JPH0422868A - Immune analysis system - Google Patents

Abstract

PURPOSE:To facilitate the dealing with the requirements for measurement over a wide range with one kind of analyzing apparatus by providing plural photometric means and adding respectively corresponding enzymes and substrate liquids thereto, then transferring reaction solns. or reaction vessels to the respective photometric means and making photometry. CONSTITUTION:The light emitting photometric sections 13 are disposed around a reaction tank 1 and the light absorbing photometric sections 16 are disposed in the other positions around the reaction tank 1. The labeling enzymes (e.g.: ALP in the case of a light emission method and POD in the case of a light absorption method) and substrate liquids to be dispensed in the cases of making photometry by the light emission method and the light absorption method are previously selected of the kinds meeting the respective methods and are added to the reaction vessels 12 on the same reaction line. The reaction liquids are transferred by means of a transfer arm 14, from the vessels 12 sent up to the position on the reaction line facing the photometric sections 13 to the reaction vessels 18 and are subjected to the photometry in the case of the range of the measurement items requiring pg/ml to ng/ml values. The vessels 12 are passed in the optical path of a light source 15 and the measurement is made by the photometric sections 16 in the case of the range of the measurement items requiring ng/ml to mug/ml values.

Description

Detailed Description of the Invention [Object of the Invention] (Industrial Application Field) The present invention relates to an immunoassay system that measures the amount of antigen in a sample using an enzyme reaction.

(Prior Art) RIA (radioimmunoassay) method using a radioactive element has conventionally been used for quantitative analysis of the amount of a specific antigen in a sample (specimen). However, since the tA method uses radioactive elements, it requires the installation of special equipment and the operation by a qualified operator, and is troublesome in that it requires careful disposal of waste.

For this reason, instead of this RIA method, EIA (enzyme immunoassay) is used to perform analysis using enzyme reaction.
The law is being implemented. And recently this EIA
Among these methods, analytical methods that utilize antibody-immobilized fine particles such as magnetic materials are becoming popular.

Figure 5 explains the principle of such EIA method.
First, magnetic fine particles (
A solution of Magnetic Particle (hereinafter referred to as MP) 1 is prepared, and by dispensing the sample 4 containing the antigen 3 to be measured into this solution, a first antigen-antibody reaction occurs, and part of the antigen 3 becomes the second one. is bound to one antibody 2. The unbound antigen 3' exists in a free state. Therefore, free antigen 3' is removed using a magnet while MPI is adsorbed, thereby performing so-called B/F separation. Next, by dispensing the second antibody (second reagent) 6 labeled with enzyme 5, a second antigen-antibody reaction occurs, and the antigen 3 to be measured is expressed as MPI.
and a part of the enzyme-labeled antibody 6 to form a sandwich. The unbound enzyme-labeled antibody 6' exists in a free state. Therefore, by using a magnet as described above, B
/F separation is performed to remove free enzyme-labeled antibody 6'.

Next, by dispensing the substrate (third reagent) 7 into this, a third reaction, so-called enzyme reaction, occurs and a reaction product 8 is produced. Since enzyme 5 is bound to this antigen 3,
By photometrically measuring the results of the third reaction state using an absorption method or a luminescence method depending on the item, the amount of antigen 3 proportional to the amount of enzyme 5 can be measured. Here, in conventional immunoassay systems, an analyzer equipped with a means compatible with either an absorption method or a luminescence method is used as a photometric means to measure the amount of a target antigen.

Among the photometric methods, the absorption method has a measurement item range of ng/m.
The luminescence method is used for measuring items ranging from pg/ml to ng/ml.

(Problems to be Solved by the Invention) However, in conventional immunoassay systems, two types of photometric methods must be used depending on the object to be measured, so there is a problem in that two types of analyzers must be prepared. For example, the measurement range of the items targeted by a biochemical analyzer is usually about μg/ml to mg/011 (10-6 to 10-3 g/ml), whereas the measurement range of an immunological analyzer is from pg/ml to 11 g. /m1 (10-12 to 1
0-6g/ [III) and measurement range from 103 to 10
It has widened significantly to 6.

- For example, AFP, which is one of the tumor markers, has a concentration ranging from 065 to 1106 n/ml, that is, 1 m
It has a concentration of up to about 1 g/m, and considering this, 106 measurement ranges are required.

Range 106 means measuring a length of 1 m in units of 1 μm, and range 109 means measuring a length of 1 km in units of 1 μm. However, as such a measuring stick does not currently exist, the absorption method and the luminescence method are used as photometric methods, as described above, depending on the target. Measurement range is 103 to 10 at most.
4 (60 to 80 dB in S,.../N ratio) < Leprosy.

