JPH0422867A - Immune analysis system - Google Patents

Abstract

PURPOSE:To measure the reaction process on the midway to reaction liquids by moving the magnets disposed in the prescribed positions on a circumference in synchronization with the movement of reaction vessels. CONSTITUTION:A driving source 16 moves the respective reaction vessels by one turn plus one pitch per cycle. A driving source 16 moves the respective magnets 13 one turn per cycle in synchronization with the movement of the vessels 12 disposed opposite thereto. The respective magnets 13 eventually return to the home positions and the respective vessels 12 advance to the forward positions by one pitch each in this way. All the vessels 12 pass a photometric section 14 at the time of this on turn plus one pitch movement, by which the measurement of all the vessels 12 is executed in one cycle. The reaction liquids during the course of the reaction en route including the reaction liquids in the final state of the reaction are eventually measured in this way. The respective magnets 13 rotate integrally with the respective vessels 12 and, therefore, the antibody-immobilized magnetic material liquids (MP) are subjected to the stable reaction without receiving influence in dispersion and aggregation during the rotation.

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 magnetic microparticles.

(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 this RIA method uses radioactive elements, special equipment must be installed and the operation must be performed by a qualified operator, and there are complications such as the need for careful disposal of waste.

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

Figure 5 explains the principle of such EIA method.
First, magnetic fine particles (Magnet) on which the first reagent 2 is immobilized are
A solution of ic particle (hereinafter referred to as MP) 1 is prepared, and by dispensing six samples 4 containing the antigen 3 to be measured into this solution, the first antigen/antibody exhaustion occurs and a part of the antigen 3 is is bound to the first antibody 2. Antigen 3 that does not bind
′ exists in a free state. Therefore, using a magnet, MP
Free antigen 3' is removed in the aggregated state by adsorption of I, and so-called B/F separation is performed. Next, a second antigen-antibody reaction occurs by dispensing the second antibody (second reagent) 6 labeled with the enzyme 5, and the antigen 3 to be measured binds to MPI and a part of the enzyme-labeled antibody 6. It is then made into a sandwich. The unbound enzyme-labeled antibody 6' exists in a free state. Therefore, similar to the above, B/F separation is performed using a magnet 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 third reaction state by spectrophotometry,
This means that it is possible to measure the amount of antidote 3 that is proportional to the amount of enzyme 5.

Figure 4 shows a configuration diagram when performing immunoassay using the EIA method based on this principle. 1.1 is a circular reaction tank, and the reaction tank 11 contains the sample to be analyzed. A large number of reaction vessels 12 are arranged so as to be intermittently movable in the direction of the arrow by one pitch per cycle by a drive source (not shown). - As an example, a case is shown in which 75 reaction vessels 12 are arranged, and each reaction vessel 12
The number shown inside is the position Nα (position Nα
) means. A magnet 13 for performing B/F separation as will be described later is arranged at a desired position on the periphery of the reaction vessel 11, and a photometry section is arranged to photometer the reaction liquid in the reaction vessel 12 to measure the amount of antigen in the sample. 14 are arranged.

At position ff1Nα1, a sample containing antigen 3 to be measured is dispensed into reaction vessel 1-2, and at Nα2, antibody-immobilized magnetic fluid (MP) 1 is dispensed therein.

This causes the first immune reaction (antigen/antibody reaction) to occur. Next, Nα13, 14.15 and 17°18.19
By using the magnet 13, MPl is attracted and collected to perform the first B,/F separation, and free antigen is removed by suction. Nα with the number circled indicates the position where MPl is adsorbed.

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, when photometry is performed later by the photometry section 14,
Change the labeled enzyme to be dispensed depending on the photometric method. For example, when measuring light using an absorption method, POD is used as the labeling enzyme, and when measuring light using a luminescent method, ALP is used as the labeling enzyme. Also, use antibodies that have specificity corresponding to each measurement item.

N (135, 36, 37 and 40, 41.42 and 45
．． MP again by using magnet 13 in 46.47
Aspirate and collect I to perform a second B,/F separation, and aspirate and remove free enzyme-labeled antibody. During this time, washing was performed with Nα38,43.48, and Nα39,44
．． Stirring is carried out at 49. That is, B and /F separations are 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, respectively. During this time, stirring is performed using Nα54.

Subsequently, the reaction container 12 that has been moved at Nα 68 is caused to pass through the optical path of the light source, and the reaction liquid is measured by the photometry section 14, for example, by an absorption method. In this case M
To avoid measurement errors due to the influence of PI, attract MP with a magnet from NO.66).
The amount of antigen is measured by measuring the reaction solution with the cap removed. After the reaction, the reaction vessel 12 is cleaned at Nα69 to Nα75 and prepared for reuse.

