JPH0552853A - Checking method of dispensing sample - Google Patents

Abstract

PURPOSE:To enable the checking to see whether dispensing is done correctly or not by adding a diluted liquid containing a component which changes in color tone depending on the density of hydrogen ions in a component analysis which is performed by mixing a body liquor sample and a reagent to react. CONSTITUTION:In a component analysis in a sample which is performed by mixing the body liquor sample such as blood and a reagent to react in a reaction container, an acid or alkaline diluted liquid containing a component which changes in color tone depending on the density of hydrogen ions is added to a system to execute the component analysis. The component changing in color tone herein used is a pH indicator having a discoloring area near a neutral level. When a relatively thin acid or alkaline solution is mixed with the body liquor for a buffer capacity of the body liquor, the mixed solution indicates pH near a neutral level. Therefore, with the use of a weak acid or alkaline solution containing a pH indicator having a discoloring area near a neutral level, color tone changes between the states when the diluted solution alone exists and when the body liquor is mixed therein. This change in the color tone enables the judgment of whether the body liquor is dispensed into the container correctly or not.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention allows a sample of a body fluid such as blood to be reacted with a reagent in a reaction container to detect a specific component contained in the sample, and the sample is dispensed into the reaction container. Regarding the method to confirm that.

[0002]

2. Description of the Related Art In infectious disease tests and cross-compatibility tests by agglutination reaction, a body fluid sample such as plasma or serum and a test reagent are dispensed into a reaction container and mixed to react. A biochemical analyzer is used. In this case, if the sample is not dispensed as expected, the measured value becomes abnormally low, resulting in a low value abnormality. For this reason, when retesting is necessary or when the poor dispensing is overlooked, the sample is excluded from the healthy subject group. On the contrary, if the above-mentioned situation occurs in the infectious disease test, which is one of the pre-transfusion tests, the infectious disease-positive person (unhealthy person) is determined to be the infectious disease-negative person (healthy person), and the infectious disease is detected. Will result in the propagation of. Similarly, in the cross-matching test, which is one of the pre-transfusion tests, there is a possibility that it will be judged as compatible even though it is a combination of incompatible blood. Therefore, there has been a strong demand for a method capable of determining whether or not the sample plasma or serum is correctly dispensed into the reaction container.

On the other hand, the method disclosed in Japanese Patent Laid-Open No. 59-17161 is known as one means for confirming the blood group and the dispensing of a specimen at the time of infectious disease examination. However, this conventional technique is a confirmation method in the dilution step which is the pretreatment of the sample. That is, since it is not a method for confirming the dispensing of the sample into the reaction container which is used for actual determination, it cannot fully meet the demand.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object thereof is to react a body fluid sample such as blood with a reagent in a reaction container to obtain a specific component contained in the sample. It is an object of the present invention to provide a method capable of easily confirming whether or not a body fluid sample such as blood has been correctly dispensed into a reaction container when performing the detection.

[0005]

Means and Actions for Solving the Problems A method for confirming the dispensing of a sample according to the present invention is such that when a body fluid sample and a reagent are mixed and reacted in a reaction container and a component in the sample is analyzed, the color tone depends on the hydrogen ion concentration. It is characterized in that an acidic or alkaline diluting solution containing varying components is added to the system for carrying out the component analysis.

As the component used in the method of the present invention, the color tone of which changes depending on the hydrogen ion concentration, a pH indicator having a discoloration range near neutral is used. Although such a pH indicator is not particularly limited, for example, sodium alizarin sulfonate or cresol red can be used.

[0007]

The body fluid has a property of homeostasis of the hydrogen ion concentration (pH), that is, a buffering capacity for keeping the pH at around 7.4. Due to this buffering capacity, when a body fluid is mixed with a relatively dilute acid solution or alkali solution, the mixed solution exhibits a pH in the vicinity of neutrality.

Therefore, according to the present invention, when a dilute weakly acidic or weakly alkaline solution containing a pH indicator having a discoloration range near neutral is used, the body fluid is mixed with the diluted solution only. The color tone changes from time to time. Therefore, from this change in color tone, it is possible to easily determine whether or not the body fluid has been dispensed correctly into the reaction container.

[0009]

【Example】

Example 1 Example using sodium alizarin sulfonate as a pH indicator 1) Method for preparing diluted solution

Sodium chloride (NaCl, MW; 58.44)
) 0.9 g and citric acid (C ₆ H ₈ O ₇ · H ₂ O,
MW; 210.14) 0.21 g and sodium alizarin sulfonate (C ₁₄ H ₇ NaO ₇ S.H ₂ O, MW; 360.
28) 20 mg was completely dissolved in 100 mL of purified water. This solution had a pH of 3.2 and became a yellowish solution. Plasma (500 uL) was added to this solution (1,000 uL) to prepare 3-fold diluted plasma. At this time, the color tone of the diluted solution changed from yellow to magenta when plasma was added. This will be described in more detail below.

