JPH08332076A - Culture device - Google Patents

Abstract

PURPOSE: To provide a microbial culture device to be used for e.g. cell, number test, excellent in preservability, convenience in its use and culture performance and capable of picking microbes, thus wide in application range. CONSTITUTION: This culture device has such a scheme that there is provided a waterproof substrate sheet 1 which is covered with a moistureimpermeable and transparent cover film 6, and one or both of the inner faces of the sheet 1 and cover film 6 is laminated with water-absorbing resin layer (s), and the inner face of the sheet 1 is provided with a fibrous sheet 5 of specified dimension impregnated and stuck with a culture medium component for microbes. In case of being short of the adhesiveness between the water-absorbing resin layer 3 and the substrate sheet 1 or cover film 6, there may be provided adhesive layer(s) 2a and/or 2b between them. It is esp. preferable that polyethylene oxide be used as the water-absorbing resin layer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a culturing apparatus for microorganisms used for bacterial count inspection, and more particularly to a culturing apparatus which can be stored for a long period of time and is easy to use.

[0002]

2. Description of the Related Art As a method for measuring the number of microorganisms such as foods, the agar plate pour method has been conventionally used. In this method, a predetermined amount of agar medium, which had been sterilized by high-pressure steam and the temperature of which was about 45 ° C, and a separately prepared sample solution were each dispensed into a dish that had been sterilized in advance, and the mixture was allowed to pour well and left to stand. It is confirmed that the coagulation has been solidified, and the coagulation is put into an incubator or the like to culture, and after a predetermined time, the number of colonies that have developed in the petri dish is counted. However, in the case of this method, an autoclave for autoclaving the agar medium and an inspection room capable of performing a series of microbial tests aseptically are required, and the sampling and adjustment of the sample solution from the sampling of microorganisms is required. It is difficult for a beginner to accurately perform the operation of microbiological examination including pouring, pouring with a medium, culturing, and counting.

[0003] Therefore, as a result of research on a method for conducting a microbial test easily and without requiring a high degree of skill, a dry culture medium has been developed and used as one of the culture devices. Examples of such a culture device include Petri film plate [trade name of 3M] and BACcT [trade name of Shimakyu Pharmaceutical Co., Ltd.].

The former Petri film plate is composed of a waterproof flat plate and a cover film that overlaps with the flat plate. An adhesive is applied to the inner surfaces facing each other, and a cold water-soluble substance (gelling agent) is further applied. ) Powder and medium components or powder of cold water soluble substance (gelling agent) is sprayed, and then excess powder is shaken off to form a dry medium, which is further sterilized. It is a product. Then, the outline of the method of use is as follows. First, the cover film film laminated on the flat plate is lifted, and the test is performed on a dry medium composed of a cold water-soluble substance and a medium component formed on the flat plate via an adhesive layer. A predetermined amount of the liquid is inoculated, then the cover film is lowered, and a plastic spreader is pressed onto the cover film to spread the test liquid circularly and uniformly so that the liquid is absorbed. Since the gelling agent, which is a cold water-soluble substance, solidifies in about 1 minute, it is stored in the incubator as it is after being solidified, cultured at a predetermined temperature and time, and the number of generated colonies is counted. .

The latter BACcT has a waterproof flat plate and a transparent cover film covering the waterproof flat plate, and the surface of the waterproof flat plate facing the cover film is cold water soluble in the solution of the adhesive. A mixture of a gelling agent and a microbial culture medium is added, and a coating solution that is kneaded in a mud form is applied and dried to form a coating, and a fibrous water absorbent sheet is laminated on at least a part of the coating solution, and a cover film is also used. On the surface opposite to the waterproof flat plate, a mixture of a cold water-soluble gelling agent and a microbial culture medium, or a cold water-soluble gelling agent is added and kneaded to apply a coating solution to the surface of the sticking agent, and dried. After forming a coating, these are sterilized to obtain a product. The method of using this BACcT is to lift a cover film covering a waterproof flat plate, and to test on a fibrous water-absorbent sheet laminated on a coating layer of a mixture of a cold water-soluble gelling agent and a microorganism culture medium on the waterproof flat plate. Inoculate a predetermined amount of liquid. Then remove the cover film. As a result, the test liquid diffuses throughout the water-absorbent sheet due to the capillary phenomenon due to the overlapping of the fibers of the fibrous water-absorbent sheet, the culture medium of the microorganism is dissolved, and the cold water-soluble gelling agent absorbs water and gels. At this time, the fibers of the fibrous water absorbent sheet are wrapped in the gel or adhere to the gel. After that, it is placed in an incubator, cultured at a predetermined temperature and for a certain period of time, and the number of colonies generated is counted.

