Freestanding low protein adsorption container

Abstract

To provide a self-standing type low protein adsorption container in which adsorption of proteins and cells to the inner surface of the container forming a storage area is reduced.SOLUTION: Provided is a self-standing type low protein adsorption container comprising a planar bottom and side walls made of a resin material, and can stand on its own with the bottom placed on a mounting surface. The inner surface of the bottom and the inner surface of the sidewalls form a containment area for containing liquid. Furthermore, a coating layer made of a water-soluble resin having a hydrophilic functional group in a side chain is formed on the inner surfaces of the bottom and side walls and bridges are formed between the water-soluble resins and between the water-soluble resin and the inner surfaces of the bottom and side walls.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a free-standing low protein-adsorption container. [Background technology]

[0002] Biochemical containers used for protein analysis, cell culture, storage, etc. are often made of resin materials. However, biochemical containers made of resin materials may be prone to protein and cell adsorption on the inner surface of the container. In clinical tests, if proteins contained in collected urine, blood, etc. are adsorbed to the inner surface of the storage container, the test value and recovery amount of the protein may be lower than the actual value, which may lead to an erroneous diagnosis. In addition, if cells are adsorbed to the inner surface of the container during culture or storage, it may be difficult to recover the cells from the container, and the recovery rate may be reduced.

[0003] To solve such problems, a method for treating the inner surface of a biochemical vessel to make it difficult for proteins and cells to be adsorbed (low-adsorption treatment method) is known. For example, Patent Document 1 discloses a method in which a polystyrene member is placed in a reaction vessel, ozone gas is passed through the member, oxygen is introduced to the surface to make it hydrophilic, and the adsorption of proteins to the surface of the polystyrene member is reduced. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 10-101820 Summary of the Invention [Problem to be solved by the invention]

[0005] However, it is known that the hydrophilic polar group formed by oxygen and introduced onto the surface of the resin layer by the method described in Patent Document 1 penetrates into the interior of the resin layer over time upon contact with the gas phase, and there was a problem that the effect decreased over time.

[0006] Furthermore, since free-standing containers typically have a free-standing surface (flat bottom) with a certain or greater area, even when the inner surface of the container has been subjected to the above-mentioned low-adsorption treatment, there is still room for further improvement in terms of protein and cell recovery loss, and there is particularly room for improvement in large-capacity free-standing containers.

[0007] The present invention has been made in consideration of the above-mentioned problems, and aims to provide a free-standing low-protein adsorption container that has low adsorption of proteins and cells to the inner surface of the container that forms the storage area. [Means for solving the problem]

[0008] The free-standing low-protein-adsorption container of the present invention has a planar bottom and side walls made of a resin material, is capable of standing on its own with the bottom placed on a support surface, the inner surfaces of the bottom and the side walls form a storage area for storing a liquid containing proteins or cells, and is characterized in that the inner surfaces of the bottom and the side walls are formed with a coating layer made of a water-soluble resin having a hydrophilic functional group in its side chain, and the water-soluble resin is crosslinked between itself and between the water-soluble resin and the inner surface of the bottom and the inner surface of the side walls. Effect of the Invention

[0009] According to the present invention, a self-supporting low protein adsorption container can be obtained which has low adsorption of proteins and cells to the inner surface of the container forming the storage area, thereby making it possible to reduce recovery losses of these proteins and cells. [Brief description of the drawings]

[0010] [Figure 1]FIG. 1 is a schematic perspective view of a free-standing low protein adsorption container according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a schematic perspective view showing a state in which a sample (liquid containing proteins or cells) is being collected by a pipette from the free-standing low protein adsorption container according to the present embodiment. [Diagram 3] 1 is a schematic enlarged cross-sectional view showing an enlarged view of the inner surface of the container in the storage area of ​​the free-standing low protein adsorption container according to the present embodiment. FIG. [Figure 4] 1 is a schematic cross-sectional view showing the vicinity of a storage area of ​​a free-standing low protein adsorption container according to the present embodiment. [Diagram 5] 13 is a schematic cross-sectional view showing the vicinity of the storage area of ​​a modified example of the free-standing low protein adsorption container according to the present embodiment. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, an embodiment of a self-supporting low protein adsorption container according to the present invention will be described with reference to the drawings. The embodiment described below is merely an example for facilitating understanding of the present invention, and is not intended to limit the present invention. In other words, the shapes, dimensions, arrangements, and other aspects of the components described below may be modified or improved without departing from the spirit of the present invention, and the present invention naturally includes equivalents thereof. In addition, in all drawings, similar components are given the same reference numerals, and duplicate explanations are omitted as appropriate. Note that in all drawings, some parts are not given reference numerals (omitted) for convenience. Furthermore, the dimensional ratios of each member shown in the drawings may differ from the actual dimensional ratios in order to facilitate understanding of the invention.

[0012] <Summary> First, an overview of the free-standing low protein-adsorption container according to this embodiment will be described in detail with reference to Fig. 1 and Fig. 2. Fig. 1 is a perspective view that typically shows a free-standing low protein-adsorption container 100 according to this embodiment. Fig. 2 is a perspective view that typically shows a state in which a liquid 43 (sample) containing proteins or cells is being collected by a pipette 41 from the free-standing low protein-adsorption container 100 according to this embodiment.

