The invention relates to the identification of molecules using an apparatus which includes: a head module comprising: an electromagnetic write-head configured to magnetically excite the molecule to be identified with an alternating magnetic field; and a magneto-resistive read sensor for measuring a resonant response of the magnetically excited molecule to be identified. The apparatus also includes a processor coupled to the magneto-resistive sensor, the processor being configured to compare the resonant response to a table of known resonant responses to identify a chemical composition of the molecule to be identified.

Methods and apparatuses for sensing biological functions are disclosed. Sensors can be implanted in an organ, such as the brain, and a magnetic field gradient applied to the biological tissue. The field causes the sensors to have different resonant frequencies allowing their spatial localization. The sensors can harvest power from the external coils to be able to retransmit data.

The present invention relates to systems and methods that utilize a combination of immunoassay and magnetic immunoassay techniques to detect an analyte within an extended range of specified concentrations. In particular, a device includes a housing, a heterogeneous surface capture immunosensor within the housing and configured to generate a first signal indicative of the concentration of the analyte in an upper concentration range, and a homogeneous magnetic bead capture immunosensor within the housing and configured to generate a second signal indicative of the concentration of the analyte in a lower concentration range.

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 present invention provides a method for acquiring an aptamer capable of specifically binding to the low molecular nitrogen-containing organic compound. The method comprises (a) preparing an aqueous solution containing the low molecular nitrogen-containing organic compound and a DNA library; (b) fractionating the aqueous solution by electrophoresis using an electroosmotic-flow-eliminated capillary to provide a fraction containing a composite including the low molecular nitrogen-containing organic compound and a single-stranded DNA contained in the DNA library; and (c) amplifying the single-stranded DNA included in the composite by a PCR method to acquire the amplified gene as the aptamer capable of specifically binding to the low molecular nitrogen-containing organic compound. The present invention provides a method for acquiring an aptamer capable of specifically binding to the low molecular nitrogen-containing organic compound contained in a DNA library by an electrophoresis method.

A method and system for detecting a target molecule. The method includes allowing a fluid containing the target molecule to pass by a complementary moiety attached to a paramagnetic ion so as to cause the complementary moiety and the paramagnetic ion to change a position. A magnetic effect change caused by the change in position of the paramagnetic ion is detected. The target molecule is identified based on the identity of the complementary moiety and the detected magnetic effect change.

The present disclosure is directed towards characterizing liquids through the use of magnetic discs that rotate in response to dynamic magnetic fields. In some embodiments, a light beam is transmitted into the liquid while the magnetic discs rotate, and one or more parameters a light beam signal associated with the transmitted light beam are identified. Various characteristics of the liquid may be detected based on the one or more parameters of the light beam signal.

A magnetic spectrometer is integrated in a semiconductor substrate and provides high sensitivity without using an external magnet field. The spectrometer includes one or more highly stable on-chip oscillator and LC resonator. A current caused to pass through the inductor generates a magnetic field and polarizes the nanoparticles placed in its proximity, thereby changing the effective inductance of the inductor, and in turn, modifying the oscillation frequency of the LC resonator. The shift in the oscillation frequency is used to characterize the nanoparticles and measure their magnetic susceptibility frequency profile. The spectrometer operates at multiple frequencies over a diverse range without using a reference sensor thereby effectively increasing its spatial multiplexing density. The magnetic spectrometer uses the relationship between the sizes of the particles and the resonance frequency F.sub.res and/or the magnetic frequency spectrum of the particles as a spectroscopic means of differentiating between the particles.

Embodiments are directed to a sensor having a first electrode, a second electrode and a detector region electrically coupled between the first electrode region and the second electrode region. The detector region includes a first layer having a topological insulator. The topological insulator includes a conducting path along a surface of the topological insulator, and the detector region further includes a second layer having a first insulating magnetic coupler, wherein a magnetic field applied to the detector region changes a resistance of the conducting path.

A biosensor includes a magnetic structure having grooved surface to biologically bond magnetic labels to a biological substance within the grooves. The grooves are positioned within the magnetic structure so that stray magnetic fields from the magnetic structure magnetize magnetic labels within the groove. The magnetic labels may be magnetic nanoparticles or magnetic microbeads. The techniques may reduce or eliminate the usage of any external magnetic field generator, e.g., electromagnets or current lines.