Method for Measuring Glucose Concentration in Blood Using Infrared Spectroscopy and Instrument Employing It

• US 20090004682A1
• Filed: 07/26/2005
• Published: 01/01/2009
• Est. Priority Date: 07/30/2004
• Status: Active Grant

• Current Assignee: National University Corporation Chiba University, National University Corporation (University of Fukui)
• Original Assignee: National University Corporation Chiba University
• Inventors: Nomura, Fumio, Kitamura, Akihide, Karatsu, Takashi
• Granted Patent: US 7,974,669 B2
• Time in Patent Office: Days
• US Class Current: 435/14
• CPC Class Codes: G01N 21/3577 for analysing liquids, e.g. polluted water

Abstract

The objective of the present invention is to provide a method and instrument for measuring glucose concentration in blood using infrared spectroscopy. Glucose concentration in blood is measured based on an integrated value obtained by measuring an absorption spectrum that includes the wavelength range of 1020-1040 cm⁻¹, and by integrating the intensity of absorption of the wavelength range of 1020-1040 cm⁻¹ within the absorption spectrum. Alternatively, a glucose concentration in blood is measured based on an integrated value through measuring an absorption spectrum including the wavelength range of 1010-1050 cm⁻¹; obtaining a second-derivative spectrum by calculating a second derivative of the absorption spectrum that includes the wavelength range of 1010-1050 cm⁻¹ in the absorption spectrum; determining an integration range based on the second derivative spectrum; and then obtaining the integrated value by integrating the intensity of absorption based on this determined integration range.

Claims

1. A method for measuring a glucose concentration in blood, comprising the steps of.

measuring an absorption spectrum that includes the wavelength range of 1020-1040 cm⁻

1;

obtaining an integrated value by integrating the absorption intensity of the wavelength range of 1020-1040 cm<sup>−

1</sup> in said absorption spectrum; and

determining the glucose concentration in blood based on said integrated value.

2. The method of claim 1, wherein said integrated value is obtained by a two points based method.

3. The method of claim 1, wherein the glucose concentration in blood is determined based on the relationship between pre-obtained integrated values and glucose concentrations, and an integrated value obtained from an absorption spectrum.

4. A method for measuring a glucose concentration in blood, comprising the steps of:

measuring an absorption spectrum that includes the wavelength range of 1010-1050 cm<sup>−

1</sup>;

obtaining a second-derivative spectrum by calculating the second derivative of an absorption spectrum that includes the wavelength range of 1010-1050 cm<sup>−

1</sup> in said absorption spectrum;

determining an integration range based on the second derivative spectrum;

obtaining an integrated value by integrating the absorption intensity in said determined integration range; and

determining the glucose concentration in blood based on said integrated value.

5. The method of claim 4, wherein said integrated value is obtained by a two points based method.

6. The method of claim 4, wherein the glucose concentration in blood is determined based on the relationship between pre-obtained integrated values and glucose concentrations, and an integrated value obtained from an absorption spectrum.

7. The method of claim 4 wherein the glucose concentration in blood is further measured based on the total protein concentration in the blood.

8. The method of claim 4, wherein the glucose concentration in blood is further measured based on the intensity of absorption in the wavelength range of 1450-1750 cm⁻

1.

9. A device for measuring a glucose concentration in blood comprising:

an absorption spectrum measuring means for measuring an absorption spectrum including the wavelength range of 1020-1040 cm<sup>−

1</sup>;

an integration means that outputs an integrated value by integrating the intensity of absorption of the wavelength range of 1020-1040 cm<sup>−

1</sup> in said absorption spectrum that was measured by the absorption spectrum measuring means; and

a concentration determination means to determine the glucose concentration in blood based on the output by said integration means.

10. A device for measuring a glucose concentration in blood comprising:

an absorption spectrum measuring means for measuring an absorption spectrum including the wavelength range of 1010-1050 cm<sup>−

1</sup>;

a second-derivative spectrum calculation means to determine a second-derivative spectrum by calculating the second derivative of the absorption spectrum including the wavelength range of 1010-1050 cm<sup>−

1</sup>;

an integration range calculation means to determine an integration range based on said second derivative spectrum calculated by said second-derivative spectrum calculation means;

an integration means to obtain an integrated value by integrating the intensity of absorption in said absorption spectrum based on the output by said integration range calculation means; and

a concentration determination means to determine the glucose concentration in blood based on the integrated value obtained b), said integration means.