[0006]

The culturing apparatus as described above is convenient in use because it is not necessary to prepare a Petri dish or a medium each time when culturing a microorganism. . However, in the case of the former Petri film plate, its method of use is to lift the cover film and place the test solution on a dry medium composed of a cold water-soluble substance and a medium component formed via an adhesive layer on the flat plate. After inoculating a predetermined amount and lowering the cover film, spread the test liquid evenly by pressing it with a plastic spreader, and let the cold water-soluble substance absorb water by leaving the spreader on for about 1 minute. It forms a gel and dissolves the medium components at the same time. Therefore, with one spreader, only one sample can be processed in one minute, and if the spreader shifts, the test liquid will spread further on the dry medium.

Further, in the case of BACcT, as described above, by dropping the test liquid onto the fibrous water-absorbent sheet on the waterproof flat plate side, the test liquid spreads throughout the sheet due to the capillary phenomenon between fibers, The gelation of the cold water-soluble gelling agent and the dissolution of the culture medium thereunder are carried out. At this time, the fibers of the fibrous water absorbent sheet are wrapped in the gel or adhered to the gel. Therefore, although the spread area of the test liquid can be made substantially constant, the bacterial cells have entered the fibers of the fibrous water-absorbent sheet, and the growth of the cells proceeds in the sheet. At this time, due to the sticking agent that is not absorbed by the gelling agent, the generated colonies tend to appear blurred and unclear. For this reason,
There is a problem that counting becomes difficult when the bacterial cells grow close to each other. In addition, since the fibrous water absorbent sheet is wrapped in the gel or adheres to the gel, after culturing,
Even if fishing bacteria are required, lifting the cover film may destroy the fibrous water-absorbent sheet and prevent fishing bacteria.

The present invention has been made in view of the above problems, and an object of the present invention is that it has a preservative property as a culture device and the operation of the culture is simple, and particularly, the test liquid At the time of inoculation, it is possible to easily spread evenly over a certain area without using any special equipment, and the generated colonies can be clearly discriminated. An object of the present invention is to provide a culturing apparatus for microorganisms which has a wide range of applications and can be easily used by bacteria.

[0009]

The above-mentioned problems can be solved by the present invention described below. That is, the invention of claim 1 comprises a waterproof base sheet and a water-impermeable and transparent cover film which is placed on the base sheet, and the base sheet or the cover film is provided. It is characterized in that a water-absorbent resin layer is laminated on the inner surface, or on both inner surfaces, and further, the inner surface on the side of the base material sheet is impregnated with a medium component of a microorganism, and a fibrous sheet having a predetermined size is fixed. It consists of a microorganism culture device.

The invention of claim 2 is the apparatus for culturing a microorganism according to claim 1, wherein the water-absorbent resin layer is made of polyethylene oxide.

[0011]

As described above, the apparatus for culturing microorganisms of the present invention comprises a waterproof base sheet and a water-impermeable transparent cover film which covers the base sheet. An inner surface of either one of the films, or both inner surfaces are laminated with a water-absorbent resin layer, and further, an inner surface on the side of the base sheet is impregnated with a culture medium component of a microorganism, and a fibrous sheet having a predetermined size is fixed. It is a composition. Therefore, at the time of culturing microorganisms, the cover film of the culturing device is lifted to impregnate and adhere the medium component of the microorganisms provided on the inner surface of the base material sheet to the fibrous sheet, and a fixed amount of it is fixed using a pipette or the like. Dropping the test liquid, by lowering the cover film, the test liquid diffuses throughout the fibrous sheet due to the capillary phenomenon between the fibers, impregnates the fibrous sheet, and at the same time dissolves the fixed medium components, The water-absorbent resin layer laminated on the inner surface of the base sheet and / or the cover film is swollen and gelled, so that nutrients and water can be supplied to the microorganisms.

At this time, since the microorganisms in the test liquid are evenly dispersed and captured in the whole fibrous sheet, they can be placed in an incubator as they are for culturing and can be easily counted by culturing. Can form colonies. Also, using a water-absorbent resin as a source of water for microorganisms, for example, when using polyethylene oxide,
The gel does not stick strongly to the fibrous sheet,
Since the cover film can be freely peeled off from the base material sheet side even after the culturing, this can be easily carried out when fishing bacteria are required. The cover film is
While preventing contamination by falling bacteria during the culture operation,
It works to prevent water from evaporating from the gel.

