Abstract: A device for detecting a magnetic field response or changes in a magnetic response of at least one magnetic particle in a carrier fluid, the detection comprising measuring the magnetic particles characteristic rotation period, and the measurement involving measurement of a Brownian relaxation in the carrier fluid under influence of an external pulsed magnetic field. The device includes means for generating the pulsed magnetic field, at least two substantially identical detection coils connected in gradiometer coupling to detection electronics for measuring the differential induced voltage which is dependent on the frequency dependent susceptibility or the magnetization change.

Abstract: The present invention relates to a coil comprising a winding (45). The winding comprises a multi-axial cable with one shielding layer connected to ground.

Abstract: The present invention relates to method and device for detecting changes of a magnetic response of at least one magnetic particle in a carrier fluid. The method comprises: using a measuring procedure comprising measuring the characteristic rotation time of said magnetic particle, said measuring procedure further involving measuring Brownian relaxation in said carrier fluid under influence of an external pulsed excitation magnetic field, and based on said influence of said external pulsed excitation magnetic field measuring a hydrodynamic volume of a particle or a change in a hydrodynamic volume of the particle change upon modification of an effective volume of the particle or its interaction with said carrier fluid by detecting change of magnetization of the particle with time by monitoring change of an output signal in detection coil.