[0013] The free-standing low protein adsorption container 100 according to this embodiment includes a planar bottom 11 and sidewalls 13 made of a resin material as shown in Fig. 1 and Fig. 2, and is free-standing when the bottom 11 is placed on a placement surface, and the inner surface 11a of the bottom 11 and the inner surface 13a of the sidewalls 13 form a storage area 21 for storing a liquid 43 containing proteins or cells. Furthermore, the inner surface 11a of the bottom 11 and the inner surface 13a of the sidewalls 13 are provided with a coating layer 51 made of a water-soluble resin having a hydrophilic functional group in the side chain, and the water-soluble resin is cross-linked between the water-soluble resins and between the inner surface 11a of the bottom 11 and the inner surface 13a of the sidewalls 13. The "inner surface" refers to the surface on the inner side of the container (the storage area 21 side) of each member of the free-standing low protein adsorption container 100 according to this embodiment.

[0014] The free-standing low protein adsorption container 100 according to this embodiment may have at least the bottom 11 and the side wall 13 made of a resin material. Here, "made of a resin material" means that the resin material is contained as the main material (the resin material is contained in an amount of 70% by mass or more, more preferably 80% by mass or more, and even more preferably 90% by mass or more of the total mass of the member), and may contain materials other than the resin material, such as additives, within a range that does not affect the effects of the present invention. The free-standing low protein adsorption container 100 according to this embodiment may be entirely made of a resin material (all of the members provided therein), or at least a part of the members other than the bottom 11 and the side wall 13 may be made of a material other than a resin material (for example, glass, etc.), but it is more preferable that the free-standing low protein adsorption container 100 according to this embodiment is entirely made of a resin material (particularly the same resin material). This is because the free-standing low protein adsorption container 100 according to this embodiment is easy to manufacture (blow molding, injection molding, etc.).

[0015] Examples of the resin material include polyolefin resins or cyclic polyolefin resins such as polypropylene resin, polyethylene resin, polymethylpentene resin, and ethylene-propylene copolymer, polystyrene resins such as polystyrene and acrylonitrile-butadiene-styrene resin, polyacrylic resins such as polyethylene terephthalate resin and polybutylene terephthalate resin, methacrylic resins such as polymethyl methacrylate resin, fluorine resins such as polytetrafluoroethylene, acrylic resins such as polyacrylonitrile, cellulose resins such as propionate resin, polycarbonate resin, vinyl chloride resin, polyarylate resin, polysulfone resin, polyethersulfone resin, polyetheretherketone resin, and polyetherimide resin. These may be used alone or in combination of two or more. Among these, polyethylene terephthalate resin is particularly preferred from the viewpoint of moldability, transparency, radiation resistance (sterility), and the like required for biochemical containers.

[0016] The weight average molecular weight of the resin material is not particularly limited, but is preferably from 10,000 to 500,000, and more preferably from 20,000 to 100,000. When the weight average molecular weight of the resin material used is within this range, the moldability is superior.

[0017] The weight average molecular weight is a value measured by size exclusion chromatography (Gel Permeation Chromatography system, Shodex KF-800 column, both manufactured by Showa Denko KK, elution solvent: tetrahydrofuran).

[0018] Using such a resin material as the main material, the bottom 11 and side wall 13 of the free-standing low protein adsorption container 100 of this embodiment can be formed, for example, by blow molding, injection molding, injection blow molding, vacuum molding, etc., and even the entire free-standing low protein adsorption container 100 of this embodiment can be formed.

[0019] The shape of the freestanding low protein adsorption container 100 according to this embodiment is not limited as long as it has a planar (approximately planar) bottom 11 and a side wall 13 connected to the bottom 11, can stand on its own when the planar bottom 11 is placed on a mounting surface, and the inner surface 11a of the bottom 11 and the inner surface 13a of the side wall 13 form a storage area 21 for storing a liquid 43. For example, it may be a substantially rectangular bottle shape having a planar bottom 11 and side wall 13 as shown in Fig. 1 and Fig. 2, or may be a substantially cylindrical bottle shape in which the side wall 13 is configured by a curved surface. In addition, it may be a flask shape (such as an Erlenmeyer flask shape in which the side wall 13 tapers from the mounting surface side to the upper part) in which the bottom 11 is planar, a petri dish shape, or the like. In addition, the storage area 21 of the free-standing low protein adsorption container 100 in this embodiment may be formed not only by the inner surface 11a of the bottom 11 and the inner surface 13a of the side wall 13, but also by the inner surface of another member (for example, the inner surface of the top portion).

[0020] The free-standing low protein-adsorption container 100 according to this embodiment may be provided with one or more openings 31 that can serve as an inlet or outlet for a sample or the like, a degassing port, etc. The openings 31 may have a structure that allows them to be repeatedly opened and closed, and may have a structure in which a screw thread is provided on the openings 31 and that allows them to be sealed with a cap 33 or the like, as shown in Figures 1 and 2. Furthermore, the free-standing low protein-adsorption container 100 according to this embodiment may be provided with other members (for example, a gripping portion, etc.) besides the above.

