Sensor device for target particles in a sample

A sensor device for determining an amount of target particles at a contact surface of a sample chamber in which a sample with said target particles can be provided, comprising:

• a sensor element for detecting the target particles in the sample chamber and for providing at least one sensor signal;
• an evaluation unit for directly or indirectly determining the amount of target particles in a first zone immediately at the contact surface and in a second zone a distance away from the contact surface based on the at least one sensor-signal;
• at least one magnetic field generator for generating at least two magnetic excitation fields of different configuration in the sample chamber, whereby the magnetic field generator comprises at least two conductor wires that can selectively be supplied with excitation currents and that have different geometrical arrangements with respect to the magnetic sensor element;
• and
• a magnetic sensor element for detecting magnetic reaction fields generated by magnetic target particles in reaction to the magnetic excitation fields and for providing the sensor-signals.

A sensor device for determining an amount of target particles at a contact surface of a sample chamber in which a sample with said target particles can be provided, comprising:

• a sensor element for detecting the target particles in the sample chamber and for providing at least one sensor signal;
• an evaluation unit for directly or indirectly determining the amount of target particles in a first zone immediately at the contact surface and in a second zone a distance away from the contact surface based on the at least one sensor-signal;
• and
• pairs of conductor wires that are arranged symmetrically with respect to a magnetic sensor element, wherein the contact surface comprises binding sites to which target particles can bind.

A sensor device for determining an amount of target particles at a contact surface of a sample chamber in which a sample with said target particles can be provided, comprising:

• a sensor element for detecting the target particles in the sample chamber and for providing at least one sensor signal;
• an evaluation unit for directly or indirectly determining the amount of target particles in a first zone immediately at the contact surface and in a second zone a distance away from the contact surface based on the at least one sensor-signal;
• and
• a manipulation comprising a magnetic field generator for actively moving the target particles, wherein the manipulation device is configured to remove free target particles from a sensitive region of the sensor element.

A sensor device for determining an amount of target particles at a contact surface of a sample chamber in which a sample with said target particles can be provided, comprising:

• a sensor element for detecting the target particles in the sample chamber and for providing at least one sensor signal;
• and
• an evaluation unit for directly or indirectly determining the amount of target particles in a first zone immediately at the contact surface and in a second zone a distance away from the contact surface based on the at least one sensor-signal,
• wherein the evaluation unit is configured to perform an evaluation of a temporal course of the sensor signal, the evaluation takes place with respect to stochastic movements of the target particles, and/or wherein the evaluation unit is configured to determine a noise power of the sensor signal after a high-pass filtering, and/or wherein the evaluation unit is configured to determine an average number of the target particles in the second zone and a variance of the average number, and/or wherein the evaluation unit is configured to infer information about an amount of clustered target particles, about a coverage of the contact surface, and/or about diffusion characteristics of the target particles.

A method for determining an amount of target particles at a contact surface adjacent to a sample chamber in which a sample with said target particles is provided, comprising the acts of:

• detecting the target particles in the sample chamber;
• providing at least one sensor signal with a sensor element;
• directly or indirectly determining with an evaluation unit the amount of target particles in a first zone immediately at the contact surface and a second zone a distance away from the contact surface based on the at least one sensor signal;
• and
• providing at least two sensor signals that are in a different way sensitive to the amount of target particles in the first zone and the second zone, respectively,
• wherein the contact surface comprises binding sites for specifically binding the target particles,
• wherein a first sensor signal of the at least two sensor signals is measured with a sensitivity which is higher in the first zone than in the second zone, and a second sensor signal of the at least two sensor signals is measured with a sensitivity which is lower in the first zone than in the second zone.

A method for determining an amount of target particles at a contact surface adjacent to a sample chamber in which a sample with said target particles is provided, comprising the acts of:

• detecting the target particles in the sample chamber;
• providing at least one sensor signal with a sensor element;
• directly or indirectly determining with an evaluation unit the amount of target particles in a first zone immediately at the contact surface and a second zone a distance away from the contact surface based on the at least one sensor signal;
• and
• deriving the at least one sensor signal from magnetic reaction fields of magnetic target particles that were excited with magnetic excitation fields of different configurations.

A method for determining an amount of target particles at a contact surface adjacent to a sample chamber in which a sample with said target particles is provided, comprising the acts of:

• detecting the target particles in the sample chamber;
• providing at least one sensor signal with a sensor element;
• directly or indirectly determining with an evaluation unit the amount of target particles in a first zone immediately at the contact surface and a second zone a distance away from the contact surface based on the at least one sensor signal;
• and
• evaluating a temporal course of the sensor signal with respect to stochastic movements of the target particles.