[0013]

The present invention will now be described in detail with reference to the drawings and examples. FIG. 1, FIG. 2 and FIG. 3 are schematic cross-sectional views showing the configuration of an embodiment of the culture apparatus of the present invention.
The present invention is not limited to these. In the culture device of FIG. 1, a grid pattern (not shown) for facilitating the counting of colonies is printed on the base material sheet 1, and the adhesive layer 2a and the water-absorbent resin layer 3 are laminated in this order. To form a main body sheet 4, and a fibrous sheet 5 with a medium is further provided on the main body sheet 4 to form a main body portion, and an adhesive layer 2b and a water-absorbent resin layer 3 are laminated in this order on one surface of a cover film 6 The cover sheet 7 is superposed so that the water-absorbent resin layer 3 is in contact with the medium-attached fibrous sheet 5 on the body sheet 4, and the body sheet 4 and the cover sheet 7 are joined at one end so that the cover sheet 7 can be opened and closed. This is a configuration in which and are joined by heat bonding or an adhesive. In the above structure, the adhesive layer 2a,
2b can be omitted if it is not necessary. Further, the cover sheet 7 can be used as a separate body without being joined to the main body sheet 4. If a displacement occurs during the culture, problems such as contamination by falling bacteria and evaporation of water in the gel may occur, so it is preferable to bond them.

The culture apparatus of FIG. 2 has the same structure as that of the culture apparatus of FIG. 1 in the main body part, that is, a grid pattern (not shown) is printed on the base sheet 1, and the adhesive layer 2a is formed thereon. , A water-absorbent resin layer 3 is laminated in order to form a main body sheet 4, a fibrous sheet 5 with a medium is further provided on the main body sheet to form a main body portion, and a cover film 6 alone is superposed on the main body portion, The cover film 6 is joined at one end so that it can be opened and closed. Also in this case, the adhesive layer 2a may be omitted if unnecessary.

In the culturing apparatus of FIG. 3, a water absorbent resin layer is not provided on the main body side, a cell pattern (not shown) is printed on the base material sheet 1, and the fibrous sheet 5 with a medium is placed thereon. A cover sheet 7 which is provided as a main body part, and an adhesive layer 2b and a water-absorbent resin layer 3 are sequentially laminated on one surface of the cover film 6 on the main body part.
The water-absorbent resin layer 3 is superposed so as to come into contact with the fibrous sheet 5 with a medium provided on the substrate sheet 1, and the cover sheet 7 is joined to the substrate sheet 1 at one end so that the cover sheet 7 can be opened and closed. Is. Even in this configuration, the adhesive layer 2b
May be omitted if not required.

The constituent materials and the like of the culture apparatus of the present invention will be described below. Base Material Sheet The base material sheet 1 is required to have waterproofness, for example, polyester, polypropylene, polyethylene,
A plastic sheet such as polystyrene, polycarbonate, or polyvinyl chloride, or a laminate of these can be used. These plastic sheets may be uncolored and transparent, but they are preferable because those colored white are easy to observe colonies and easy to count. In addition to the plastic sheet, water-resistant paper can also be used. For example, paper coated with synthetic resin or extrusion-coated, or laminated with plastic film can be used.

The substrate sheet 1 is preferably flat without curling, and its thickness is not particularly limited, but is usually in the range of 50 to 500 μm, and 80 to 80 μm.
About 300 μm is more preferable. It is preferable to print a grid pattern on the base sheet 1 in advance with an ink that is insoluble in water and does not affect the growth of microorganisms, from the viewpoint of facilitating the counting of colonies. The printing plate type is not particularly limited and may be anything, but a wide selection range of colorants, resins, solvents and the like, and when laminating a water-absorbent resin layer or the like in post-processing,
Productivity is better when processed continuously in the form of a roll, and in consideration of these factors, rotary gravure printing or the like capable of roll-up printing is preferred. As for the size of the cells, a size of 1 cm square is usually appropriate.

Cover Film The cover film 6 is waterproof and water vapor impermeable, and at the same time, it is preferable that the cover film 6 is transparent because it is common to count colonies through the cover film 6 after culturing microorganisms. It is possible to use a plastic film such as polypropylene, polyethylene, polyester, polystyrene, polycarbonate, or polyvinyl chloride as mentioned in the base sheet 1. Further, in the culture test, the cover film 6 is lifted from the base material sheet 1 to drop the test liquid, and therefore, the cover film 6 is preferably made of a material having a suitable flexibility and a thickness. Therefore, the thickness of the cover film 6 is preferably about 10 to 200 μm, and 2
It is more preferably about 0 to 100 μm.

