JPH11271222A - Urine examination method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make highly precise examination of urine by measuring the quantity of glucose in the urine without using reagent and test paper. SOLUTION: At least one of a piece of light having a wavelength in a range of 1600-1680 nm and another piece of light having a wavelength in a range of 2100-2300 nm is radiated to urine and differential operation is performed for an absorption spectrum obtained from the light transmitted through the urine to measure the quantity of glucose in the urine. In this case, an optical path length at the time when the light having a wavelength in a range of 1600-1680 nm is used for measurement is made longer than another optical path length at the time when the light having a wavelength in a range of 2100-2300 nm is used for measurement.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a urine test method for testing urine components by an optical method such as an absorption spectrophotometer without using a reagent or test paper.

[0002]

2. Description of the Related Art An optical urine test method is disclosed in
As described in JP-A-3-94158 and JP-A-2-27262, a method of optically measuring the color reaction between a reagent applied on a test paper and test urine is generally used.
However, the above-mentioned method has a problem that consumables such as reagents and test papers are required, and there is a problem that a potential error easily occurs because the method is an indirect method through a mediation reaction. A method for performing a urine test without using paper or the like is desired.

As a urine test method without using reagents or test papers, a method utilizing the principle of a saccharimeter described in JP-A-9-145605 or a method disclosed in JP-A-9-171015 is disclosed. A method using Raman spectroscopy as described in a gazette is known.

[0004]

However, since the method utilizing a color reaction by a reagent mainly employs a colorimetric method based on reflected light measurement, it was not necessary to consider the optical path length of the measurement sample. The test method using a glucose meter uses visible light, so it is not easily affected by transparent water.However, urine is directly determined using near-infrared light as in the method using Raman spectroscopy. In this method, the absorption of water, which is the main component of urine, greatly affects the test. In particular, 1400nm
Water absorption near and around 1900 nm has large absorption, and accurate measurement results cannot be obtained unless measurement is performed in consideration of the optical path length in urine.

[0005] Incidentally, it has been found that the amount of glucose in urine is highly useful as a urine test item, and that the light absorption characteristics near the wavelengths of 1600 to 1680 nm and 2100 to 2300 nm have a great correlation with the glucose concentration.

[0006] Therefore, the present invention focuses on the above-mentioned problems, and makes it possible to measure the amount of glucose in urine without using a reagent, test paper, or the like, and to perform a urine test with high accuracy. It is an object.

[0007]

In order to achieve the above object, according to the first aspect of the present invention, at least one of light having a wavelength in the range of 1600 to 1680 nm and light having a wavelength in the range of 2100 to 2300 nm is used. Urine was irradiated, and the amount of glucose in the urine was measured from light transmitted through the urine. Further, in the invention according to claim 2, in the invention according to claim 1,
A method for measuring the amount of glucose in urine by performing a differential operation process on an absorption spectrum obtained from light transmitted through urine, wherein the invention according to claim 3 is the method according to claim 1 or 2, When measuring the amount of glucose in urine using light having a wavelength in the region of 1600 to 1680 nm, the urine is measured more than when measuring the amount of glucose in urine using light having a wavelength in the region of 2100 to 2300 nm. The length of the light path inside was made longer.

[0008]

According to the first aspect of the present invention, light having a wavelength in the range of 1600 to 1680 nm, which has a large correlation with the glucose concentration, is used.
The urine is irradiated with at least one of light having a wavelength in the range of 00 to 2300 nm, and the amount of glucose in the urine is measured from the light transmitted through the urine. Urine tests can be performed by volume.

According to the second aspect of the present invention, since the amount of glucose in urine is measured using a differential calculation process effective for quantifying the amount of components in urine, the amount of glucose in urine can be measured accurately. In addition, measurement accuracy can be improved.

According to the third aspect of the present invention, when the amount of glucose in urine is measured using light having a wavelength in the range of 1600 to 1680 nm, urine is measured using light having a wavelength in the range of 2100 to 2300 nm. Since the optical path length in urine was longer than when measuring the amount of glucose in, it was possible to measure the amount of glucose in urine with the optimal optical path length considering the absorbance of water,
Measurement accuracy can be improved.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a urine test method according to an embodiment will be described in detail. FIG. 1 is a block diagram showing a configuration of a urine test apparatus. The urine test apparatus includes an test apparatus control unit 1, a light source unit 2, a spectroscope 3, a wavelength control unit 4, and an optical path length control unit 5.
, A light receiving unit 7, a calculation and measurement unit 8, a memory unit 9, and a display unit 10.