[0021] Furthermore, the freestanding low protein-adsorption container 100 of this embodiment may have a capacity in the storage area 21 that can store more than 50 mL, or even more than 100 mL, or even more than 200 mL of liquid 43 containing protein or cells. That is, the storage area 21 of the freestanding low protein-adsorption container 100 of this embodiment may have a capacity that can store more than 50 mL of a sample liquid containing protein or a liquid culture medium containing cells, and can store, react, culture, etc. in this storage area 21. Therefore, for example, if the opening 31 has a structure that can be sealed, the volume of the storage area 21 itself may be more than 50 mL, and if the opening 31 has a structure that cannot be sealed, the volume may be such that the storage area 21 does not interfere with subsequent work when it stores more than 50 mL of liquid 43 (a volume that does not easily spill out of the opening 31 during processing, etc.). The freestanding low protein adsorption container 100 of this embodiment is characterized in that, even though it is such a large-capacity container, there is little adsorption of proteins and cells to the inner surface of the container that forms the storage area 21, and the liquid 43 is easily recovered from the storage area 21, resulting in little recovery loss, etc.

[0022] <Configuration of the container inner surface forming the storage area> Next, the configuration of the container inner surface forming the storage area 21 of the free-standing low protein-adsorption container 100 according to this embodiment will be described in detail with reference to Fig. 3 to Fig. 5. Fig. 3 is a schematic enlarged cross-sectional view showing the container inner surface (the inner surface 11a of the bottom 11 or the inner surface 13a of the side wall 13) in the storage area of ​​the free-standing low protein-adsorption container 100 according to this embodiment. Fig. 4 and Fig. 5 are schematic cross-sectional views showing the vicinity of the storage area 21 in two different embodiments of the free-standing low protein-adsorption container 100 according to this embodiment.

[0023] In the freestanding low protein adsorption container 100 according to this embodiment, a coating layer 51 made of a water-soluble resin having a hydrophilic functional group in a side chain is formed at least on the inner surface 11a of the bottom 11 and the inner surface 13a of the side wall 13 forming the storage area 21. The water-soluble resins are cross-linked between each other, that is, between the molecules of the water-soluble resin in the coating layer 51, and between the water-soluble resin (the water-soluble resin molecules in the coating layer 51) and the inner surface 11a of the bottom 11, and between the water-soluble resin and the inner surface 13a of the side wall 13. By forming such a coating layer 51, the surface layer of the container inner surface forming the storage area 21 contains a hydrophilic functional group, and proteins and cells contained in the liquid 43 stored in the storage area 21 are less likely to be adsorbed to the container inner surface forming the storage area 21.

[0024] In this embodiment, the "water-soluble resin" refers to a resin that is hydrated by ionic or hydrogen bonds with water molecules and dissolves in water, and is capable of dissolving at least 1.0 g in 100 g of water at 25° C. In addition, the "coating layer 51 made of a water-soluble resin" refers to a coating layer 51 that contains the above-mentioned water-soluble resin as a main component (e.g., 80% by mass or more, or even 90% by mass or more), and includes a coating layer 51 in which the water-soluble resin contained in the coating layer 51 is crosslinked and hardened to become water-insoluble. In other words, the coating layer 51 may be crosslinked and hardened to become water-insoluble, so long as it is formed using a material containing a water-soluble resin as a main component.

[0025] Examples of water-soluble resins having a hydrophilic functional group in the side chain include saponified polyvinyl acetate, polyvinylpyrrolidone, polyethylene glycol, polyacrylamide, polymethacrylamide, polyhydroxyethyl methacrylate, polypentaerythritol triacrylate, polypentaerythritol tetraacrylate, polydiethylene glycol diacrylate, copolymers of monomers constituting them, copolymers of 2-methacryloyloxyethyl phosphorylcholine and other monomers (e.g., butyl methacrylate, etc.). These water-soluble resins also include those to which another hydrophilic functional group or the like is added as a side chain. Among these, one or more selected from saponified polyvinyl acetate, polyvinylpyrrolidone, and polyethylene glycol are more preferred. This is because it is possible to suppress stimulation to proteins and cells and further improve their quality. The average degree of polymerization of this water-soluble resin is not particularly limited, but is preferably 100 to 10,000, and more preferably 200 to 5,000, because this makes it easier to form a uniform coating on the inner surface of the container that forms the storage area 21 and improves workability.

[0026] Examples of the saponified polyvinyl acetate include polyvinyl alcohol or a copolymer of vinyl alcohol and other compounds, and saponified vinyl acetate modified with a hydrophilic group, a hydrophobic group, an anion, a cation, an amide group, or a reactive group such as an acetoacetyl group, and vinyl alcohol. The degree of saponification of the saponified polyvinyl acetate is not particularly limited, but is preferably 20 to 100 mol %, more preferably 50 to 95 mol %, of the entire polyvinyl acetate.