When the water-absorbent resin layer 3 or the like is laminated on the base sheet 1 or the cover film 6, it is necessary to appropriately bond them, and if the adhesiveness is insufficient,
The laminated surface of the base sheet 1 or the cover film 6 can be subjected to pretreatment such as corona discharge treatment or anchor coating. In addition, the base sheet 1 and the cover film 6
Has a suitable gas permeability depending on the type of microorganism to be cultured,
It is preferable to mainly have oxygen permeability, and when judged together with the water vapor impermeability, at least one of the base sheet 1 and the cover film 6 has polyethylene,
It is preferable to use a polyolefin such as polypropylene.

Water-Absorbent Resin Layer In the present invention, the water-absorbent resin layer 3 laminated on the inner surface of either one of the base sheet 1 and the cover film 6 or both inner surfaces absorbs the water content of the test liquid during culturing. It forms a gel suitable for culturing microorganisms, captures the microorganisms, and supplies the absorbed water to the microorganisms. In addition, the base material sheet 1 and the cover film 6 to be laminated
It is also necessary to have a moderate adhesiveness to. As such a water absorbent resin, specifically, polyethylene oxide, electron beam cross-linking type polyacrylamide, carboxymethyl cellulose and the like can be used. Among these, polyethylene oxide is capable of forming a good gel and at the same time has no strong tackiness and can easily peel off the cover film 6 from the side of the base material sheet 1 even after culturing, so that it is easy to catch bacteria, and polyethylene oxide is a solution at the time of production. In addition to being able to be applied as a film, it can be formed into a film by itself using an inflation molding machine or a T-die extrusion machine, or can be formed into a film by blending it with another resin, which is particularly preferable in terms of excellent processability. Therefore, the method of laminating the water-absorbent resin layer 3 includes a method of applying a solution of the water-absorbent resin, drying and laminating the same, a method of extruding and coating the water-absorbent resin and further laminating the water-absorbent resin into a film. Any method can be used, such as a method in which the material is made into a laminate and is laminated by dry lamination using an adhesive.

The thickness of the water-absorbent resin layer 3 varies depending on the type of resin, but is usually in the range of about 25 to 100 μm, preferably 40 to 80 μm. If the water-absorbent resin layer 3 is provided on the inner surfaces of both the base sheet 1 and the cover film 6, the total thickness of both should be within this range. When the thickness of the water-absorbent resin layer 3 is less than 25 μm, it is not preferable because the water absorbing ability is insufficient and it takes a long time to absorb water, and when the thickness is 100 μm or more, it is not necessary and waste of material is also caused. Not preferable. still,
Water-absorbent resin layer 3 and substrate sheet 1 or cover film 6
In the case where the adhesiveness with the is weak, adhesive layers 2a, 2b may be provided between the two as an intermediate layer for improving the adhesiveness.

Fibrous sheet In the culturing apparatus of the present invention, the fibrous sheet provided in the uppermost layer of the main body part in a certain size has a sufficient amount of the medium component for microorganisms, usually about 4 g / m ^2. Impregnated,
When the test liquid is fixed and inoculated with the test liquid, it is uniformly diffused and permeated to the entire area by the capillary phenomenon between the fibers to dissolve the fixed medium components, and also the water-absorbent resin in contact therewith. It serves to supply water to the layer 3 to form a gel, and normally, a non-woven fabric or paper having a water absorbing property can be used. In addition to rayon, non-woven fabrics using polyolefin fibers can be used as non-woven fabrics.
A rayon-based nonwoven fabric is preferable because it has excellent hydrophilicity and the test solution can be diffused quickly. As the filter paper, one having a good water absorption property is suitable, and a paper having a surface coat or a paper having a strong size effect is not preferable, and a paper such as a filter paper is suitable. The thickness of the fibrous sheet may be determined in consideration of the retention ability of the medium components, the visibility of the grown colonies, etc., and the basis weight of the non-woven fabric and the basis weight of the paper are about 10 to 30 g / m ^2. Those with a relatively thin range are suitable.