The inspection device control unit 1 includes a light source unit 2, a wavelength control unit 4, an optical path length control unit 5, an operation measurement unit 8, and a memory unit 9.
And the display unit 10 are controlled. The light source unit 2 uses a white light source that can stably output light of sufficient intensity in the near infrared light region. The spectroscope 3 separates the light output from the light source unit 2 and uses a slit or a grating. The wavelength controller 4 is a circuit that controls the wavelength of light output from the spectroscope 3. The light receiving unit 7 is provided in a test container for storing urine 6 and receives light output from the spectroscope 3, and can move in the test container in a direction away from and close to the spectroscope 3. It has become. The optical path length control unit 5 is a circuit that controls the distance between the spectroscope 3 and the light receiving unit 7, that is, the optical path length by moving the light receiving unit 7, and the light output from the spectroscope 3 is long. Control is performed so that the optical path length becomes shorter as the wavelength becomes longer. For example, the optical path length is set to 1 cm when measuring the absorbance up to a wavelength of 1400 nm, the optical path length is set to 1 mm when measuring the absorbance near the wavelength of 1600 nm, and the optical path length is set to 1 mm or less when measuring the absorbance near the wavelength of 2200 nm.

The memory unit 9 stores the light intensity in the light receiving unit 7 before the urine 6 enters the test container, that is, when there is air between the spectroscope 3 and the light receiving unit 7. Is stored. Using the reference stored in the memory unit, the calculation and measurement unit 8 obtains a continuous absorption spectrum of a minute section required for the differentiation process, and performs two differential calculation processes on the continuous absorption spectrum to obtain 2
This is a circuit for calculating the second derivative spectrum. The display unit 10
Displays the result measured by the arithmetic and measurement unit 8.

That is, by using this inspection apparatus, the absorbance can be automatically measured at the optimum optical path length according to the measurement wavelength, without the measurer being conscious of the condition of the optical path length.

FIG. 2 is a diagram showing the absorbance characteristics of water in the infrared region. As can be seen from this figure, water has a wavelength of 1200 nm
There is almost no absorption up to the vicinity. Therefore, at a wavelength of 1200 nm or less, it is preferable to increase the optical path length in order to emphasize and measure the absorption by the substance contained in the sample. In the case of a sample that is mostly water, such as urine, there is almost no absorption of water, so that a sufficiently measurable transmitted light can be obtained even with an optical path length of about 1 to 10 cm. In addition, the wavelength around 1400 nm and 19
There is an absorption peak near 00 nm, and the absorbance increases extremely as the wavelength becomes longer from the absorption peak. In other words, in measurement at a wavelength of 1200 nm or more, unless the optical path length of the sample is extremely short, light cannot pass through the sample and measurement becomes impossible, and if it is 1700 nm or more, the optical path length of the sample must be further shortened. Light cannot pass through the sample, making measurement impossible. Therefore, when testing urine at a wavelength of 1200 nm or more, an optical path length of 1 cm or less is preferable.

FIG. 3 is a diagram showing the absorbance characteristics of glucose. From this figure, it can be seen that the wavelength range is 1600 to 1680 nm and the wavelength range is 2100 to 23.
It can be seen that there is an absorption peak of glucose at 00 nm. That is, when performing a urine test, the amount of glucose can be measured by measuring the absorbance in a wavelength range of 1600 to 1680 nm and a wavelength range of 2100 to 2300 nm in which the correlation with glucose is large. Note that, within the above wavelength range, even if measurement is performed at a plurality of wavelengths, measurement may be performed at a single wavelength, and measurement results other than the above wavelength range may be added to the measurement results within the above wavelength range. Is also good. By the way, in order to perform the differentiation process, it is premised that the absorbance is measured continuously and finely in a narrow wavelength range to a certain extent. In actuality, this means the result of absorbance measurement at many wavelengths.

FIG. 4 is a graph showing a second derivative spectrum of the urine absorbance. The line (5 levels, N = 3) shown in the figure is the glucose concentration determined in advance to 5 levels in normal urine. This is the result of the sample created as follows. From this figure, it can be confirmed that a difference appears in the second derivative depending on the glucose concentration. However, the data shown here is for
It is a part of the data of 1680 nm and the wavelength range of 2100 to 2300 nm.

