JP4564822B2 - Reaction vessel and automatic analyzer using the same - Google Patents

Description

  The present invention relates to an automatic analyzer for quantitatively or qualitatively analyzing biological samples such as blood and urine, and more particularly to a reaction container for reacting a sample and a reagent and an automatic analyzer equipped with the same.

  The automatic analyzer uses a reagent that changes color when it reacts with the measurement target component in the sample. The sample and reagent are mixed in the reaction vessel, and the progress of the reaction is measured based on the change in absorbance of the light transmitted through the reaction solution. is doing. Generally, plastic or glass is used as the material for the reaction vessel. Some plastic reaction containers have poor wettability when the plasticizer used at the time of molding remains on the surface, and air bubbles tend to stick to the inner surface of the reaction container. There is a concern that if a bubble is formed in a portion through which the light beam is transmitted, a large error is given to the measurement result. On the other hand, a glass reaction container may have too good wettability. In that case, the liquid surface height that can be measured by transmission is reduced because the U-shaped phenomenon (meniscus) of the liquid surface becomes intense due to the capillary action of the liquid, and when the reaction liquid is small, the liquid surface is sufficient to the luminous flux height of the photometer. Height cannot be secured, and there is a limit to reducing the amount of the reaction solution. In particular, in recent automatic analyzers, the diameter of the reaction vessel (reaction cell) tends to be reduced in order to reduce the amount of the reaction solution, so that the influence of the meniscus is increasing.

  In addition, since glass has too high wettability compared to plastic, when the reaction vessel is washed and reused, there is a concern that a so-called carryover may occur in which the previous reaction solution remains without being sufficiently washed.

  Patent Document 1 discloses a technology for removing bubbles by irradiating bubbles attached to the reaction vessel wall surface with ultrasonic waves.

JP 2004-45113 A

  The technique described in Patent Document 1 is capable of preventing the adhesion of bubbles even when a plastic reaction vessel is used. However, if a dedicated ultrasonic irradiation device is provided for removing bubbles, there is a concern about high costs. .

  It is desirable that the reaction vessel itself has both advantages of plastic and glass without using such an aggressive mechanism. The object of the present invention is to prevent bubbles from adhering to the portion of the photometer inside the reaction vessel where light flux is transmitted, to reduce the amount of the reaction solution, and to keep the reaction solution carry-over due to insufficient washing of the reaction vessel low. It is another object of the present invention to provide a reaction container for an automatic analyzer and an automatic analyzer using the same.

  A surface treatment for improving wettability is performed on a part of the inner wall of the plastic reaction vessel (the light transmitting portion and its periphery). As a method of improving wettability, a method of immersing ozone water on the surface is preferable. Further, in order to perform only a part, masking or the like is performed so that the wettability should not be improved so that ozone water is not applied.

  According to the present invention, it is possible to prevent bubbles from adhering to the translucent portion of the inner surface of the reaction vessel and perform highly reliable analytical photometry.

  In addition, since the wettability is improved only in the translucent part of the reaction vessel and its vicinity, the reaction solution level is flattened so that light can be measured even with a small amount of reaction solution, and the reaction solution is carried over by the reaction vessel. You can hold down even less.

  In the current automatic analyzer, a method is used in which a sample is dispensed into a reaction vessel, a reagent is added to the reaction vessel, and the mixture is stirred and the change in absorbance of the reaction solution is measured to quantitatively analyze the components contained in the sample. . As shown in FIG. 1, the absorbance is measured by a photometer 5 at the moment when the reaction vessel 1 is arranged on the reaction disk 2 and the reaction vessel crosses the optical axis 4 emitted from the lamp 3.

  When the reagent is discharged and added from the reagent nozzle 11 or when the reaction solution is stirred, air bubbles are often involved. If air bubbles adhere to the light transmitting portion on the inner surface of the reaction vessel, a large error will occur in the photometric accuracy. If the wettability of the reaction vessel is poor, bubbles 9 are likely to adhere to the inner surface (FIG. 2). Even in this case, if the wettability is good on the inner surface of the reaction vessel, the bubbles float without being attached.

