Patent ID: 8779763

Claim:
A magnetic nanoparticle presence detecting sensor, comprising: a support; a sensor body arranged on the support and including a planar ferromagnetic nanostructure having a detection area shaped as a strip bent to form a corner, the sensor body being structured to apply a magnetic field to cause the detection area to selectively assume, in response to the applied magnetic field: a first spin configuration comprising a transverse head-to-head domain wall (TW), and a second spin configuration, wherein a domain wall is absent, the transition from the first spin configuration to the second spin configuration being provided for the applied magnetic field, having a component which is parallel to one of an angled side of the detection area with an intensity greater than a predictable transition threshold, the transition threshold being magneto-resistively detectable and affected by a proximity of a magnetic nanoparticle to the detection area, a plurality of non-magnetic contacts arranged on the support and electrically conductively connected to the sensor body; and a measuring device which measures a magnetoresistance, the device arranged on the sensor and connected to the plurality of non-magnetic contacts, the measuring device being structured to provide a measure of the transition threshold by way of measures of the magneto-resistance of the detection area in the first spin configuration and the second spin configuration assumed upon application of the magnetic field.