FIG. 5 is a diagram showing the relationship between the amount of urinary glucose estimated from the near-infrared absorbance and the true amount of urinary glucose. From this figure, it can be seen that the estimated value and the true value are almost equal. .

The urine test method of the present embodiment is a rational test method taking these factors into consideration, that is, using the above-described test apparatus, the urine test method has a large correlation with the glucose concentration.
Irradiate urine with light having a wavelength in the range of ~ 1680 nm, measure the amount of glucose in the urine from the light transmitted through the urine, similarly, the correlation with glucose concentration is large 2100
This is a method of irradiating urine with light having a wavelength in the range of 22300 nm and measuring the amount of glucose in urine from the light transmitted through the urine. In other words, since the method combines a measurement wavelength that is optimal for urinalysis, an optical path length that is optimal for the measurement wavelength, and differential processing, direct inspection of urine, which has been difficult in the past, can be easily performed.

Although the preferred embodiment of the present invention has been described in detail with reference to the drawings, the specific configuration is not limited to this preferred embodiment, and a design change or the like may be made without departing from the scope of the present invention. Even if present, it is included in the present invention. For example,
In the embodiment, the optical path length is changed by controlling the distance between the spectroscope and the light receiving unit. However, the optical path length may be adjusted by another means. For example, urine may be put into a test container 11 having a flat L shape as shown in FIG. 6, and the test container 11 may be moved between the spectroscope and the light receiving unit to change the optical path length. Further, instead of the test container 11 of FIG. 6, a flat triangular test container 12 as shown in FIG. 7 may be used.

[0021]

As described above, according to the first aspect of the present invention, the correlation between glucose and glucose concentration is 1600 to 1600.
Urine is irradiated with at least one of light having a wavelength in the region of 1680 nm and light having a wavelength in the region of 2100 to 2300 nm, and the amount of glucose in the urine is measured from the light transmitted through the urine. The urine test can be performed by measuring the amount of glucose in the urine without using any method.

According to the second aspect of the present invention, since the amount of glucose in urine is measured using the differential operation processing, an accurate amount of glucose can be measured, and the measurement accuracy can be improved. The effect is obtained.

According to the third aspect of the present invention, 1600 to 16
When measuring the amount of glucose in urine using light having a wavelength in the region of 80 nm, the amount of urinary glucose is measured more than when measuring the amount of glucose in urine using light having a wavelength in the region of 2100 to 2300 nm. Since the optical path length is increased, the amount of glucose in urine can be measured with an optimal optical path length in consideration of the absorbance of water, and the effect of improving the measurement accuracy can be obtained.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a urine test apparatus.

FIG. 2 is a diagram showing the absorbance characteristics of water in the infrared region.

FIG. 3 is a diagram showing the absorbance characteristics of glucose.

FIG. 4 is a diagram showing a second derivative spectrum of urine absorbance.

FIG. 5 is a graph showing the relationship between the amount of urinary glucose estimated from near-infrared absorbance and the true amount of urinary glucose.

FIG. 6 is a (i) perspective view and (ii) a plan view showing an inspection container.

FIG. 7 is a (i) perspective view and (ii) a plan view showing an inspection container.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Inspection apparatus control part 2 Light source part 3 Spectroscope 4 Wavelength control part 5 Optical path length control part 6 Urine 7 Light receiving part 8 Arithmetic measurement part 9 Memory part 10 Display part 11, 12 Inspection container

Claims (3)

[Claims] A light having a wavelength in the range of 1600 to 1680 nm and 21
A urine test method comprising irradiating urine with at least one of light having a wavelength in the range of 00 to 2300 nm, and measuring the amount of glucose in the urine from the light transmitted through the urine. 2. The urine test method according to claim 1, wherein the amount of glucose in the urine is measured by performing a differential operation on an absorption spectrum obtained from light transmitted through the urine. 3. When measuring the amount of glucose in urine by using light having a wavelength in the range of 1600 to 1680 nm, 2100 to 23
3. The urine test method according to claim 1, wherein an optical path length in the urine is made longer than when measuring an amount of glucose in the urine using light having a wavelength in a region of 00 nm.