However, if you try to measure up to 11 g/ml using an analyzer that can only measure up to 100 g/ml, for example, you can increase the sample amount by 1000 times.
This is impossible because μNX 1ooO = 10 ml, which significantly exceeds common sense for blood collection. Also, if you try to measure down to μg/ml with a device that can measure down to pg or ng/ml, the measurement range will be 106, which means you will have to create a photometry system with an S/N ratio of 120 dB, which is the current level that is capable of measuring 90 to 100 dB at most. This would be difficult to achieve. It is also possible to dilute the sample to 1/1000, but this means making 10 ml of serum into a 10 ml aqueous solution and using 10 .mu.m of the solution, so a dilution error is unavoidable.

Therefore, at present, it is necessary to use two types of analyzers, each equipped with a light absorbing means and a light emitting means.

The present invention has been made in response to the above-mentioned problems.
The purpose of this invention is to provide an immunoassay system that can meet a wide range of measurement requirements with a single type of analyzer.

Components of the Invention (Means for Solving the Problems) In order to achieve the above object, the present invention involves reacting a sample with an antibody-immobilized microparticle solution corresponding to a measurement item, and further adding an enzyme-labeled antibody solution. In an immune system that measures the amount of antigen by sandwiching the antigen to be measured with antibody-immobilized microparticles and enzyme-labeled antibodies and then adding a predetermined substrate solution to cause an enzyme reaction, it is equipped with multiple photometric means, each with its own photometric method. This method is characterized in that after enzymes and substrate solutions corresponding to the means are added on a common reaction line, the reaction solutions or reaction containers are transferred to a plurality of photometric means for photometry.

(Function) One type of analyzer is equipped with two types of photometric means, for example, an absorption method and a luminescence method, and enzymes and substrate solutions are selected and added according to each photometric method on a common reaction line. This allows one type of analyzer to meet a wide range of measurement requirements.

(Example) The present invention will be described in detail below with reference to the drawings.

FIG. 1 is a block diagram showing a first embodiment of the immunoassay system of the present invention, in which 11 is a reaction tank, and along the periphery of this reaction tank 11 are a large number of reaction containers 1 to accommodate samples to be analyzed.
2 are arranged to form a reaction line. Each reaction vessel 12 is controlled by a drive source (not shown) to move intermittently in the direction of the arrow in a constant cycle. The number shown inside each reaction container 12 means a position Nα (position Nα), and an example in which positions Nα from 1 to 75 are set is shown.

A luminescence photometer 13 is arranged around the reaction tank 1, and is configured such that the reaction liquid can be transferred from the reaction container 12, which has been sent to a position on the opposing reaction line, to the reaction container 18 by the transfer arm 14. Further, an absorbance photometer 16 is arranged at other positions around the reaction tank 1, and is configured such that when the reaction vessel 12 crosses the optical path of the light source 15, the absorbance of the reaction liquid is measured by the absorbance photometer 16. has been done.

Next, a method for performing immunoassay according to this example will be explained. Note that this analysis is performed based on the principle shown in FIG.

Antigen 3 to be measured in reaction vessel 1.2 at position Nα1
The antibody-immobilized magnetic fluid (MP) 1 is dispensed into the sample at Nα2.

This causes the first immune reaction (antigen/antibody reaction) to occur. Next, Nα13. 1.4. 15 and 17°18
．． At step 19, MPI is adsorbed and aggregated using a magnet to perform the first B,.../F separation, and free antigen is removed by suction. Nα with a circle around the number is MP
The position where I is adsorbed is shown. During this time, cleaning is performed with Nα16.

Subsequently, the enzyme-labeled antibody 6 is dispensed with Nα20, stirred with Nα21, and a second immunoassay (antigen-antibody reaction) is performed. At this time, the labeled enzyme to be dispensed is changed depending on whether the luminescence photometry section 13 performs photometry using the luminescence method or the absorption photometry section 16 performs photometry using the absorption method. For example, when measuring light by spectrophotometry, the labeled enzyme is P.
When using OD and performing photometry using the luminescence method, use ALP. Also, use antibodies that have specificity corresponding to each measurement item.

Nα35, 36.37 and 40, 41.42 and 45.
At 46.47, the MPI is again attracted and collected using a magnet to perform a second B/F separation, and the free enzyme-labeled antibody is removed by suction. During this time, Nα38.
Washing is performed at 43.48 ml, and stirring is performed at Nα 39,44.49 ml. That is, B/F separation is performed three times.

Next, the enzyme reaction (third reaction) is performed by dispensing the substrate liquid 7 using Nα53. In this case, the substrate solution should be selected according to the absorption method or luminescence method. During this time, stirring is performed using Nα54.