  Further, in order to secure the light quantity, the optical axis 4 of this photometer needs to have a certain width and height. Otherwise, the amount of light cannot be reduced, and the S / N of the photometer will deteriorate. In order to achieve a reduction in reagent amount, which is a recent user requirement, the reaction liquid surface is often designed to be lowered to the limit of the optical axis. If glass is used as the material of the reaction vessel or if the entire inner surface of plastic is made to have good wettability, the liquid level 10 of the reaction liquid becomes U-shaped as shown in FIG. The problem that it ends up occurs. Therefore, it is not possible to use glass or plastic with improved wettability on the entire inner surface. Therefore, as shown in FIG. 1, the wettability is improved only in the portion that becomes the light-transmitting surface of the plastic reaction container (the places where the wettability was improved in FIG. 1 are 6 and 7). Then, by securing a slightly larger amount of the reaction liquid than the optical axis translucent part, the liquid surface 11 of the reaction liquid becomes horizontal and flat as shown in FIG. By doing so, the maximum amount of light can be secured and measured with a minimum amount of reaction solution. Further, a plastic reaction vessel using glass or having good wettability on the entire inner surface has a drawback that the carry-over of the reaction vessel becomes large. Carryover means that when a reaction vessel is washed and reused for the next analysis, the washing becomes insufficient and the previous reaction solution remains and contaminates the next reaction solution. When washing the reaction vessel, it is necessary to wash the entire reaction vessel, so the washing solution is poured into the mouth. If the entire inner surface has good wettability, a slightly mixed liquid of the reaction solution and the cleaning solution remains over the entire inner surface (a kind of adsorption) and carry-over increases. According to the present embodiment shown in FIG. 1, the carry-over can be greatly reduced because the wettability is improved only in a part such as the vicinity of the light-transmitting portion (area ratio is about 1/15). In addition, recently, reaction liquid is often agitated by ultrasonic non-invasive stirring, and by using the ultrasonic stirring element used for stirring the reaction liquid, the reaction container in the cleaning liquid is irradiated with ultrasonic waves. If so, the cleaning can be performed sufficiently. The ultrasonic irradiation range may be only the translucent part with good wettability, and this part is at a height that must be irradiated with ultrasonic waves to stir the reaction solution, and stirring and washing are one stirring element. You can do two birds with one stone. As the plastic used for the reaction vessel, cyclic polyolefin resin, polycarbonate resin, acrylic resin, and polystyrene resin are suitable.

  A method for improving the wettability of a part of the inner surface of the reaction vessel is shown in FIG. By immersing the ozone liquid, the activity value of the surface changes and it becomes very easy to get wet. A piping bush 12 made of rubber for flowing ozone solution is inserted into the reaction vessel. When inserted, the close contact portion 15 is pressed against the inner surface of the reaction vessel so that the ozone liquid does not leak from the close contact portion. The ozone liquid flows from the inlet 13 and is discharged from the outlet 14. By doing so, the ozone liquid flows in contact with the inner surface of the translucent surface. As a result, the wettability of the inner surfaces 6 and 7 in the vicinity of the translucent part at the bottom of the reaction vessel is improved.

  In addition, there is a plasma irradiation method as a method for improving wettability.

  In the present invention, since the wettability is improved between the translucent portion on the inner surface of the reaction vessel and the periphery thereof, bubbles are less likely to adhere to the translucent portion. Further, the inner surface of the reaction vessel near the minimum liquid level remains poor in wettability, so that the meniscus can be small, so that the liquid level is kept flat and the liquid level necessary for photometry is secured. In addition, only a part of the translucent surface is used to improve the wettability, and the increase in carryover due to this is minimized (the amount of carryover is the case when the entire inner wall of the reaction vessel is made wettable. 1/20).

The figure which shows the photometry partial structure of the automatic analyzer which implements this invention. The figure which shows the mode of the liquid in the reaction container when wettability is bad. The figure which shows the mode of the liquid in reaction container when wettability is too good. The figure which shows the mode of the liquid in the reaction container at the time of invention implementation. The figure which shows an example of the surface treatment method (wetting property improvement method) in this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Reaction container, 4 ... Optical axis, 6 ... Inner surface which improved wettability, 8 ... Reaction liquid surface, 9 ... Air bubble, 16 ... Ozone water.

Claims (4)

A reaction vessel for mixing a sample and a reagent,
Reaction vessel of the inner wall of the reaction vessel, wettability of the portion where the light flux of the light meter is transmitted, characterized in that the light flux of the inner wall may compared with the wettability of the portion which does not transmit. The reaction vessel according to claim 1, wherein
A reaction vessel characterized in that the shape of the wettable portion of the inner wall of the reaction vessel is circular or square according to the luminous flux shape of the photometer. In the reaction container according to claim 1 or 2,
The reaction vessel is one selected from cyclic polyolefin resin, polycarbonate resin, acrylic resin, and polystyrene resin. Sample dispensing means for dispensing the sample into the reaction vessel;
Measuring means for measuring a change in the optical properties of the liquid in the reaction vessel;
In an automatic analyzer equipped with
An automatic analyzer comprising the reaction container according to any one of claims 1 to 3.

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