JPH01230361A - Blood platelet preservation bag - Google Patents

Abstract

PURPOSE:To let blood platelets scarcely adhere on the inner surface of a bag, and thereby let the blood platelets in the bag be almost completely discharged out by letting two sheets of a bag be composed of polymer containing poly (ethylenebutylene) polystylene block mixed polymer, letting them, the inner surfaces of which are coarse, be piled up so as to be formed into the bag with the periphery sections of the sheets thermally welded. CONSTITUTION:A blood platelet preservation bag is composed of polymer containing poly (ethylenebatylene) polystylene block mixed polymer wherein two sheets forming a bag, the inner surfaces of which are coarse, are piled up in such a way that the periphery sections of the sheets are thermally welded. Since the bag is formed so that the periphery sections of the sheets are sealed, the sheets can be made thin and uniform in thickness so as to enable the bag to be available, which is excellent in gas permeability, flexibility and transparency. in addition, since the inner surfaces of the bag are made coarse, each of the inner surfaces will never be stuck together at the time of sterization, and blood platelets at the both end sections of the bag will never be delayed either in coming out later than those at the center section while eliminating difficulties in making sure of remaining blood platelets in the bag. The blood platelets in the bag can thereby be almost completely discharged out.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a platelet storage bag, and more specifically, the present invention relates to a platelet storage bag, and more specifically, the platelet storage bag has almost no adhesion of platelets to the inner surface of the bag, and the platelets inside the bag are almost completely stored. The present invention relates to a bag for storing platelets that can be stored for a long time and can be discharged immediately.

[Conventional technology]

Conventionally, polyvinyl chloride bags containing plasticizers such as dioctyl phthalate have been known as temporary storage bags for safely storing collected platelets for a long period of time and supplying them when needed. Gas permeability was low, platelets tended to stick to the bag surface, and platelet aggregation ability decreased when platelets were supplied. In addition, the bag showed blocking properties during high-pressure steam sterilization, and the inner surfaces of the bag were in close contact with each other, making it difficult to supply platelets into the bag.

Furthermore, this bag contains a plasticizer in the polyvinyl chloride, so if platelets are stored in the bag for a long period of time, the plasticizer will migrate into the platelets, impairing platelet functions such as the ability to recover from hypoosmotic shock. It had the disadvantage of lowering the

As a plastic composition for blood bags that improves these drawbacks, a bag made of a polymer composition in which poly(ethylene butylene) polystyrene block copolymer is mixed with polypropylene and ethylene vinyl acetate copolymer (or polyethylene) has been proposed. Is there (Special Public Service 1986-19461)
Publication No.).

This bag is made by blow molding, so
When the blood is drained, the inner surface of the bag, which has become hollow due to the blood being drained, does not come into close contact with the inner surface of the bag, resulting in blood remaining inside the bag. In particular, in platelet storage bags, it is not possible to pressurize air into the bag and then expel it, so platelets form a bag, so the film thickness is large and uneven, so the bag The drawback is that the performance required for platelet storage bags, such as gas permeability and transparency, is not uniform.

[Problems to be Solved by the Invention] As a result of intensive studies to improve the drawbacks of these conventional techniques, the present inventor has developed a sheet made of a polymer containing a poly(ethylene butylene) polystyrene block copolymer.
By stacking the bags together and making the inner surface of the bag heat-sealed, the inner surface of the bag is roughened, so platelets hardly stick to the inner surface of the bag, and the platelets inside the bag can be almost completely discharged. The inventors have discovered that a bag with excellent gas permeability and flexibility can be obtained, and have arrived at the present invention.

[Means to solve the problem]

That is, the present invention relates to a medical bag made of a polymer containing a poly(ethylene butylene) polystyrene block copolymer, in which two sheets having rough inner surfaces are overlapped and the peripheral portions are heat welded. This is a platelet storage bag formed by

[Function and Examples]

The present invention uses a polymer containing a poly(ethylene butylene) polystyrene block copolymer as a bag material, so that the plasticizer migrates into platelets and reduces platelet function, as in polyvinyl chloride bags. There are no shortcomings. Furthermore, since this resin has excellent gas permeability, platelets can be stored in the bag for a long time. In particular, bags made from a polymer alloy made by mixing poly(ethylene butylene) polystyrene block copolymer with polypropylene and ethylene acrylate copolymer are less deformed at high temperatures or low humidity, making them suitable for autoclaving and cryopreservation. is also optimal. Since the bag of the present invention is formed by sealing the periphery of two sheets, it is possible to form a thin sheet with a uniform film thickness, resulting in a bag with excellent gas permeability, flexibility, and transparency. Obtainable. In addition, since the inside surface of the bag is roughened, there is no problem that the inside surfaces of the bag will stick to each other during sterilization, and platelets at both ends of the bag will be discharged later than the center, making it difficult to check the amount of platelets remaining in the bag. . And it is possible to almost completely discharge the platelets in the bag.

The poly(ethylene butylene) polystyrene block copolymer used in the present invention has a structure in which the hard segment is polystyrene or a copolymer thereof, and the soft segment is a polyethylene butylene copolymer. The molecular weight of polystyrene or its copolymer used as the hard segment is s, oo.

~120,000. In addition, polyethylene butylene copolymer, which is a soft segment, has molecules it o, o o
.

~250,000 polybutadiene can be obtained by making a block copolymer with polystyrene constituting the hard segment and then hydrogenating the block copolymer. When the proportion of the soft segment in the block copolymer is 60 to 90% by weight, mechanical properties are improved.
Excellent flexibility can be obtained.