[0027] The water-soluble resin constituting the coating layer 51 has a hydrophilic functional group in the side chain, and may further have a functional group for crosslinking or curing, or the functional group for crosslinking or curing may be a hydrophilic functional group or a part thereof. Examples of such functional groups include functional groups containing a hydroxyl group or a carbonyl group (such as a carboxy group, an aldehyde group, a ketone group, an ester group, or an amide group), and functional groups reactive to radiation, photosensitive, or thermally reactive. Furthermore, functional groups containing a diazo group, an azide group, a diazide group, or the like, which are photosensitive hydrophilic functional groups, are more preferable.

[0028] In particular, water-soluble resins having functional groups containing azide groups and / or carbonyl groups in the side chains are more preferred, water-soluble resins having functional groups containing aromatic azide groups and / or carbonyl groups in the side chains are even more preferred, and water-soluble resins represented by the following formula (Ia) or (Ib) are even more preferred, because they can be easily crosslinked and cured by irradiation with light having a wavelength of 300 to 500 nm and can further reduce the amount of adsorption of proteins, cells, etc.

[0029] [ka]

[0030] [ka]

[0031] In the above formula (Ia), R1 represents a hydrocarbon group having a carbonyl and an amine, R2, R3, R4, and R5 each represent a hydrogen atom or an alkyl group, r1 represents 1 to 1000, r2 represents 40 to 4995, r3 represents 0 to 4000, and n represents 1, 2, or 3. In particular, it is more preferable that R2, R3, R4, and R5 each represent a hydrogen atom. In the above formula (Ib), R represents a hydrocarbon group having a carbonyl and an amine, r1 represents 1 to 1,000, r2 represents 40 to 4,995, and r3 represents 0 to 4,000.

[0032] Furthermore, the water-soluble resin represented by the above formula (Ia) is more preferably a water-soluble resin represented by the following formula (IIa). In the following formula (IIa), R represents an alkyl group having a carbonyl and an amine, r1 represents 1 to 1000, r2 represents 40 to 4995, r3 represents 0 to 4000, and n represents 1, 2, or 3.

[0033] [ka]

[0034] Using the water-soluble resin having a hydrophilic functional group in the side chain as described above, a coating layer 51 is formed on at least the inner surface 11a of the bottom 11 and the inner surface 13a of the side wall 13, which form the storage area 21, of the freestanding low protein adsorption container 100 according to this embodiment. Note that a coating layer 51 made of the water-soluble resin as described above may also be formed on the inner surfaces of other members (for example, the inner surface of the top part, etc.).

[0035] The coating layer 51 is formed by coating the inner surface 11a of the bottom 11 and the inner surface 13a of the side wall 13 with the water-soluble resin, and crosslinking and curing the molecules of the water-soluble resin contained in the coating layer 51 by light irradiation or the like. That is, the water-soluble resin in the coating layer 51 is crosslinked with each other (for example, the crosslinked structure 61 in FIG. 3). This crosslinking is preferably formed by functional groups of the side chains of the water-soluble resin. Note that the coating layer 51 may contain some molecules of the water-soluble resin that are not crosslinked, and it is sufficient that the coating layer 51 is crosslinked and cured to such an extent that the structure of the coating layer 51 can be maintained. This makes it possible to reduce the amount of elution from the coating layer 51 when the liquid 43 is contained in the storage area 21, and to obtain a coating layer 51 that is resistant to physical stimuli, and the low adsorption ability (low adsorption to proteins and cells) of the coating layer 51 is maintained for a long period of time. Here, the crosslinked structures 61 in FIG. 3 are merely illustrative of the crosslinked structures between the molecules of the water-soluble resin, and do not represent the actual size or number of the crosslinked structures.

[0036] Furthermore, in the self-supporting low protein adsorption container 100 according to this embodiment, not only the water-soluble resins constituting the coating layer 51 are cross-linked with each other, but also the water-soluble resins constituting the coating layer 51 and the inner surface 11a of the bottom 11 and the inner surface 13a of the side wall 13 (for example, cross-linked structure 63 in FIG. 3). This cross-link is preferably formed by a functional group of the side chain of the water-soluble resin and a functional group (such as a functional group formed by a surface treatment described later) of the inner surface 11a of the bottom 11 or the inner surface 13a of the side wall 13. This results in the coating layer 51 having high adhesion to the inner surface of the container. In other words, the stability of the coating layer 51 is increased. Here, the cross-linked structure 63 in FIG. 3 is also an easy-to-understand representation of the cross-linked structure between the molecules of the water-soluble resin and the inner surface 11a of the bottom 11 or the inner surface 13a of the side wall 13, and does not represent the actual size or number of the cross-linked structure.

[0037] The inner surface 11a of the bottom 11 and the inner surface 13a of the sidewall 13 on which the coating layer 51 is formed may be subjected to a surface treatment such as hydrophilization or a surface treatment functional group formation treatment before the coating layer 51 is formed. Such a surface treatment is, for example, a treatment for forming an oxygen-containing functional group. By forming the oxygen-containing functional group on the surface, the above-mentioned crosslinking (crosslinking with the water-soluble resin of the coating layer 51, the crosslinked structure 63 in FIG. 3) is more easily formed. Examples of the oxygen-containing functional group include polar functional groups such as carbonyl groups (carboxy groups, aldehyde groups, ketone groups, ester groups, etc.), hydroxyl groups, ether groups, peroxy groups, and epoxy groups. In particular, it is more preferable that a treatment for forming a carbonyl group is performed as the oxygen-containing functional group. In addition, for example, plasma treatment, corona discharge treatment, excimer laser treatment, flame treatment, etc. can be adopted as the surface treatment, and it is particularly preferable to perform plasma treatment.

