JP3308289B2 - Urine protein detection method and test strip - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and a test strip for detecting protein in urine, and more particularly to a method for detecting protein in urine based on the protein error method, which reduces false positive reactions in high-density urine. An object of the present invention is to provide a method capable of detecting with high accuracy and a test piece used in the method.

[0002]

2. Description of the Related Art As a method for detecting protein in urine, a sulfosalicylic acid method, a boiling method, and the like have been used for a long time.
It is not suitable for processing a large number of samples due to its operability, sensitivity, and specificity, and measures the color change due to binding to proteins using a recently developed dye such as CBB-G250 or Pyrogallol Red. Although there is a method of quantifying urinary protein by doing, there is a need for a spectrophotometer.
Not suitable for semi-quantitative analysis.

[0003] In recent years, as a qualitative and semi-quantitative method for urinary protein, a test paper method using a protein error method has been mainstream since its development in 1957 in terms of operability and sensitivity. As a test paper method using this protein error method, Japanese Patent Publication No. 39-1
No. 9858, a method of treating a dye using a halogenated hydrocarbon (Japanese Patent Publication No. 43-7991), a method of treating a dye by incorporating an inorganic sulfate in an organic solvent (Japanese Patent Publication No.
-1873), a method of dissolving a dye in ethyl and methyl esters of lower fatty acids (Japanese Patent Publication No. 48-11077), an automatic urine protein quantitative measurement device (Japanese Patent Application Laid-Open No. 50-115594), octahalogen Method for producing phenolsulfophthalein and diagnostic agent for detecting protein containing the same (Japanese Patent Application Laid-Open No. 52-788)
No. 66), a test composition, a test device, a test method and a method for producing a test device (JP-A-52-125397), a protein analysis reagent and a protein analysis method (JP-A-53-15490), An improved method for protein quantification (JP-A-54-73095) and the like have been developed.

[0004]

However, it has long been known that the test paper method using the protein error method increases the reactivity with urine having a high specific gravity. In this regard, there is only a description in Japanese Patent Publication No. 45-1873 that the coagulative positive reaction can be reduced in urine containing high creatinine by using an inorganic sulfate.

It is said that urine used for diagnosis is most suitable in the early morning. However, the first urine in the early morning generally shows a high specific gravity of 1.025 or more.

[0006] A urine protein test strip based on the conventional protein error method shows no trace even if the specific gravity of urine is high, even if the protein is negative.
Positive results in a false-positive reaction showing a false-positive color as if the protein were present. Therefore, in order to measure urine in the early morning using a conventional urine protein test specimen, the semi-quantitative value must be raised by one rank, and accurate determination cannot be made.

The present invention is directed to a method for detecting a protein in urine which improves such disadvantages, reduces false-positive reactions even when urine having a high specific gravity is used, and enables highly accurate, rapid and accurate determination. This is to provide a test piece for use in the test.

[0008]

Means for Solving the Problems In the first invention, when detecting protein in urine based on the protein error method, potassium salt (provided that the difference in reactivity due to the specific gravity of urine is included in the reagent composition) , A potassium salt ( excluding potassium tungstate) in the reagent composition for urine protein detection used in the first invention . Tungstic acid
(Excluding potassium) is impregnated with a reagent composition containing a reagent composition containing urine protein.

The potassium salt used in the present invention includes potassium chloride, potassium sulfate, potassium iodide, phosphoric acid 2
Various inorganic such as potassium or potassium citrate, organic potassium salt may be used (except that the potassium tungstate
Excluded) . Further, the reagent impregnated in the urine protein detection test strip is a conventionally used reagent, for example, citric acid,
It is made of sodium citrate, tetrabromophenol blue, or the like, and is appropriately impregnated with filter paper or the like and dried.

Next, the method of the present invention will be described.
To a predetermined amount of citric acid and sodium citrate, add potassium salt
A solution to which water (excluding potassium tungstate) has been added is dissolved in water to prepare a first solution, and a small amount of tetrabromophenol blue is dissolved in acetone to form a second solution. Then, filter paper for chromatography (manufactured by Whatman)
3MM) is immersed in the first liquid, dried, and then the filter paper is immersed in the second liquid, dried, cut into a predetermined size (5 × 5 mm), and affixed to a support (5 × 80 mm) such as plastic. And a test piece.

