A system and method for resolving and/or mechanically manipulating molecular bonds. A method for resolving molecular bonds includes applying ultrasound to molecules to be manipulated. A magnetic signal associated with the molecules is measured. Whether ultrasound causes dissolution of the bonds of the molecules is determined based on measurements of the magnetic signal.

The invention relates to an examination apparatus (100), a method and a computer program for tracking permanently magnetic beads (107) that are transported by a fluid flowing through a channel (106) of an object (105). The examination apparatus (100) comprises at least three magnetic field sensors (101, 102, 103) and an evaluation unit (104). With the magnetic field sensors, the magnetic field caused by the permanently magnetic beads (107) is detected. Due to shear forces acting in the fluid, the permanently magnetic beads (107) are rotating and the magnetic field caused by the beads (107) is temporally varying. This temporal variation of the magnetic field is used by the evaluation unit (104) for discriminating sub-signals related to single beads (107) from the overall signal generated by the magnetic field sensors. Furthermore, the evaluation unit determines positioning information of individual beads on the basis of the discriminated sub-signals.

A sensor includes: a substrate; a first magnetoresistance element and a second magnetoresistance element, each of which is a magnetoresistance element whose resistance value measured changes depending on a direction of an input magnetic field; and a soft magnetic thin film disposed adjacent to the first and second magnetoresistance elements wherein one of the first and second magnetoresistance elements is positioned on one of end sides of the soft magnetic thin film and other of the first and second magnetoresistance elements is positioned on other of the end sides of the soft magnetic thin film in a plan view in a direction perpendicular to a film surface of the soft magnetic thin film.

Tunnel magneto-resistive (TMR) sensors employing TMR devices with different magnetic field sensitivities for increased detection sensitivity are disclosed. For example, a TMR sensor may be used as a biosensor to detect the presence of biological materials. In aspects disclosed herein, free layers of at least two TMR devices in a TMR sensor are fabricated to exhibit different magnetic properties from each other (e.g., MR ratio, magnetic anisotropy, coercivity) so that each TMR device will exhibit a different change in resistance to a given magnetic stray field for increased magnetic field detection sensitivity. For example, the TMR devices may be fabricated to exhibit different magnetic properties such that one TMR device exhibits a greater change in resistance in the presence of a smaller magnetic stray field, and another TMR device exhibits a greater change in resistance in the presence of a larger magnetic stray field.

A system and method for locating magnetic material. In one embodiment the system includes a magnetic probe; a power module in electrical communication with the magnetic probe to supply current to the magnetic probe; a sense module in electrical communication with the magnetic probe to receive signals from the magnetic probe; and a computer in electrical communication with the power module and the sense module. The computer generates a waveform that controls the supply of current from the power module and receives a signal from the sense module that indicates the presence of magnetic material. The magnetic probe is constructed from a material having a coefficient of thermal expansion of substantially 10.sup.?6/? C. or less and a Young's modulus of substantially 50 GPa or greater. In one embodiment magnetic nanoparticles are injected into a breast and the lymph nodes collecting the particles are detected with the probe and deemed sentinel nodes.

Magneto-impedance (MI) sensors employing current confinement and exchange bias layer(s) for increased MI sensitivity are disclosed. MI sensors may be used as biosensors to detect biological materials. The sensing by the MI devices is based on a giant magneto-impedance (GMI) effect, which is very sensitive to a magnetic field. The GMI effect is a change in impedance of a magnetic material resulting from a change in skin depth of the magnetic material as a function of an external direct current (DC) magnetic field applied to the magnetic material and an alternating current (AC) current flowing through the magnetic material (or adjacent conductive materials). Thus, this change in impedance resulting from a magnetic stray field generated by magnetic nanoparticles can be detected in lower concentrations and measured to determine the amount of magnetic nanoparticles present, and thus the target analyte of interest.

Correlated double sampling (CDS) for magnetoresistive (MR) sensors is provided. Here the MR sensor output is sampled at two closely spaced times. The first sample is MR signal+baseline+noise and is sampled when the modulated magnetic field is non-zero. The second sample is baseline+noise only because it is sampled when the modulated magnetic field is zero. The difference between the first and second samples will have significantly reduced low frequency noise and baseline cancellation. Modulation of the electrical bias provided to the MR sensor can be used to provide a baseline signal for temperature compensation. In a second aspect, we provide MR sensor arrays having input and output multiplexing and demultiplexing for row and column line selection, in combination with a per-sensor switch to prevent noise accumulation and bandwidth reduction from idle MR sensors.

The inventive concepts presented herein relate to methods of identifying molecules identification of molecules using apparatuses including: electromagnetic write-head(s); magneto-resistive read sensor(s), and processor(s). An exemplary method includes magnetically exciting a molecule to be identified using an alternating magnetic field generated by an electromagnetic write-head, measuring a resonant response of the molecule to be identified using a magneto-resistive read sensor; and comparing, using a processor, the resonant response of the molecule to be identified with a table of known resonant responses to identify a chemical composition of the molecule to be identified. The molecule to be identified may optionally be disposed on a biosample substrate which comprises, or is coupled to, a plurality of servo-alignment marks; and the plurality of servo-alignment marks are configured to facilitate alignment of the electromagnetic write-head with the biosample tracks of the biosample substrate.

A biomagnetism measuring device includes a magnetic sensor and a support unit. The magnetic sensor includes a tunnel magneto-resistive element including a fixed magnetic layer, a free magnetic layer and an insulating layer. The insulating layer is disposed between the fixed magnetic layer and the free magnetic layer, and has resistance being changed by a tunnel effect depending on an angle difference between a direction of magnetization of the fixed magnetic layer and a direction of magnetization of the free magnetic layer. The support unit supports the magnetic sensor in such a way that the tunnel magneto-resistive element faces a living body. The magnetic sensor outputs an output signal in accordance with a resistance value of the insulating layer, the resistance value being changed by magnetism emitted from the living body.

A magnetic particle imaging apparatus includes magnets [106,107] that produce a gradient magnetic field having a field free region (FFR), excitation field electromagnets [102,114] that produce a radiofrequency magnetic field within the field free region, high-Q receiving coils [112] that detect a response of magnetic particles in the field free region to the excitation field. Field translation electromagnets create a homogeneous magnetic field displacing the field-free region through the field of view (FOV) allowing the imaging region to be scaled to optimize scan time, scanning power, amplifier heating, SAR, dB/dt, and/or slew rate. Efficient multi-resolution scanning techniques are also provided. Intermodulated low and radio-frequency excitation signals are processed to produce an image of a distribution of the magnetic nanoparticles within the imaging region. A single composite image is computed using deconvolution of multiple signals at different harmonics.