[0038] The amount of oxygen-containing functional groups formed by the above treatment is not particularly limited, but is preferably 0.01 to 100 nmol / cm 2 is preferred, and particularly 0.05 to 10 nmol / cm 2If the amount of oxygen-containing functional groups is less than this lower limit, the desired effect may not be fully exhibited, whereas if the amount exceeds the upper limit, the properties of the bottom 11 or side wall 13 itself may change, making it impossible to satisfy the performance requirements for a biochemical container.

[0039] In particular, it is preferable that the water-soluble resin constituting the coating layer 51 has a side chain containing an aromatic azide group and a side chain containing a carbonyl group, that carbonyl groups are formed on the inner surface 11a of the bottom 11 and the inner surface 13a of the side wall 13, and that crosslinks are formed between the aromatic azide group of the water-soluble resin and the carbonyl group of the water-soluble resin, and between the aromatic azide group of the water-soluble resin and the carbonyl groups of the inner surface 11a of the bottom 11 and the inner surface 13a of the side wall 13. This is because these crosslinks are very easy to form, and tend to result in a more stable coating layer 51.

[0040] The thickness of the coating layer 51 is not particularly limited, but is preferably 0.1 to 50 μm, and more preferably 0.5 to 20 μm. Here, the "thickness of the coating layer 51" refers to the shortest distance from the surface of the coating layer 51 (the surface on the housing area 21 side) to the surface in contact with the inner surface 11a of the bottom 11 and the inner surface 13a of the sidewall 13. The same applies hereinafter. The thickness of the coating layer 51 is measured by an ellipsometer.

[0041] It is preferable that the thickness of the coating layer 51 is uniform on the inner surface 11a of the bottom 11, uniform on the inner surface 13a of the sidewall 13, and that the thickness of the coating layer 51 on the inner surface 11a of the bottom 11 and the coating layer 51 on the inner surface 13a of the sidewall 13 are uniform. When the thickness of the coating layer 51 is uniform on the inner surface 11a of the bottom 11 and the inner surface 13a of the sidewall 13 as a whole, the difference in the adsorption ability of proteins and cells depending on the location in the storage area 21 is very small, and chemical reactions, enzyme reactions, cell culture, etc. in the storage area 21 can be performed extremely stably. Here, "uniform thickness" means that the variation in the measured values ​​(difference between maximum and minimum) when the thickness of the coating layer 51 is measured at 10 arbitrary locations on the inner surface 11a of the bottom 11 or the inner surface 13a of the sidewall 13 is within 0.1 μm, more preferably within 0.05 μm.

[0042] For example, as shown in FIG. 4, it is very preferable that the coating layer 51 formed on the inner surface 11a of the bottom 11 is uniform in thickness, and that the coating layer 51 formed on the inner surface 13a of the side wall 13 is also uniform in thickness, and further, that both the coating layer 51 formed on the inner surface 11a of the bottom 11 and the coating layer 51 formed on the inner surface 13a of the side wall 13 are uniform in thickness, i.e., the coating layers 51 formed on the inner surface 11a of the bottom 11 and the inner surface 13a of the side wall 13 are all uniform in thickness.

[0043] Alternatively, it is preferable that the thickness of the coating layer 51 is gradually increased from the center toward the end side in contact with the side wall 13 on the inner surface 11a of the bottom 11, and further that the thickness of the coating layer 51 is gradually increased from the lower side in contact with the bottom 11 toward the upper side on the inner surface 13a of the side wall 13. When liquid 43 containing proteins and cells is sucked up and collected from the storage area 21 using a pipette 41 or the like, proteins and cells tend to gather in the center of the bottom 11 where the coating layer 51 is relatively thin, and by sucking up using a pipette 41 or the like at the center of the bottom 11 as shown in FIG. 2, the proteins and cells can be collected more easily and the collection loss is reduced.

[0044] For example, as shown in Fig. 5, it is preferable that the thickness of the coating layer 51 formed on the inner surface 11a of the bottom 11 is gradually increased from the center of the bottom 11 toward the end side in contact with the side wall 13, and further, the thickness of the coating layer 51 formed on the inner surface 13a of the side wall 13 is gradually increased from the lower side in contact with the bottom 11 toward the upper side. Also, although not limited thereto, it is more preferable that the thickness of the coating layer 51 at the end of the bottom 11 is thinner than the thickness of the coating layer 51 at the lower part of the side wall 13. In other words, it is more preferable that the thickness of the coating layer 51 is gradually increased from the center of the bottom 11 toward the upper side of the side wall 13, as in the embodiment of Fig. 5.

