OXYGEN SENSOR USING PRINCIPLE OF SURFACE PLASMON RESONANCE AND OXYGEN TRANSMISSION RATE MEASUREMENT SYSTEM INCLUDING THE SAME

• US 20100045997A1
• Filed: 08/18/2009
• Published: 02/25/2010
• Est. Priority Date: 08/21/2008
• Status: Active Grant

• Current Assignee: Korea Advanced Institute of Science and Technology
• Original Assignee: Korea Advanced Institute of Science and Technology
• Inventors: CHOI, Hee Dok, HONG, Jae Min, KIM, Il Doo
• Granted Patent: US 8,237,930 B2
• Time in Patent Office: Days
• US Class Current: 356/445
• CPC Class Codes: G01N 21/554 detecting the surface plasmon resonance of nanostructured metals, e.g. localised surface plasmon resonance

Abstract

An oxygen sensor using the principle of surface plasmon resonance, capable of measuring an oxygen concentration in a measurement chamber by detecting a change in resonance angle or refractive index using field enhancement effects, is provided. An oxygen transmission rate measurement system including the oxygen sensor is also provided. In this invention, only a change in voltage is measured at a fixed angle, thus achieving rapid measurement, and also, a single wavelength light source is used, thus reducing the size of the oxygen sensor and oxygen transmission rate measurement system. The oxygen sensor includes a laser diode for emitting light, a polarizer for converting the emitted light into polarized light, a prism for receiving the polarized light from the polarizer and having a sensor substrate provided on one surface thereof so that the polarized light is reflected, an oxygen concentration measurement chamber provided to enclose the sensor substrate so that oxygen a concentration of which is to be measured is contained therein, a photodiode for measuring the amount of light reflected from the prism, and a microcontroller unit for controlling operation of the oxygen sensor and calculating the oxygen concentration.

Claims

1. An oxygen sensor using a principle of surface plasmon resonance, comprising:

a laser diode for emitting light;

a polarizer for converting light emitted from the laser diode into polarized light;

a prism for receiving the polarized light from the polarizer and having a sensor substrate provided on one surface thereof so that the polarized light is reflected, the sensor substrate being coated with an oxygen-sensitive organic material;

an oxygen concentration measurement chamber provided to enclose the sensor substrate so that oxygen a concentration of which is to be measured is contained therein;

a photodiode for measuring an amount of light reflected from the prism; and

a microcontroller unit for controlling operation of the oxygen sensor and calculating the concentration of oxygen,

wherein the concentration of oxygen is determined using the microcontroller unit having values of absolute concentration corresponding to the amount of light measured using the photodiode, and

the concentration of oxygen is measured in a state in which an incidence angle of the polarized light incident on the sensor substrate is fixed.

2. The oxygen sensor as set forth in claim 1, further comprising:

a pressure measurement pipe, one side of which is connected to the oxygen concentration measurement chamber and the other side of which is connected to a vacuum pump and which includes a pressure gauge provided on an upper surface thereof and a vacuum pump valve disposed between the pressure gauge and the vacuum pump; and

a gas input pipe, one side of which is connected to the oxygen concentration measurement chamber and the other side of which is connected to a gas input valve.

3. The oxygen sensor as set forth in claim 1, wherein the sensor substrate comprises:

a dielectric substrate;

a nano-metal layer including metal nanoparticles applied on the dielectric substrate; and

an organic material layer formed by linking the organic material to the metal nanoparticles of the nano-metal layer.

4. The oxygen sensor as set forth in claim 1, wherein the sensor substrate comprises:

a dielectric substrate;

a nano-metal layer including a metal film applied on the dielectric substrate; and

an organic material layer formed on the nano-metal layer.

5. The oxygen sensor as set forth in claim 3, wherein the organic material is responsible for either or both of adsorption and desorption of oxygen gas.

6. The oxygen sensor as set forth in claim 3, wherein the organic material comprises a metal-porphyrin or hemoglobin which is selectively sensitive to only oxygen.

7. The oxygen sensor as set forth in claim 3, wherein the metal nanoparticles have a diameter ranging from 1 nm to 99 nm.

8. The oxygen sensor as set forth in claim 4, wherein the metal film has a thickness ranging from 1 nm to 99 nm.

9. The oxygen sensor as set forth in claim 3, wherein the dielectric substrate comprises glass.

10. The oxygen sensor as set forth in claim 4, wherein the metal film comprises a metal or a metal-added inorganic or organic material.

23. The oxygen sensor as set forth in claim 1, further comprising a measurement chamber guide disposed to enclose the oxygen concentration measurement chamber.

24. The oxygen sensor as set forth in claim 4, wherein the organic material is responsible for either or both of adsorption and desorption of oxygen gas.

25. The oxygen sensor as set forth in claim 4, wherein the organic material comprises a metal-porphyrin or hemoglobin which is selectively sensitive to only oxygen.