A medium and the like such a fibrous sheet is impregnated with a nutrient component (medium component) of microorganisms and adhered thereto to obtain a fibrous sheet 5 with a medium. And, as the nutrient component of the microorganism, for example, yeast extract, peptone, dipotassium hydrogen phosphate, glucose, lactose, sodium chloride and the like can be used, and appropriately selected according to the microorganism to be grown from these, It can be mixed and used in a predetermined ratio. The method of impregnating and fixing these to the fibrous sheet is
There is no particular limitation, and for example, the above nutrients are dissolved or suspended in a liquid such as water or a mixed system of water-ethyl alcohol at a predetermined ratio to prepare an impregnating liquid, which is publicly known as a fibrous sheet. Alternatively, the fibrous sheet may be dipped in an impregnating solution to be impregnated therewith, and then pulled up and lightly scraped off of the excess solution with a bar or the like, and dried.

The size of such a fibrous sheet 5 with a medium is usually a circle having a diameter of about 5 cm when the amount of the test liquid to be inoculated on the fibrous sheet 5 is 1 ml. It is preferable in that the medium suitable for culture can be formed by uniformly diffusing and permeating the entire surface of the attached fibrous sheet 5. The medium-attached fibrous sheet 5 is provided on the uppermost layer of the main body of the culturing device, but a solution such as a water-absorbent resin may be used instead of the adhesive and applied in a spot shape to the main body side to be bonded. Of course, it can also be used by simply sandwiching it between the main body sheet 4 or the base sheet 1 and the cover sheet 7.

In addition to the nutrient components of the microorganism, it is also effective to add a dye that can be metabolized by the microorganism. Such a dye is metabolized by a microorganism that grows in the course of culturing, and colonies are colored, so that it has an effect of making it easy to count the number of colonies. Specific examples of such dyes include triphenyltetrazolium chloride (hereinafter referred to as TTC), p-tolyltetrazolium red, tetrazolium violet, and petetryltetrazolium blue.

As a method of applying the above dye to the culture apparatus of the present invention, for example, when impregnating and adhering the nutrient component of the microorganism to the fibrous sheet, the dye is added to the impregnating liquid of the nutrient component in advance. Then, the fibrous sheet may be impregnated with the nutritional component and dried to be fixed. When the water-absorbent resin layer 3 is applied with a solution of the water-absorbent resin, dried and laminated. Alternatively, the dye may be added in advance to the solution of the water absorbent resin, and the dye may be applied and dried to be contained in the water absorbent resin layer 3. As another method, in the case of a structure in which the water-absorbent resin layer 3 is laminated only on the inner surface of either the base sheet 1 or the cover film 6, a coating solution of a dye alone using a water-absorbent resin as an adhesive is separately used. The dye layer may be formed by applying the dye to the inner surface of the cover film 6 or the substrate sheet 1 on the side where the water-absorbent resin layer 3 is not laminated, and drying the dye.

In the culture device of the present invention, the main body sheet 4
The cover sheet 7 and the cover sheet 7 are preferably joined at one end so as not to shift the overlapped position, but the joining method is not particularly limited, that is, the main body sheet 4
Alternatively, it is possible to freely select and join a suitable method depending on the materials of the inner surface of the base sheet 1 and the inner surface of the cover sheet 7. For example, when a polyethylene oxide layer is laminated as a water-absorbent resin layer on both inner surfaces, the polyethylene oxide itself has thermal adhesiveness, so that the layers can be joined by heat sealing. Also, when the material of the inner surface of the main body side and the inner surface of the cover sheet side are different, they can be joined by applying a tape-like adhesive, a double-sided adhesive tape, or an adhesive, and by applying a heat-sealing agent such as a so-called part coat agent. It can also be joined by heat sealing or a pressure sensitive adhesive on both sides.

Specific examples of the culturing apparatus of the present invention will be given below to actually carry out a culturing test, and the performance thereof will be described in comparison with a pour method using a standard agar medium. [Example 1] (Production of main body sheet) After printing a grid pattern having a pitch of 1 cm on a surface of a cup base paper having a basis weight of 160 g / m ² by a gravure printing method, low density polyethylene (hereinafter referred to as LDPE) was formed on both surfaces thereof. (Displayed as) (Mirason 16SP manufactured by Mitsui Petrochemical Co., Ltd.) is used as a base sheet of laminated paper extruded and coated to a thickness of 20 μm, and the LDPE on the side where the grid printing is applied.
LDPE (Milason 16SP) as an adhesive layer on the layer
And polyethylene oxide (Aquacork Sumitomo Seika)
The resin blended in a weight ratio of 6: 4 was extrusion-coated to a thickness of 20 μm, and polyethylene oxide (Aquacoke) alone as a water-absorbent resin layer was applied to a thickness of 40 μm.
Extrusion coating was carried out with m and laminated to prepare a main body sheet.