[0045] In the above embodiment, the same effect as above can be achieved even if the thickness of the coating layer 51 at the end of the bottom 11 is the same as the thickness of the coating layer 51 at the lower part of the side wall 13. Also, in the above embodiment, the thickness of the coating layer 51 at the lower part of the side wall 13 may be thinner than the thickness of the coating layer 51 at the end of the bottom 11. This makes it possible to prevent the upper coating layer 51 on the inner surface 13a of the side wall 13 from becoming thicker than necessary.

[0046] On the other hand, in the free-standing low protein adsorption container 100 according to this embodiment, the thickness of the coating layer 51 may be gradually thinner from the center toward the end side in contact with the side wall 13 on the inner surface 11a of the bottom 11. That is, the thickness of the coating layer 51 may be the thickest at the center on the inner surface 11a of the bottom 11. Also, the thickness of the coating layer 51 may be gradually thinner from the lower side in contact with the bottom 11 toward the upper side on the inner surface 13a of the side wall 13. That is, the thickness of the coating layer 51 on the lower side on the inner surface 13a of the side wall 13 may be the thickest.

[0047] The embodiment of the thickness of the coating layer 51 on the inner surface 11a of the bottom 11 and the embodiment of the thickness of the coating layer 51 on the inner surface 13a of the sidewall 13 may be a combination other than the combination of the above-mentioned embodiments. For example, the thickness of the coating layer 51 formed on the inner surface 11a of the bottom 11 may be uniform or gradually thinner from the center of the bottom 11 toward the end side in contact with the sidewall 13, and further, the thickness of the coating layer 51 formed on the inner surface 13a of the sidewall 13 may be gradually thicker from the lower side in contact with the bottom 11 toward the upper side.

[0048] In the freestanding low protein adsorption container 100 according to this embodiment, in which the container inner surface forming the storage area 21 is configured as described above, proteins and cells are less likely to be adsorbed to the container inner surface forming the storage area 21, and liquid 43 containing proteins and cells can be easily recovered from this storage area 21, thereby reducing recovery loss of proteins and cells, etc. Another feature is that recovery is easy even if the container has a large capacity.

[0049] The protein or cell adsorption rate in the storage area 21 of the freestanding low protein adsorption container 100 according to this embodiment is not limited, but is preferably 20% or less in terms of protein adsorption rate, more preferably 10% or less, and even more preferably 5% or less (for example, 0.0001 to 10%, or even 0.0002 to 5%). When the adsorption rate is within such a range, it can be more suitably used as a specimen storage container for clinical testing, etc.

[0050] The protein adsorption rate is calculated using the following formula (1). Adsorption rate (%) = adsorbed amount / total amount of protein in solution (1)

[0051] Specifically, iodine ( 125I) Labeled bovine serum immunoglobulin G is diluted with phosphate buffer (pH 7.4) to concentrations of 1.0E-6 g / mL, 1.0E-7 g / mL, and 1.0E-8 g / mL to prepare each solution, and a predetermined amount of each solution is dispensed into the storage area 21 of the freestanding low protein adsorption container 100 according to this embodiment and allowed to stand for 1 hour at 37° C. Thereafter, washing is repeated three times with phosphate buffer containing 0.05 v / v% Tween 20, and measurement is performed using a gamma ray counter. Then, the amount of iodine remaining on the inner surface of the container ( 125 I) The weight (adsorption amount) of the labeled bovine serum immunoglobulin G is determined, and the adsorption rate at each solution concentration is calculated using the above formula (1), and the average value is calculated.

[0052] <Manufacturing method for self-supporting low protein adsorption container> Next, a method for producing the self-supporting low protein adsorption container 100 according to this embodiment will be described.

[0053] In the method for manufacturing the self-supporting low protein adsorption container 100 according to the present embodiment, first, a container having a desired shape (a shape that can stand on its own when the planar bottom 11 is placed on a mounting surface) having a planar bottom 11 and sidewalls 13 is formed by blow molding or the like using a material made of the resin material as described above. If necessary, a member such as an opening 31 may be provided. Then, a coating layer 51 is formed on the inner surface 11a of the bottom 11 and the inner surface 13a of the sidewalls 13 of the obtained container using a material containing a water-soluble resin as a main component as described above. Note that it is preferable to form the coating layer 51 after subjecting the inner surface 11a of the bottom 11 and the inner surface 13a of the sidewalls 13 to a surface treatment such as plasma treatment under an oxygen atmosphere.

[0054] Examples of methods that can be used to form the coating layer 51 made of a water-soluble resin on the inner surface 11a of the bottom 11 and the inner surface 13a of the sidewall 13 include spin coating, dipping, and dispensing a water-soluble resin solution into the storage area 21 and then tilting the container to drain the solution. By using such a method, the coating layer 51 can be formed by contacting the inner surface 11a of the bottom 11 and the inner surface 13a of the sidewall 13 with a solution of a material containing a water-soluble resin as a main component, and then drying the remaining solvent, etc.

[0055] In this case, the water-soluble resin is preferably used as a solution prepared using a solvent so that the viscosity at 20°C is preferably 1 mPa·s or more and 10 mPa·s or less, more preferably 2 mPa·s or more and 7 mPa·s or less. The solvent in this case is water, or a mixture of water and an organic solvent can be used to increase the solubility. When the viscosity of the water-soluble resin solution used is within the above range, a coating layer 51 having excellent low adsorption ability for proteins and cells can be easily obtained.

