Sensor and methods for measuring of concentrations of components in a liquid

• US 20070295061A1
• Filed: 06/08/2007
• Published: 12/27/2007
• Est. Priority Date: 06/08/2006
• Status: Active Grant

• Current Assignee: Technische Universitã¤T Dresden
• Original Assignee: Technische Universitã¤T Dresden
• Inventors: Gerlach, Gerald, Sorber, Jorg, Gunther, Margarita
• Granted Patent: US 7,854,159 B2
• Time in Patent Office: Days
• US Class Current: 73/61.41
• CPC Class Codes: G01N 33/487 of liquid biological material

Abstract

A sensor for measuring the concentration of components in a liquid, exhibiting a base body with a deformation body, and a hollow chamber. The hollow chamber is on the one side deformable through the deformation body and on the other side rigidly closed. The hollow chamber is completely filled with a swellable polymeric network, which network exhibits a volume phase transition at a certain concentration of components in the liquid. The liquid can have contact to the polymeric network through at least one opening in at least one of the rigid delimiting sides of the hollow chamber. A mechano electrical transducer detects the deflection of the deformation body. The sensor exhibits a servo device (8) working on the deformation body (3), wherein the servo device (8) can be controlled through a control member with a comparator unit (9) such that the deflection of the deformation body (3) is compensated, wherein the corresponding control signal for the servo device (8) represents the measurement value for the concentration of components in the liquid (1).

Claims

1. A sensor for measuring the concentration of a component in a liquid, exhibiting a base body with a deformation body, a hollow chamber, wherein the hollow chamber on the one side is deformable through the deformation body and on the other side is rigidly closed, wherein the hollow chamber is completely filled with the swellable polymeric network which exhibits a volume phase transition at a certain concentration of components in the liquid and through at least one opening in at least one of the rigid delimiting sides of the hollow chamber the liquid can have contact with the polymeric network and wherein a mechano electrical transducer detects the deflection of the deformation body,

characterized in that

the sensor exhibits a servo device (8) working on the deformation body (3), wherein the servo device (8) is thus controllable through a control member with a comparator unit (9) such that the deflection of the deformation body (3) is compensated, and in that the corresponding control signal for the servo device (8) is the measurement size for the concentration of components in the liquid (1).

2. The sensor according to claim 1, wherein in the base body (2) is a semiconductor chip (10), wherein the semiconductor chip (10) comprises a hollow chamber (6) and is mounted to a support (11).

3. The sensor according to claim 1, wherein the deformation body (3) is locally thinned out as a bending plate or as a membrane.

5. The sensor according to claim 1, wherein the deformation body (3) supports the movable electrode of a capacitor arrangement, which movable electrode forms the mechano electrical transducer (4).

6. The sensor according to claim 1, wherein the mechano electrical transducer (4) is integrated into the servo device (8).

7. The sensor according to claim 1, wherein the servo device (8) is a piezo electric element.

8. The sensor according to claim 1, wherein the servo device (8) is an electrodynamic element.

9. The sensor according to claim 1, wherein the servo device (8) is formed of a temperatures sensitive polymer network and a heating device.

10. The sensor according to claim 1, wherein the polymeric network (5) is located in the hollow chamber (6) and exhibits also a temperature sensitivity in addition to the desired sensitivity relative to a component in the liquid and assumes itself the function of a servo device.

11. The sensor according to claim 1, wherein the mechano electrical transducer (4) is a measurement device coupled with the servo device (8).

12. The sensor according to claim 1,wherein the polymeric network (5) is applied as a thin layer in the hollow chamber (6) on the deformation body (3).

13. The sensor according to claim 1, wherein the polymeric network (5) is entered as a body in the hollow chamber (6) between the deformation body (3) and the support (11).

14. The sensor according to claim 1, wherein the base body (2) is a semiconductor chip (10), wherein the semiconductor chip (10) comprises a hollow chamber (6) and is mounted on a support (11), wherein the support has at least one feed flow (12a) and at least one discharge flow (12b) and wherein the liquid (1) has a continuous contact to the polymeric network (5) through the support (11).

15. The sensor according to claim 1, wherein the base body (2) is a semiconductor chip (10), wherein the semiconductor chip (10) comprises a hollow chamber (6) and is mounted on the support (11), wherein the support (11) is coupled to an open volume.

4. The sensor according to claim l,wherein the deformation body (3) comprises one or several piezo resistive resistors (13) as mechano electrical transducers (4).

16. A method for measurement of the concentration of components in a liquid with a sensor exhibiting a base body with a deformation body, a hollow chamber, wherein the hollow chamber on the one side is deformable through the deformation body and on the other side is rigidly closed, wherein the hollow chamber is completely filled with a swellable polymeric network, which exhibits at a certain concentration of components in the liquid a volume phase transition and wherein the liquid has contact to the polymeric network through at least one opening in at least one of the rigid limitation sides of the hollow chamber, and wherein a mechano electrical transducer detects the deflection of the deformation body,

wherein

the servo device (8) working on the deformation body (3) is controlled continuously through a control member with a comparator unit (9), wherein the deflection of the deformation body (3) is continuously compensated, and wherein the respective control signal for the servo device (8) is employed as a measurement value for the concentration of components in the liquid (1).

17. A sensor for measuring a concentration of a component in a liquid comprising

a deformation body;

a hollow chamber formed in part by the deformation body, wherein the hollow chamber on a side is deformable through the deformation body and on other sides is rigidly delimited, and wherein the hollow chamber forms part of a base body (2);