(Creation of cover sheet) A biaxially oriented polypropylene film having a thickness of 25 μm (manufactured by OPU-1 Tocello) (one-sided corona discharge treatment) was used as a cover film as a base material of the cover sheet, and the corona discharge treatment was performed. As a bonding layer on the surface, polypropylene (hereinafter referred to as PP) (HIPOL L-840 manufactured by Mitsui Petrochemical Co., Ltd.) and polyethylene oxide (Aquacoke) in a weight ratio of 10:
The blended resin of No. 4 has a thickness of 20 by the inflation method.
The film formed to a thickness of μm is laminated by a dry lamination method using a urethane adhesive, and the coating liquid for the water-absorbent resin layer having the following composition is further coated on it with a comma coater to obtain a solvent-containing coating amount before drying. 20 g / m ² is applied and dried at a drying temperature of 80 ° C. to obtain a water absorbent resin layer (TT
(Including C) to prepare a cover sheet. Composition of coating liquid for water-absorbent resin layer Polyethylene oxide (Aquacork Sumitomo Seika) 10% by weight ethanol solution 1000 parts by weight Dye TTC 0.2 parts by weight

(Preparation of Fibrous Sheet with Medium) As a base material for the fibrous sheet, a rayon-based non-woven fabric (Claflex NA220-JP0359 basis weight 17 g / m ² ) was used and immersed in a standard liquid medium having the following composition. After impregnation, the both surfaces were lightly squeezed with a bar to remove excess liquid, and dried at 60 ° C. to prepare a fibrous sheet having a solid medium content of 4 g / m ² . Standard liquid medium composition Peptone 10 parts by weight Yeast extract 5 parts by weight Glucose 2 parts by weight Pure water 195 parts by weight

The main body sheet, the cover sheet, and the fibrous sheet with a culture medium prepared as described above are respectively formed into a rectangular shape having a length of 7 cm and a width of 8 cm, and the cover sheet has a length of 7 cm.
It was cut into a rectangle with a width of 8.5 cm, and the medium-attached fibrous sheet was cut into a circle with a diameter of 5 cm to prepare a member for a culture device. Next, the members of the main body sheet and cover sheet,
The water-absorbent resin layers are overlapped so that the surfaces overlap each other inward, and the cover sheet is lapped at the other end so that one end of the cover sheet projects from the main body sheet by 0.5 cm. The inner surfaces were attached to each other with a double-sided tape having a width of 6 mm. The protruding portion of the cover sheet, which protrudes 0.5 cm from the main body sheet, is used as a handle for lifting the cover sheet during culture or the like. And
After the fibrous sheet member with a culture medium was inserted between the main body sheet and the cover sheet that were stuck together as described above, sterilization by γ-ray irradiation was performed to prepare the culture device of Example 1.

Example 2 (Preparation of Main Body Sheet) Base material sheet having a basis weight of 160 g
/ M ² cup base paper with a grid pattern of 1 cm each on the surface printed by gravure printing, then LDPE on both sides
(Mirason 16SP, manufactured by Mitsui Petrochemical Industry), thickness 20
A laminated paper extruded to a thickness of μm was prepared. In addition, LDPE (Mirason 16SP) and polyethylene oxide (Aquacork Sumitomo Seika) are used as an adhesive layer in a weight ratio of 6:
The resin blended in No. 4 has a thickness of 20 by the inflation method.
A film having a thickness of 60 μm was prepared by forming a film having a thickness of 60 μm using polyethylene oxide (Aqua Coke) alone as a water-absorbent resin layer. The above base sheet was cut into a rectangle measuring 7 cm in length x 8 cm in width, and the films of the adhesive layer and the water absorbent resin layer were each cut into a circle having a diameter of 6 cm. And one end of its long side (8 cm) is left as an adhesive portion with the cover film for a width of 1 cm, and an adhesive layer film (thickness 20 μm) and a water-absorbent resin cut in the above-mentioned circular shape in the approximate center of the remaining 7 cm square. Layer films (thickness 60 μm) were placed one on top of the other, and they were thermocompression bonded from above with a hot plate to thermally bond them to prepare a main body sheet in which a base material sheet, an adhesive layer, and a water absorbent resin layer were laminated in this order.