(Problem to be Solved by the Invention) In the conventional immunoassay system, the reaction liquid in the reaction container is measured only for the reaction liquid that has moved near the final position of the reaction line in each cycle. Therefore, there is a problem that the reaction process during the process cannot be measured.

In other words, in the configuration shown in Fig. 4, the measurement is performed at Nα.
This is only for the reaction liquid in the reaction vessel that has been moved intermittently at a constant pitch every cycle at 68, and it is impossible to measure the reaction process at the previous position. Generally, in immunoassays, measurements are taken during the enzymatic reaction process, the reagent blank value of the substrate solution, the water blank value of one reaction container, etc., to check the linearity of the enzyme reaction in the case of high concentrations, and to automatically obtain stable data. Correction would be necessary, but this is not possible for the reasons mentioned above. In particular, the substrate solution that is dispensed to cause an enzymatic reaction with Nα53 and perform absorbance measurement is likely to deteriorate over time, so knowing the state of this deterioration is important when applying color correction, and if this is not possible. This results in inaccurate measurements with tonal drift.

In order to measure the reaction process in progress in this way, it is sufficient to move the entire reaction vessel by one rotation plus one pitch each cycle, but in the EIA method using magnetic particles, the arrangement of the magnet for B/F separation is Due to the fact that M
Since the set 1 dispersion of P occurs in an undesirable manner, a stable reaction is inhibited.

The present invention has been made in response to the above-mentioned problems.
The object of the present invention is to provide an immunoassay system that can measure the reaction process of a reaction solution.

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above object, the present invention provides a circular configuration in which a large number of reaction vessels for dispensing a sample and at least an antibody-immobilized magnetic particle liquid to be reacted with the sample are arranged in a circular shape. An immunoassay in which unnecessary fluid containing unreacted antigens is removed while adsorbing antibody-immobilized magnetic particles that have reacted with the antigen in the sample using magnets that are movable intermittently and placed at predetermined positions on the circumference. The system is characterized in that the magnet is configured to be movable in synchronization with the movement of the reaction container.

(Function) The magnet for performing B/F separation is configured to be movable in synchronization with the movement of the reaction vessel, and is moved, for example, by one rotation every cycle, and only the reaction vessel is moved by one pitch. This allows all reaction vessels to pass through the photometry section every cycle, making it possible to measure the reaction process in the middle of the reaction liquid in all reaction vessels, and the magnet also rotates in synchronization with the movement of the reaction vessels every cycle. Therefore, it does not affect the distribution and aggregation of MP during rotation. Furthermore, since the reaction vessel is advanced one pitch ahead in each cycle, the measurements are repeated in sequence.

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

FIG. 1 is a block diagram showing an embodiment of the immunoassay cystine of the present invention, in which 11 is a circular reaction tank, and 12 is this reaction tank 11.
A large number of reaction vessels to accommodate samples to be analyzed are arranged along the periphery of the reaction vessel 11. Magnets 13 are arranged at desired positions on the periphery of the reaction vessel 11 to perform B/F separation. 1
Reference numeral 6 denotes a first drive source that moves each reaction container 12 by one rotation plus one pitch in each cycle, and 17 moves each magnet 1-3 by one rotation in each cycle in synchronization with the movement of the reaction containers 12 arranged opposite to each other. This is the second driving source.

Before starting the measurement, for example, 75 reaction vessels 12 are placed at positions Nα from ] to 75. Among these reaction vessels 12, the magnet is placed opposite the No. reaction vessel 12 circled with 13 are arranged. Among these magnets] 3, the magnets 13 of Nα13 to 15 are for B/F separation of free antigen 3′, and the magnets 13 of Nα17
The magnets 13 from 19 to 19 are for discharging the remaining free antigen and washing solution, and the magnets 13 from Nα35 to 37 are for B/F separation of the free second reagent (enzyme-labeled antibody) 6'. , Nα40 to 42. The magnets Nα45 to 47 and Nα50 to 52 are for discharging only the remaining free second reagent and cleaning solution, and the magnets NCL66 to 68] 3 is for the optical path power of the light source ＼ MPI during measurement.
It is for removing. Each magnet 13 is held in a circular holding container 18 arranged concentrically with the reaction tank 11,
It is driven by the second drive source 17 so as to move one rotation every quarter in synchronization with the movement of the reaction container 12.

Reference numeral 14 denotes a photometric unit for measuring the amount of antigen in the sample mash of the reaction solution in each reaction container 12, and is constituted by a photometric unit based on, for example, light absorption d. In the case of the embodiment of the present invention, 75 reaction vessels 12 pass through this photometric section every cycle, resulting in 75 measurements being performed.