26. The oxygen sensor as set forth in claim 4, wherein the dielectric substrate comprises glass.

11. An oxygen transmission rate measurement system comprising an oxygen sensor using a principle of surface plasmon resonance, the oxygen transmission rate measurement system comprising:

the oxygen sensor, including;

a laser diode for emitting light,

a polarizer for converting light emitted from the laser diode into polarized light,

a prism for receiving the polarized light from the polarizer and having a sensor substrate provided on one surface thereof so that the polarized light is reflected, the sensor substrate being coated with an oxygen-sensitive organic material,

an oxygen concentration measurement chamber provided to enclose the sensor substrate so that oxygen a concentration of which is to be measured is contained therein,

a photodiode for measuring an amount of light reflected from the prism, and

a microcontroller unit for controlling operation of the oxygen sensor and calculating an oxygen concentration change and an oxygen transmission rate; and

an oxygen supplier connected to one side of the oxygen sensor to supply oxygen gas,

wherein the oxygen transmission rate is measured by determining the oxygen concentration change from the amount of the light measured using the photodiode at predetermined temporal intervals.

12. The oxygen transmission rate measurement system as set forth in claim 11, wherein the oxygen supplier comprises:

a gas input pipe one side of which is connected to the oxygen concentration measurement chamber and the other side of which is connected to a gas input valve;

a sample mounting device one side of which is connected to the gas input valve and the other side of which is connected to an oxygen supply valve; and

an oxygen gas supplier one side of which is connected to the oxygen supply valve.

13. The oxygen transmission rate measurement system as set forth in claim 11, wherein the sensor substrate comprises:

a dielectric substrate;

a nano-metal layer including metal nanoparticles applied on the dielectric substrate; and

an organic material layer formed by linking the organic material to the metal nanoparticles of the nano-metal layer.

14. The oxygen transmission rate measurement system as set forth in claim 11, wherein the sensor substrate comprises:

a dielectric substrate;

a nano-metal layer including a metal film applied on the dielectric substrate; and

an organic material layer formed on the nano-metal layer.

15. The oxygen transmission rate measurement system as set forth in claim 11, wherein the organic material is responsible for either or both of adsorption and desorption of oxygen gas.

16. The oxygen transmission rate measurement system as set forth in claim 11, wherein the organic material comprises a metal-porphyrin or hemoglobin which is selectively sensitive to only oxygen.

17. The oxygen transmission rate measurement system as set forth in claim 13, wherein the metal nanoparticles have a diameter ranging from 1 nm to 99 nm.

18. The oxygen transmission rate measurement system as set forth in claim 14, wherein the metal film has a thickness ranging from 1 nm to 99 nm.

19. The oxygen transmission rate measurement system as set forth in claim 13, wherein the dielectric substrate comprises glass.

20. The oxygen transmission rate measurement system as set forth in claim 14, wherein the dielectric substrate comprises glass.

21. The oxygen transmission rate measurement system as set forth in claim 14, wherein the metal film comprises a metal or a metal-added inorganic or organic material.

22. The oxygen transmission rate measurement system as set forth in claim 12, wherein the sample mounting device comprises:

an oxygen sensor connection pipe one side of which is connected to the gas input valve;

a second transmission rate measurement block through which the oxygen sensor connection pipe penetrates and having a recess formed in one side thereof;

a porous metal layer both side surfaces of which are in contact with the recess of the second transmission rate measurement block;

a transmission rate measurement sample a lower surface of which is in contact with the porous metal layer and the second transmission rate measurement block;

a first transmission rate measurement block disposed symmetrically to the second transmission rate measurement block;

a circular O-ring disposed at both sides between the first transmission rate measurement block and the second transmission rate measurement block to support the first transmission rate measurement block and the second transmission rate measurement block; and

a gas supply pipe having a cylindrical shape, which perforates through the first transmission rate measurement block and is connected to a center of an upper surface of the first transmission rate measurement block.

27. The oxygen transmission rate measurement system as set forth in claim 12, wherein the sensor substrate comprises:

a dielectric substrate;

a nano-metal layer including metal nanoparticles applied on the dielectric substrate; and

an organic material layer formed by linking the organic material to the metal nanoparticles of the nano-metal layer.

28. The oxygen transmission rate measurement system as set forth in claim 12, wherein the sensor substrate comprises:

a dielectric substrate;

a nano-metal layer including a metal film applied on the dielectric substrate; and

an organic material layer formed on the nano-metal layer.

29. The oxygen transmission rate measurement system as set forth in claim 12, wherein the organic material is responsible for either or both of adsorption and desorption of oxygen gas.

30. The oxygen transmission rate measurement system as set forth in claim 12, wherein the organic material comprises a metal-porphyrin or hemoglobin which is selectively sensitive to only oxygen.

31. The oxygen transmission rate measurement system as set forth in claim 27, wherein the metal nanoparticles have a diameter ranging from 1 nm to 99 nm.

32. The oxygen transmission rate measurement system as set forth in claim 28, wherein the metal film has a thickness ranging from 1 nm to 99 nm.

33. The oxygen transmission rate measurement system as set forth in claim 27, wherein the dielectric substrate comprises glass.

34. The oxygen transmission rate measurement system as set forth in claim 28, wherein the dielectric substrate comprises glass.

35. The oxygen transmission rate measurement system as set forth in claim 28, wherein the metal film comprises a metal or a metal-added inorganic or organic material.