(Preparation of cover sheet) A cover film is a biaxially oriented polypropylene film (OPU-1 Tocello) having a thickness of 50 μm and subjected to corona discharge treatment on one side.
A TTC coating solution having the following composition was applied on the corona discharge treated surface by a reverse roll coater so that the coating amount including the solvent before drying was 10 g / m ² , dried with hot air at 100 ° C., and irradiated with an electron beam. I made a cover sheet. Composition of TTC coating liquid Polyacrylamide 10% by weight aqueous solution 1000 parts by weight Dye TTC 0.4 parts by weight (fibrous sheet with medium) The same fibrous sheet with medium prepared in Example 1 was used as it was. Cut the above cover sheet into a rectangle measuring 7 cm in length and 8.5 cm in width,
On the circular water-absorbent resin layer (thickness: 60 μm) having a diameter of 6 cm, the main body sheet is overlaid so that the TTC-coated surfaces of the cover sheet overlap each other, and only one end of the cover sheet is 0.5. So that they stick out at the other end so that they stick out, and the inner surfaces at the ends that are aligned are stuck together with a 6 mm wide double-sided tape, and then a circular water-absorbent resin layer with a diameter of 6 cm of the main body sheet Diameter 5 in the upper center
Insert the fibrous sheet with medium cut into a circle of cm,
This was irradiated with γ-rays and sterilized to obtain the culture device of Example 2.

Example 3 (Preparation of Main Body Sheet) Thickness of 120 μm as base material sheet
Polypropylene sheet (one side corona discharge treatment) is used, and a grid pattern with a pitch of 1 cm is printed on the corona discharge treated surface by gravure printing, and TT of the following composition is printed on it.
The coating solution C was coated with a reverse roll coater so that the coating amount including the solvent before drying was 10 g / m ^2, and the temperature was 100 ° C.
It was dried with hot air and was irradiated with an electron beam to prepare a main body sheet. Composition of TTC coating liquid Polyacrylamide 10% by weight aqueous solution 1000 parts by weight Dye TTC 0.4 parts by weight

(Preparation of Cover Sheet) As a cover film which is a base material, a biaxially stretched polypropylene film having a thickness of 25 μm (manufactured by OPU-1 Tocello) (single-sided corona discharge treatment) is used, and the corona-discharge-treated surface is As the adhesive layer, a blend resin of PP (Hypol L-840 Mitsui Petrochemical Industry Co., Ltd.) and polyethylene oxide (Aquacork Sumitomo Seika Chemical Co., Ltd.) in a weight ratio of 10: 4 was formed into a film having a thickness of 20 μm by an inflation method, and a urethane film was formed. After laminating by a dry lamination method using a system adhesive, this laminated sheet was cut into a rectangle having a length of 7 cm and a width of 8.5 cm. In order to laminate a water-absorbent resin layer on the adhesive layer surface of this laminated sheet, a film of polyethylene oxide (Aquacoke) having a thickness of 60 μm is formed by an inflation method and cut into a circle having a diameter of 6 cm to be used as a water-absorbent resin layer. It was a film. Next, a width of 1 cm is provided at one end on the long side (8.5 cm) side of the adhesive layer surface of the laminated sheet as an adhesive portion with the main body sheet, and at the other end is 0.5 cm as a handle portion of the cover sheet. Take the width, put the film of the water-absorbent resin (polyethylene oxide) cut in the circular shape in the center of the remaining area of 7 cm in length × 7 cm in width, heat press bond it with a hot plate, and heat bond it to create a cover sheet. did.

(Fibrous sheet with medium) The same fiber sheet with medium prepared in Example 1 was used as it was. The TTC-coated surface of the main body sheet prepared as described above and the water-absorbent resin layer surface of the cover sheet are overlapped so as to overlap with each other, and an adhesive portion (1 cm width) with the main body sheet is attached to one end of the long side of the cover sheet. The main body sheet and the cover sheet are aligned at the end of the side where they are provided, and the inner surfaces of the aligned ends are pasted together with a double-sided tape having a width of 6 mm. A 5 cm circular cut fibrous sheet with a medium was inserted into a position covered with a circular water absorbent resin layer laminated on the inner surface of the cover sheet, and this was sterilized by γ-ray irradiation to obtain the culture device of Example 3. did.