[0056] Furthermore, the remaining solvent and the like can be dried, for example, by a method in which the opening 31 of the freestanding low protein adsorption container 100 according to this embodiment is oriented downward (in the direction of gravity). As described above, it is more preferable to perform drying while adjusting the thickness of the coating layer 51 formed on the inner surface 11a of the bottom 11 and the inner surface 13a of the side wall 13 so that the thickness is uniform throughout, or the thickness of the coating layer 51 on the inner surface 13a of the bottom 11 gradually increases from the center toward the end, and the thickness of the coating layer 51 on the inner surface 13a of the side wall 13 gradually increases from the lower side toward the upper side.

[0057] Then, a process is performed in which the water-soluble resins of the formed coating layer 51 are crosslinked and cured between each other and between the water-soluble resin and a predetermined inner surface of the container, thereby modifying the resin into a water-insoluble cured coating. This process can be performed by the above-mentioned light irradiation process, heat treatment, radiation irradiation process, etc., and may be appropriately selected depending on the workability, the characteristics of the water-soluble resin constituting the coating layer 51, and the types of functional groups formed on the inner surface 11a of the bottom 11 and the inner surface 13a of the side wall 13, etc. Among these, the light irradiation process (UV irradiation process, etc.) is a method that can quickly perform crosslinking and curing processes and can be performed with simple equipment.

[0058] The light source for crosslinking and curing the coating layer 51 by light irradiation is not particularly limited, but is preferably a light source with an illuminance of 5.0 mW / cm 2 Ultra-high pressure mercury lamp or 0.1mW / cm 2 A UV lamp with a power of 5.0 mW / cm can be used. Crosslinking and curing by light irradiation can be controlled by the illuminance and exposure time, so if a light source with low illuminance is used, the exposure time can be extended, and if a highly reactive photosensitive group is selected, crosslinking and curing can also be performed under a fluorescent lamp. For example, 2 When using an ultra-high pressure mercury lamp, the radiation intensity is 0.1 mW / cm for 1 to 10 seconds. 2 When using a UV lamp, 3 to 10 minutes of irradiation can sufficiently crosslink and harden the resin.

[0059] In this manner, by modifying the coating layer 51 into a water-insoluble cured coating, it is possible to construct a stable coating layer 51 having hydrophilic functional groups on the surface layer. Then, by forming the coating layer 51 in which the water-soluble resin is coated in advance on the inner surface 11a of the bottom portion 11 and the inner surface 13a of the side wall portion 13 by the method described above, the layer is crosslinked and cured to modify it into a water-insoluble cured coating, whereby the coating layer 51 of a predetermined thickness can be easily obtained.

[0060] Incidentally, at least a part of the unreacted water-soluble resin may be removed by washing the surface of the coating layer 51 with water or an aqueous solvent after curing by crosslinking. For example, if elution of uncrosslinked water-soluble resin or the like is confirmed, the amount of elution can be reduced by adding a washing step of the coating layer 51 after curing.

[0061] Furthermore, if necessary, a sterilization treatment is performed on the self-supporting low protein adsorption container 100 according to this embodiment on which the above-mentioned coating layer 51 is formed. Examples of the sterilization method include ethylene oxide gas (EOG) sterilization, dry heat sterilization, steam sterilization, and radiation sterilization, but radiation sterilization using gamma rays or electron beams is preferred, and in the case of mass production, gamma ray sterilization is particularly preferred from the viewpoint of radiation transparency.

[0062] Although there are no particular limitations on the absorbed dose of radiation, if the absorbed dose is too low, there is a possibility that sufficient sterilization cannot be performed, and if the absorbed dose is too high, there is a possibility that the container body, the coating layer 51, etc. may deteriorate, so for example, the absorbed dose is preferably from 1 kGy to 50 kGy, and particularly preferably from 5 kGy to 30 kGy. This allows the free-standing low protein adsorption container 100 according to this embodiment to be sterilized while maintaining its characteristics.

[0063] By using the above-described manufacturing method, it is possible to manufacture the free-standing low-protein-adsorption container 100 of this embodiment, which has low adsorption of proteins and cells to the inner surface 11a of the bottom 11 and the inner surface 13a of the side wall 13 that form the storage area 21.

