Test kit, test method, dispensing device

Patent metadata

Field	Value
Publication number	US-11788971-B2
Application number	US-201816620697-A
Country	US
Kind code	B2
Filing date	Apr 10, 2018
Priority date	Jun 14, 2017
Publication date	Oct 17, 2023
Grant date	Oct 17, 2023

Abstract

An object of the present invention is to provide a technology in which an amount of pigment carried from a pigment solution can be accurately measured at the time of testing a surface state of a dispensing probe on the basis of the amount of carried pigment. In a test method according to the present invention, a surface state of a dispensing probe is evaluated on the basis of an amount of pigment carried from an acidic pigment solution into a solution including no pigment.

First claim

The invention claimed is:

1. A test method for evaluating a surface state of a dispensing probe included in a dispensing device that dispenses a liquid sample, the test method comprising:
a step of dispensing a first test solution in which an acidic pigment is dissolved;
a step of cleaning the dispensing probe;
a step of dispensing a second test solution in which no acidic pigment is dissolved;
a step of acquiring an absorbance of the first test solution on a spectrophotometer;
a step of acquiring an absorbance of the second test solution on the spectrophotometer before the acidic pigment is carried;
a step of acquiring an absorbance of the second test solution on the spectrophotometer after the acidic pigment is carried; and
a step of cleaning a surface of the dispensing probe if a calculated amount of the acidic pigment that is carried into the second test solution exceeds a predetermined threshold amount;
wherein the first test solution has a pH of 2.0 or more and 4.4 or less;
wherein the calculated amount of the acidic pigment that is carried into the second test solution is calculated by subtracting the absorbance of the second test solution before the acidic pigment is carried from the absorbance of the second test solution after the acidic pigment is carried to provide a difference, and dividing the difference by a product, the product calculated by multiplying a second difference by a concentration of the first test solution by a volume of the first test solution, the second difference calculated by subtracting the absorbance of the second test solution before the acidic pigment is carried from the absorbance of the first test solution.

2. The test method according to claim 1 ,
wherein in the step of acquiring an absorbance of the second test solution on the spectrophotometer after the acidic pigment is carried, the absorbance of the second test solution is acquired by using an external spectrophotometer instead of a photometer included in the dispensing device.

3. The test method according to claim 1 ,
wherein in the step of acquiring an absorbance of the second test solution on the spectrophotometer after the acidic pigment is carried, the absorbance of the second test solution is acquired by using a spectrophotometer included in the dispensing device.

4. The test method according to claim 1 , further comprising:
a step of dispensing a third test solution having a pH different from the pH of the first test solution and in which the acidic pigment is dissolved;
a step of cleaning the dispensing probe;
a step of dispensing the second test solution into which the acidic pigment is not dissolved;
a step of acquiring an absorbance of the third test solution on the spectrophotometer;
a step of acquiring an absorbance of the second test solution on the spectrophotometer after the acidic pigment is carried from one of the first test solution and the third test solution; and
a step of cleaning the dispensing probe if (1) the acidic pigment is carried from the third test solution, (2) the third test solution has a higher pH than the pH of the first test solution, and (3) a calculated amount of the acidic pigment that is carried from the first or third test solution into the second test solution is less than a second predetermined threshold amount; and
a step of cleaning the surface of the dispensing probe if (1) the acidic pigment is carried from the third test solution, (2) the third test solution has a higher pH than the pH of the first test solution, and (3) the calculated amount of the acidic pigment that is carried from the first or third test solution into the second test solution exceeds the second predetermined threshold amount; and
wherein the calculated amount of the acidic pigment that is carried from the first or third test solution into the second test solution is calculated by subtracting the absorbance of the second test solution before the acidic pigment is carried from the absorbance of the second test solution after the acidic pigment is carried to provide a difference, and dividing the difference by a second product, the second product calculated by multiplying a third difference by a concentration of the first test solution or the third test solution by a volume of the second test solution, the third difference calculated by subtracting the absorbance of the second test solution before the acidic pigment is carried from the absorbance of the first test solution or the third test solution.

5. The test method according to claim 1 , further comprising:
a step of immersing the dispensing probe in the first test solution and then lifting the dispensing probe from the first test solution without sucking the first test solution so as to make the acidic pigment be attached onto an outer surface of the dispensing probe and at least partially be carried into the second test solution as the calculated amount of the acidic pigment carried into the second test solution;
a step of indicating that the outer surface is clean if the calculated amount of the acidic pigment carried into the second test solution is below a second predetermined threshold amount; and
a step of indicating that the outer surface is not clean if the calculated amount of the acidic pigment carried into the second test solution is above the second predetermined threshold amount.

6. The test method according to claim 1 ,
wherein in the step of dispensing the first test solution, the dispensing probe is allowed to enter the first test solution to a first depth to suck the first test solution,
in the step of dispensing the second test solution, the dispensing probe is allowed to enter the second test solution to the first depth to suck the second test solution,
the test method further comprising:
a step of allowing the dispensing probe to enter the first test solution to a second depth different from the first depth to suck the first test solution;
a step of dispensing the first test solution;
a step of cleaning the dispensing probe;
a step of allowing the dispensing probe to enter the second test solution in which no acidic pigment is dissolved to the second depth to suck the second test solution;
a step of dispensing the second test solution in which no acidic pigment is dissolved;
a step of cleaning a portion of the surface of the dispensing probe corresponding to the first depth if the calculated amount of the acidic pigment that is carried into the second test solution exceeds a second predetermined threshold amount; and
a step of cleaning a second portion of the surface of the dispensing probe corresponding to the second depth if the calculated amount of the acidic pigment that is carried into the second test solution exceeds the fourth second predetermined threshold amount.

7. The test method according to claim 1 ,
wherein the dispensing device comprises a first dispensing probe repeatedly used by being cleaned between uses, and a disposable second dispensing probe,
the test method further comprising a dispensing probe determining step of using the first dispensing probe for a first sample and the second dispensing probe for a second sample different from the first sample if the calculated amount of the acidic pigment that is carried into the second test solution by the first dispensing probe is at or above a second predetermined threshold amount, and using the second dispensing probe for both of the first sample and the second sample when the calculated amount of the acidic pigment that is carried into the second test solution by the first dispensing probe is below the second predetermined threshold amount.

8. The test method according to claim 1 , further comprising a step of, if the calculated amount of acidic pigment that is carrie

Assignees

• Hitachi High Tech Corp
• Hitachi High Tech Corp

Inventors

• Nojima Akihiro
• Mori Takamichi
• Yamazaki Isao
• Nonaka Kohei

Classifications

• G01N21/82 Primary

  producing a precipitate or turbidity · CPC title

• G01N35/00623

  of instruments · CPC title

• G01N35/1004

  Cleaning sample transfer devices · CPC title

• G01N21/80 Primary

  Indicating pH value · CPC title

• G01N21/94

  Investigating contamination, e.g. dust (G01N21/85 takes precedence) · CPC title