[Culture test and its results] Using each of the five culture devices of Examples 1, 2, and 3 prepared as described above, the bacterial solution prepared by the following method was sterilized with a sterilized pipette to each 1 ml. , Inoculate on the fibrous sheet with each medium,
After covering with a cover sheet, it was placed in an incubator adjusted to 37 ° C. and cultured for 48 hours. Separately from the examples, using the bacterial solution prepared by the same method as the examples below for comparison, 1 ml of each was prepared by the conventional pour method, and 20 ml of each standard agar medium prepared in 5 petri dishes was prepared. A comparative sample was prepared by pouring into the mixture and cultured under the same conditions as in the examples.

Preparation of Bacterial Fluid Escherichia coli was used as a strain and a liquid medium (NUTRIENT BROT
The cells were shake-cultured in H) at 37 ° C. for 24 hours, and the bacterial solution was diluted with sterile physiological saline so that the number of bacteria was 10 ² / ml to prepare a bacterial solution used in the culture test. Example 1 above,
The number of colonies generated by the culture test of 2, 3 and comparative samples was counted, and the respective data and the average value are shown in Table 1.
It was shown to.

[0039]

[Table 1] Bacteria count measurement result (E. coli) [unit: pieces]

As is clear from the results of the culture tests shown in Table 1, the results of the culture tests using the culture devices of Examples 1, 2, and 3 of the present invention were conducted using the standard agar medium prepared by the conventional pour method. The results are substantially in agreement with the results of the culturing test of the comparative sample, which shows that the culturing performance is good, the operation is easy, and the culturing device is sufficiently practical and practical. Further, the colonies that were generated could be clearly observed because the fibrous sheet was relatively thin, and counting could be performed easily. After the culture, the cover films of the samples of Examples 1 to 3 could be easily peeled off from the base material sheet side, and it was easy to catch bacteria.

[0041]

As described in detail above, the culture device of the present invention comprises a waterproof base sheet and a water-impermeable transparent cover film covering the base sheet, and the base sheet and the cover film. The water absorbent resin layer is laminated on either one of the inner surfaces or both inner surfaces, and the inner surface on the side of the base material sheet is further provided with a fibrous sheet impregnated with and adhered to the culture medium of the microorganism. By adopting such a configuration,
When culturing microorganisms, simply lift the cover sheet of the culture device, inoculate a fixed amount of the test liquid on the fibrous sheet impregnated and adhered with the medium with a pipette, and then lower the cover sheet to remove the test liquid. Is uniformly dispersed in the entire area of the fibrous sheet of a predetermined area due to the capillary phenomenon between the fibers, dissolves the medium components, and at the same time, is absorbed on either the inner surface of the base sheet or the cover film, or on both inner surfaces. The functional resin layer is swollen and gelled, nutrients and water can be supplied to the microorganisms, and culture is possible. Therefore, operations such as heating dissolution and high-pressure sterilization for medium adjustment are unnecessary, and even a skilled technician can easily carry out a culture test such as a microorganism test. Before use, it is in a sterilized and dry state and can be stored for a long period of time, and can be rapidly tested at any time.

The fibrous sheet is relatively thin, and the gel-forming material is a water-absorbent resin such as polyethylene oxide, and even when it gels, it does not strongly adhere to the fibrous sheet, so that it is dispersed uniformly. Colonies can be formed in a clear state, counting is easy, and after culturing, the cover film can be easily peeled off from the base material sheet side, so that bacteria can be freely picked up. In addition, it is possible to easily incinerate in terms of disposability after use, and it is possible to easily provide a culture device excellent in usability and performance.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing the configuration of an embodiment of a culture device of the present invention.

FIG. 2 is a schematic cross-sectional view showing the configuration of another embodiment of the culture apparatus of the present invention.

FIG. 3 is a schematic cross-sectional view showing the configuration of still another embodiment of the culture device of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Base material sheet 2a, 2b Adhesive layer 3 Water-absorbent resin layer 4 Main body sheet 5 Fiber sheet with culture medium 6 Cover film 7 Cover sheet 8 Joint part

Claims (2)

[Claims] 1. A waterproof base sheet, and a water-impermeable and transparent cover film that covers the base sheet, and the inner surface of either or both of the base sheet and the cover film. Laminate a water-absorbent resin layer on the inner surface,
A culturing apparatus for microorganisms, comprising a fibrous sheet which is impregnated with and adhered to a medium component of microorganisms on the inner surface of the substrate sheet side. 2. The apparatus for culturing microorganisms according to claim 1, wherein the water-absorbent resin layer is made of polyethylene oxide.