The Scanning TMR Microscope for Biosensor Applications
AbstractWe present a novel tunnel magnetoresistance (TMR) scanning microscopeset-up capable of quantitatively imaging the magnetic stray field patterns of micron-sizedelements in 3D. By incorporating an Anderson loop measurement circuit for impedancematching, we are able to detect magnetoresistance changes of as little as 0.006%/Oe. By 3Drastering a mounted TMR sensor over our magnetic barcodes, we are able to characterisethe complex domain structures by displaying the real component, the amplitude and thephase of the sensor’s impedance. The modular design, incorporating a TMR sensor withan optical microscope, renders this set-up a versatile platform for studying and imagingimmobilised magnetic carriers and barcodes currently employed in biosensor platforms,magnetotactic bacteria and other complex magnetic domain structures of micron-sizedentities. The quantitative nature of the instrument and its ability to produce vector maps ofmagnetic stray fields has the potential to provide significant advantages over other commonlyused scanning magnetometry techniques. View Full-Text
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Vyas, K.N.; Love, D.M.; Ionescu, A.; Llandro, J.; Kollu, P.; Mitrelias, T.; Holmes, S.; Barnes, C.H.W. The Scanning TMR Microscope for Biosensor Applications. Biosensors 2015, 5, 172-186.
Vyas KN, Love DM, Ionescu A, Llandro J, Kollu P, Mitrelias T, Holmes S, Barnes CHW. The Scanning TMR Microscope for Biosensor Applications. Biosensors. 2015; 5(2):172-186.Chicago/Turabian Style
Vyas, Kunal N.; Love, David M.; Ionescu, Adrian; Llandro, Justin; Kollu, Pratap; Mitrelias, Thanos; Holmes, Stuart; Barnes, Crispin H.W. 2015. "The Scanning TMR Microscope for Biosensor Applications." Biosensors 5, no. 2: 172-186.