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