[0011] Although the mechanism of action of potassium <br/> beam salt except potassium tungstate is not known, In use of the potassium salt, the potassium salt, or may be added alone It may be contained as a salt of another reagent contained in the test piece. For example, potassium citrate can be used instead of sodium citrate. The amount of the potassium salt, 0.05~2.5mol / l as a concentration in the dipping solution,
In particular 0.1~1.5mol / l is good Masui.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The operation and effects of the present invention will be specifically described below with reference to embodiments. Example 1 A first liquid was prepared by dissolving 3.5 g of citric acid, 9.8 g of sodium citrate and 5 g of potassium chloride in 100 ml of water, and a second liquid was prepared by dissolving 0.06 g of tetrabromophenol blue in 100 ml of acetone . .
Next, the Whatman 3MM filter paper is immersed in the first liquid and dried, and then the filter paper is immersed in the second liquid, dried, cut into a predetermined size,
And a test piece was stuck to a support.

Example 2 A test piece was prepared in the same manner as in Example 1 except that the same amount of potassium sulfate was added instead of potassium chloride in the first liquid of Example 1.

Example 3 A test piece was prepared in the same manner as in Example 1 except that the same amount of potassium iodide was added instead of potassium chloride in the first liquid of Example 1.

Example 4 A test piece was prepared in the same manner as in Example 1 except that 10 g of potassium citrate was added instead of sodium citrate in the first liquid of Example 1.

Example 5 A test piece was prepared in the same manner as in Example 1 except that 8.0 g of dipotassium phosphate was added instead of sodium citrate in the first liquid of Example 1.

Comparative Example For comparison, citric acid 3.5 g and sodium citrate 9.8 g
Was dissolved in water to form a first liquid, and 0.06 g of tetrabromophenol blue was dissolved in acetone to form a second liquid.
A test piece was prepared in the same manner as described above.

Table 1 shows the results of measuring the protein concentration in the same urine using the test pieces of Examples 1 to 5 and Comparative Example.
Shown in In the table, the value of the protein concentration mg / dl is the reflectance photometry 620 nm.
It is a protein concentration determined from a calibration curve in which the K / S value was determined from the reflectance determined by the Kubeluka-Munk equation.

[0019]

[Table 1]

As is clear from the results shown in Table 1, Example 1
-In Example 5 and Comparative Example, there is almost no difference in urine having a low specific gravity of 1.012 or less, but as the specific gravity becomes higher than 1.018, a high concentration value due to a false positive reaction appears in Comparative Examples and a high specific gravity The higher the value, the higher the value. On the other hand, in all of the examples of the present invention, it was recognized that almost the same concentration values were obtained, indicating that the present invention can greatly reduce false positive reactions in urine having a high specific gravity.

[0021]

As described above, the first aspect of the present invention relates to a reagent composition of a test strip for detecting a protein in urine based on the protein error method.
By adding and mixing the potassium salt, it is possible to greatly reduce false positive reactions in urine of high specific gravity as well as urine of low specific gravity, and rank the semi-quantitative value for urine of high specific gravity as in the past. The protein in urine having a low specific gravity to a high specific gravity can be determined with high accuracy and accuracy without changing the specific gravity.

The second invention corresponds to the first invention,
By impregnating a test strip with a reagent composition containing a potassium salt in a test strip for detecting protein in urine, protein in urine can be detected simply, quickly and with high accuracy.

Claims (2)

(57) [Claims] In detecting urinary protein based on the protein error method, potassium salt (but not tungsten) is used as a means for reducing the difference in reactivity due to the specific gravity of urine.
(Excluding potassium acid) . 2. The test strip for detecting protein in urine used in claim 1, wherein the test strip contains a potassium salt in a reagent composition.
A test strip for detecting protein in urine, which is impregnated with a reagent composition containing (but not including potassium tungstate) .