[0064] The above embodiment encompasses the following technical ideas. (1) A self-supporting low-protein-adsorption container for containing a liquid including proteins or cells, the container having a planar bottom and side walls made of a resin material, capable of standing on its own when the bottom is placed on a support surface, the inner surfaces of the bottom and the side walls forming a storage area for holding the liquid, and further, the inner surfaces of the bottom and the side walls are formed with a coating layer made of a water-soluble resin having a hydrophilic functional group in its side chain, and the water-soluble resins are cross-linked with each other and with the water-soluble resin and with the inner surfaces of the bottom and the side walls. (2) A free-standing low-protein-adsorption container as described in (1), wherein the coating layer on the inner surface of the bottom portion has a uniform thickness, the coating layer on the inner surface of the side wall portion has a uniform thickness, and further, the coating layer on the inner surface of the bottom portion and the coating layer on the inner surface of the side wall portion have uniform thicknesses. (3) A self-supporting low protein adsorption container as described in (1), wherein, on the inner surface of the bottom, the thickness of the coating layer gradually increases from the center toward the end side that contacts the side wall, and, on the inner surface of the side wall, the thickness of the coating layer gradually increases from the lower side that contacts the bottom toward the upper side. (4) The self-supporting low protein-adsorption container according to any one of (1) to (3), wherein the storage area has a volume capable of storing more than 50 mL of the liquid. (5) A free-standing low-protein-adsorption container according to any one of (1) to (4), wherein the water-soluble resin constituting the coating layer has a side chain containing an aromatic azide group and a side chain containing a carbonyl group, carbonyl groups are formed on the inner surface of the bottom and the inner surface of the side wall, and the aromatic azide group of the water-soluble resin and the carbonyl group of the water-soluble resin, and the aromatic azide group of the water-soluble resin and the carbonyl group on the inner surface of the bottom and the inner surface of the side wall are crosslinked. (6) The self-supporting low protein-adsorption container according to any one of (1) to (5), wherein the water-soluble resin constituting the coating layer is a water-soluble resin represented by formula (Ia) or formula (Ib) above. [Explanation of symbols]

[0065] 100 Self-supporting low protein adsorption container 11 Bottom 11a Bottom inner surface 13 Side wall 13a Inner surface of side wall 21 Containment Area 31 Opening 33 Cap 41 Pipette 43 Fluids containing proteins or cells 51 Covering layer 61 Crosslinked structure (water-soluble resin-water-soluble resin) 63 Crosslinked structure (water-soluble resin - inner surface)

Claims

1. A vessel for containing a liquid containing proteins or cells, The container has a flat bottom and sidewalls made of a resin material, The bottom part is self-supporting when placed on a placement surface, an inner surface of the bottom portion and an inner surface of the side wall portion form a storage area for storing the liquid; Further, a coating layer made of a water-soluble resin having a hydrophilic functional group in a side chain is formed on the inner surface of the bottom portion and the inner surface of the side wall portion, and the water-soluble resins are crosslinked with each other and with the inner surface of the bottom portion and the inner surface of the side wall portion, On the inner surface of the bottom portion, the thickness of the coating layer gradually increases from the center toward the end portion in contact with the side wall portion, On the inner surface of the side wall portion, the thickness of the coating layer gradually increases from a lower side in contact with the bottom portion toward an upper side, a thickness of the coating layer at an end of the bottom portion in contact with the side wall portion is thinner than a thickness of the coating layer at a lower portion of the side wall portion in contact with the bottom; Freestanding, low protein adsorption container.

2. A vessel for containing a liquid containing proteins or cells, The container has a flat bottom and sidewalls made of a resin material, The bottom part is self-supporting when placed on a placement surface, an inner surface of the bottom portion and an inner surface of the side wall portion form a storage area for storing the liquid; Further, a coating layer made of a water-soluble resin having a hydrophilic functional group in a side chain is formed on the inner surface of the bottom portion and the inner surface of the side wall portion, and the water-soluble resins are crosslinked with each other and with the inner surface of the bottom portion and the inner surface of the side wall portion, On the inner surface of the bottom portion, the thickness of the coating layer gradually increases from the center toward the end portion in contact with the side wall portion, On the inner surface of the side wall portion, the thickness of the coating layer gradually increases from a lower side in contact with the bottom portion toward an upper side, The thickness of the coating layer at the lower part of the side wall portion in contact with the bottom is equal to the thickness of the coating layer at the end part of the bottom portion in contact with the side wall portion, or is thinner than the thickness of the coating layer at the end part of the bottom portion in contact with the side wall portion. Freestanding, low protein adsorption container.

3. 3. The free-standing low-protein-adsorption container according to claim 1 or 2, wherein the storage area has a volume capable of storing more than 50 mL of the liquid.

4. the water-soluble resin constituting the coating layer has a side chain containing an aromatic azide group and a side chain containing a carbonyl group, a carbonyl group is formed on the inner surface of the bottom portion and the inner surface of the side wall portion, The free-standing low protein-adsorption container according to any one of claims 1 to 3, wherein the aromatic azide group of the water-soluble resin is crosslinked with the carbonyl group of the water-soluble resin, and the aromatic azide group of the water-soluble resin is crosslinked with the carbonyl group of the inner surface of the bottom and the inner surface of the side wall.

5. The self-supporting low protein adsorption container according to any one of claims 1 to 4, wherein the water-soluble resin constituting the coating layer is a water-soluble resin represented by the following formula (Ia) or the following formula (Ib): 【Chemistry 1】 (In formula (Ia), R1 represents a hydrocarbon group having a carbonyl and an amine, R2, R3, R4, and R5 each represent a hydrogen atom or an alkyl group, r1 represents 1 to 1000, r2 represents 40 to 4995, r3 represents 0 to 4000, and n represents 1, 2, or 3.) 【Chemistry 2】 (In formula (Ib), R represents a hydrocarbon group having a carbonyl and an amine, r1 represents 1 to 1000, r2 represents 40 to 4995, and r3 represents 0 to 4000.)

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