Table 1 shows plasma A and plasma B each 500
The change in pH when the above-mentioned diluted solution is added to uL is shown. Table 2 shows 510 nm of alizarin sodium sulfonate used as a pH indicator in the above diluted solution.
It shows the relationship between the absorption rate and pH in. Further, FIG. 1 is a graph of the pH / absorbance data shown in Table 2.

[0012]

[Table 1]

[0013]

[Table 2]

From the above data, even when a 6-fold dilution is carried out using the above-mentioned diluent, the pH only drops to around 6.5, so that the coloration degree of diluted plasma changes from 2-fold to 6-fold.
It was found that there was almost no change until the double dilution. Therefore, it is possible to determine the presence or absence of plasma by observing the degree of reddish purple coloration. 2) Application to cross compatibility test

Donor blood cells (10 uL) and the above diluted solution (100)
0 uL was mixed to prepare a 1% hemocyte suspension. After adding 40 uL of this hemocyte suspension to a well in the microplate, 10 uL of recipient plasma was further added to the well. Then, the inside of the well was sufficiently stirred by an operation such as giving vibration. The plate was left for about 30 minutes to form a hemagglutination image, and then the agglutination image was determined and plasma dispensing was confirmed. Since the solution was colored reddish purple in the well into which plasma was dispensed, the presence or absence of plasma could be easily determined.
It was also confirmed that this diluted solution had no effect on the agglutination reaction in blood group examination. Second Example When cresol red was used as a pH indicator

Sodium chloride (NaCl, MW; 58.44)
) 0.9 g, and trishydroxymethylaminomethane [H ₂ NC (CH ₂ OH) ₃ . MW; 121.14] 0.12
and g were added to 90 mL of purified water. To this, 20 mg of cresol red (C ₂₁ H ₁₈ O ₅ S, MW; 382.44) was dissolved in a small amount of ethanol and added, and further purified water was added to make the total volume 100 mL. This gave a magenta solution with a pH of 8.8.

1,000 μL of the solution obtained above was added to plasma 50
0 uL was added to prepare 3-fold diluted plasma. At this time, the reddish purple color of the diluted solution turned yellow when plasma was added. This will be described in more detail as follows.

Table 3 shows 500 plasma A and 500 B plasma, respectively.
The change in pH when the above-mentioned diluted solution is added to uL is shown. Table 4 shows the relationship between the absorbance at 570 nm of cresol red used as a pH indicator in the above diluted solution and pH. Further, FIG. 2 is a graph of the data in Table 4.

[0019]

[Table 3]

[0020]

[Table 4]

From the above data, even if 6-fold dilution is performed using the above-mentioned diluent, the pH does not reach around 8.0. Therefore, even if plasma is diluted to 6-fold with this diluent, it is diluted. Almost no reddish purple color is observed in the liquid. From the above facts, as in the case of Example 1, even when the diluted solution prepared in this Example is used, it is possible to determine whether or not plasma is contained based on the degree of color change.

[0022]

As described in detail above, according to the present invention,
When reacting a body fluid sample such as blood with a reagent in the reaction container and detecting a specific component contained in the sample, it is easy to determine whether the body fluid sample such as blood has been correctly dispensed into the reaction container. Can be confirmed. In addition, the following specific effects can be obtained.

The ABO blood group test includes a front test for blood cells and a back test for plasma. In the front test, since the test object is blood cells, it can be easily determined whether blood cells have been dispensed when determining the result of the agglutination reaction. However, plasma is the subject of the test A
In the back blood test and the infectious disease test of the BO blood group test, the plasma dispensing could not be confirmed. However, by applying the present invention, it became possible to easily confirm the plasma dispensing. Another advantage is that this method can be applied to both plasma and serum.

[Brief description of drawings]

FIG. 1: pH of Alizarin Red solution and its 570n
The graph which shows the relationship with the light absorbency of m.

FIG. 2: pH of cresol red solution and its 570n
The graph which shows the relationship with the light absorbency of m.

Claims (1)

[Claims] 1. A component analysis of an acidic or alkaline diluting solution containing a component whose color tone changes depending on the concentration of hydrogen ions when the reaction of mixing a body fluid sample and a reagent in a reaction container to analyze the component in the sample. A method for confirming sample dispensing, which comprises adding to a system for carrying out.