FIG. 2 shows the arrangement of each reaction vessel 12 and each magnet 13 after one cycle. In FIGS. 1 and 2, the △ mark indicates the position of a specific reaction vessel 12 before and after one cycle, and the mark indicates the position of a specific magnet 13 before and after one cycle. Since each magnet 13 rotates once every cycle, its position does not always change, and each reaction vessel 12 moves one rotation plus one pitch every cycle, so its position advances by one pitch to the next Nα every cycle. Magnet 1
3 may be arranged in various ways as shown in FIGS. 3(a) to 3(d). As shown in FIGS. 1 and 2, (a) is an example of the arrangement inside the reaction vessel 12, (b) is an example of the arrangement outside the reaction vessel 12, and (C) is an example of the arrangement on the inner periphery of the reaction vessel 12. (d) shows an example in which it is placed at the bottom of the reaction vessel 12. In addition, 19 is a magnet holder, 20
indicates a bearing.

Next, the operation of this embodiment will be explained.

Before starting the measurement With the reaction container 12 and the magnet 13 arranged at each position as shown in FIG.
is moved one rotation in synchronization with the movement of the reaction container 12. As a result, each reaction vessel 12 and each magnet 1 after one cycle
Each position of 3 is as shown in Fig. 2. If we pay attention to the reaction vessel 12 at Nα13 indicated by the arrow △ in Figure 1, this reaction vessel 12 will move by one rotation plus one pitch, and after one cycle will move to the △ position at Nα14. . When moving by one rotation plus one pitch, all 75 reaction vessels 12 pass through the photometry section 14, resulting in 1
- 75 measurements will be taken in a cycle. As a result, the reaction solution in the middle of the reaction process, including the reaction solution in the final state of the reaction, is measured.

Also, if we pay attention to the magnet 13 of Nα13 indicated by the arrow in FIG. The position does not change.

This also applies to the magnets 13 placed at other positions.

Similarly, when the cycle is repeated from now on, the position of the reaction vessel 12 moves one pitch at a time, but the position of the magnet [3] always remains unchanged.

As described above, by moving the magnet 13 one rotation in synchronization with the reaction vessel 12 every cycle as in this embodiment, the magnets 13 are arranged in the Nα 13 to 15 as described above.
．． Nα17 to 19. Nα35 to 37. Nα40 to 42. Nα45 to 47. Nα50 to 52. Nα66
Reaction vessels 1-2 facing positions 68 to 68 are each magnets]
Since it rotates together with 3, during rotation MPI is not affected by dispersion or aggregation and a stable reaction is performed.

With this, it is possible to measure the intermediate process of the enzyme reaction, the reagent blank value of the substrate solution, the water blank value of the two reaction vessels, etc., so it can be used to check the linearity of the enzyme reaction at high concentrations and to obtain stable data. Automatic correction becomes possible. In addition, since it is possible to know the deterioration state of the substrate liquid over time, accurate measurement values can be obtained by applying color correction.

In this example, the reaction container 12 and the magnet 13 are rotated once and only the reaction container 12 is moved by 1 pitch. However, the present invention is not limited to this, and it is also possible to synchronously rotate multiple pitches and move only the reaction container by an arbitrary pitch. . Further, the number of magnets and the number of B/F separations can be arbitrarily changed.

[Effects of the Invention] As described above, according to the present invention, the magnet is moved in synchronization with the movement of the reaction container, and only the reaction container can be moved by an arbitrary pitch, so that the reaction liquid can be moved without being affected by the magnet. It is possible to measure the intermediate process.

[BRIEF DESCRIPTION OF THE DRAWINGS] Fig. 1 is a block diagram showing an embodiment of the immunoassay system of the present invention, Fig. 2 is a block diagram showing changes in the structure of Fig. 1 after one cycle, and Fig. 3 (a ) to (d) are cross-sectional views showing an example of the arrangement of magnets used in this embodiment, FIG. 4 is a configuration diagram showing a conventional example, and FIG. 5 is an explanatory diagram of the principle of the EIA method. DESCRIPTION OF SYMBOLS 12... Reaction container, 13... Magnet, 14... Photometry part, 16... First drive part, 17... Second drive part, 18... Magnet holding container, 19... ...Magnet holder. Agent Patent Attorney Masayoshi Misawa (C) Figure

Claims (3)

[Claims] (1) A large number of reaction vessels for dispensing a sample and at least an antibody-immobilized magnetic particle liquid to be reacted with the sample are arranged so as to be movable intermittently in a circular shape, and magnets placed at predetermined positions on the circumference are used to An immunoassay system for removing an unnecessary liquid containing an unreacted antigen while adsorbing antibody-immobilized magnetic particles that have reacted with an antigen in the immunoassay system, characterized in that the magnet is configured to be movable in synchronization with the movement of the reaction container. immunoassay analysis system. (2) The immunoassay system according to claim 1, wherein an enzyme-labeled antibody solution is further dispensed into the sample. (3) The immunoassay system according to claim 1 or 2, wherein after the magnet and the reaction container are synchronously moved by a predetermined pitch, only the reaction container is further moved by a predetermined pitch.