Next, in Nα55, if the measurement item range is pg/ml to ng/ml, the reaction liquid is transferred from the reaction container 12 to the luminescence photometry unit 13 by the transfer arm 1-4 and photometered by the luminescence method. I do. That is, in the luminescence photometry section 13, the amount of antigen is measured by counting the amount of light emitted from the labeled antibody using a photomultiplier (photomultiplier tube) while the reaction solution is shielded from external light. Also, in Nα68, the range of measurement items is n
If a value of g/ml to μg/ml is required, measurement is performed by the absorption photometer 16 by passing the reaction container 12 through the optical path of the light source 15. In other words, MP is attracted from Nα66 with a magnet, and with MP removed from the optical path, Nα6
The amount of antigen is measured by preparing the reaction solution in step 8.

After the reaction, the reaction vessel 12 is cleaned at Nα69 to Nα75 and prepared for reuse.

According to this example, labeled antibodies and substrate solutions suitable for absorption and luminescence methods are selected in advance from the reaction solution and added to the reaction vessels on the same reaction line, and then added to each photometric section. Since the devices are divided and photometry is performed using a photometry method suitable for each measurement item, a single type of analyzer can meet a wide range of measurement requests. i.e. pg, /'m! 〜ng
The luminescence photometry unit 13 can handle the required range of /ml, and the absorption photometry unit 16 can handle the required range of ng, /ml to μg/ml. As a result, instead of having to prepare two types of biochemical analyzers and immunological analyzers as in the past, most of the components of each can be shared and the purpose can be achieved with one type of apparatus. It is possible to reduce the cost of the device. Furthermore, the measurement range has been increased from 103 to 106.
By being able to improve this by a factor of 0.03, the S/N ratio can be improved from the conventional 60 to 80 dB to an apparent 120 to 140 dB. Furthermore, since only one type of device needs to be prepared, the burden on the operator can be reduced.

FIG. 2 shows a second embodiment of the present invention, in which a reaction container vertical transfer elevator 1 is arranged adjacent to the luminescence photometry section 13.
7, and the reaction container 12 that has proceeded to N.alpha. After the photometry is completed, the reaction vessel 12 is returned to the reaction line by the elevator 17.

The other configurations are the same as in FIG. 1. The second embodiment can also provide the same effects as the first embodiment.

FIG. 3 shows a third embodiment of the present invention, in particular, a luminescence photometry unit] 3 and an absorption photometry unit 16 are both arranged around the reaction vessel 11, and a transfer arm 14 is used to move the inside of each reaction vessel 12 at Nα55. Reaction container 1 of the photometry section corresponding to the reaction solution of
8. In this case, in particular, by making the reaction container 18 of the absorption photometry section 16 square as shown in the figure, stable photometry can be performed without causing photometry errors even when the optical path is off center.

The third embodiment can also provide the same effects as the first embodiment.

FIG. 4 shows a fourth embodiment of the present invention, in which the configuration is similar to that of FIG. 3, but the reaction vessels 18 used in each of the photometric sections 13 and 16 are of the disbose type. be. The fourth embodiment also provides the same effects as the first embodiment.

As described above, according to each embodiment of the present invention, it is possible to meet a wide range of measurement requests by simply preparing one type of analyzer.

The following table shows, as an example to which the present invention is applied, the relationship between the normal value level and the photometric method when each item is measured for tumor markers and hormones.

(Margins below) ○ Measurable △ Some concentration ranges cannot be covered [Effects of the invention] As described above, according to the present invention, a plurality of photometric means are provided on a common reaction line, so one type of Analyzers can handle a wide range of measurement requirements.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing a first embodiment of the immunoassay system of the present invention, Fig. 2 is a block diagram showing a second embodiment of the present invention, and Fig. 3 is a block diagram showing a third embodiment of the present invention. FIG. 4 is a configuration diagram showing the fourth embodiment of the present invention, and FIG. 5 is an EIA
It is an explanatory diagram of the principle of law. 12.18... Reaction container, 13... Luminescence photometry section, 1
4... Transfer arm, 15... Light source, 16...
- Absorption photometry section, 17... Reaction container vertical transfer elevator.

Claims (2)

[Claims] (1) React the sample with the antibody-immobilized microparticle solution corresponding to the measurement item, and then add the enzyme-labeled antibody solution to sandwich the antigen to be measured with the antibody-immobilized microparticles and the enzyme-labeled antibody. In an immune system that measures the amount of antigen by adding a substrate solution and causing an enzyme reaction, it is equipped with multiple photometric means, and after adding the enzyme and substrate solution corresponding to each photometric means on a common anti-upper line, An immunoassay system characterized in that a reaction solution or a reaction container is transferred to a photometric means for measurement. (2) The immunoassay system according to claim 1, wherein the plurality of photometric means includes an absorption method and a luminescence method.