Polymers containing this poly(ethylene butylene) polystyrene block copolymer include a mixture of this block copolymer with polypropylene, and a polymer mixture of this block copolymer and polypropylene with polyethylene and ethylene propylene copolymers. , ethylene vinyl acetate copolymer, ethylene acrylic acid ester copolymer, etc., and especially poly(ethylene butylene)
A polymer mixture in which a polystyrene block copolymer, polypropylene, and ethylene acrylic acid ester copolymer are mixed at a specific blending ratio is preferable because it forms a polymer alloy and the physical properties of the bag do not change much at high or low temperatures.

Next, in the present invention, polypropylene is polypropylene alone or a copolymer mainly composed of polypropylene. Copolymer components include ethylene, butene-1, etc., and the proportion is 10
% by weight or less. Polypropylene has the ability to improve the strength when molded into a bag, and the strength can be significantly improved by mixing it with other polymers in a specific ratio to form a polymer alloy.

The mixing ratio of the polymer mixture of poly(ethylene butylene) polystyrene block copolymer and polypropylene is 10 to 55% by weight of block copolymer and 45 to 9% by weight of polypropylene.
It is 0% by weight. In addition, when using ethylene propylene copolymer (ethylene content 40% by weight or more) or ethylene vinyl acetate copolymer (ethylene content 35% by weight or more) as a third component in this polymer, block copolymer 4
5-ssii%, polypropylene 10-40% by weight, and third component 1-40% by weight are preferred.

When an ethylene acrylic acid ester copolymer is used as the third component, the block copolymer has a weight of 25 to 60%,
A mixing ratio of 20 to 40% by weight of polypropylene and 5 to 35% by weight of ethylene acrylic acid ester copolymer is preferable, and the polymer mixture mixed in this ratio has at least a portion in which the polystyrene segments of the block copolymer are crystallized and aligned. It is preferable to have two or more polymers, since the molecular chains of each polymer form a polymer alloy in which the molecular chains of each polymer are entangled in a network.

The ethylene acrylic ester copolymer used here acts as a compatibilizer for the block copolymer and polypropylene and contributes to the formation of a polymer alloy, but the acrylic ester used here is methyl acrylate,
Examples include ethyl acrylate and butyl acrylate, and their proportion in the copolymer component is 5 mol% or more.

The ethylene acrylic ester copolymer accounts for 5 to 35% by weight in the polymer mixture, but if it is less than 5% by weight, the polymer tends to have poor dispersion, poor extrusion processability, poor transparency, and especially poor low-temperature properties. If it exceeds 35% by weight, mechanical strength tends to decrease.

Bags are manufactured by putting these polymers into a blender, mixing them uniformly, melting the polymer mixture, extruding it into a sheet, and heat-welding the periphery. At that time, the melt-extruded sheet is cooled with an embossing roll to roughen the sheet surface. Then, the roughened surface of the sheet is brought inside the bag and the periphery of the bag is thermally welded to form a bag. It is preferable that the film thickness of the sheet is 100 to 400 microns because a bag with good flexibility and gas permeability can be obtained.

The roughening of the sheet may be applied to one or both sides of the bag, but the thickness of the roughened surface formed on the inner surface of the bag should be 5 to 100 mm.
Microns are preferred. If the size of the rough surface exceeds 100 microns, the transparency of the sheet will be poor and platelets will tend to remain in the recesses of the rough surface. tends to block.

The present invention will be explained below with reference to Examples.

Example 1 Poly(ethylene butylene) polystyrene block copolymer (Krayton G-165o manufactured by Shell Chemical Co., Ltd.) 60% by weight, polypropylene (FL6711N manufactured by Sumitomo Chemical Co., Ltd.)
35 [ii%, ethylene ethyl acrylate) [i combination (
Ethyl acrylate) J115 mol% D manufactured by Nippon Unicar Co., Ltd.
PDJ 6182) 5% by weight was mixed with a mixer,
It was melted at 200° C., extruded in sheet form onto an embossing roll at 25° C., and cooled to produce a sheet with a thickness of 250 μm and roughened on both sides (size of rough surface: 30 μm). These two sheets are stacked one on top of the other, and two membrane tube boats and a tube connected to a blood collection tube are sandwiched between them, as shown in Figure 1, and then heated into a bag shape using a heat sealing machine.
- In addition to sealing and fusing, the boat part and tube were also sealed to produce a bag with a capacity of 1,150 cm. In FIG. 1, 1 is the bag body, 2 and 3 are a pair of reaches [], 2 is a protective cover, and 3 is a membrane tube. 4 and 6
5 is a connecting tube, 5 is a connector, 7 is a blood collection tube, 8 is a plastic needle, 9 is a protector, and 10 is a hole for suspension. Platelets are collected from a plastic needle 8, passed through a blood collection tube 7, and stored in the bag body 1. In the drawing, there are only three boat parts, but four or more boat parts can be formed. The performance of this bag is shown in Table 1.

Comparative Example 1 The polymer mixture used in Example 1 was melted and extruded at 200°C, and a minimum film thickness of 25% was obtained using an inflation film forming machine.
A 0 micron, 150-capacity bag was manufactured. The performance of this bag is shown in Table 1.

The measurement items in the table were measured using the following method.

(1) Light transmittance (9)) Samples of 96' x 45 tea were cut from 10 locations on the bag, and the transmittance of 450+++ m was measured in a rice field.

(2) Thickness (microns) Measure the thickness of the bag in 10 places using a dial gauge.

(3) Residual liquid volume (rnl) A bag was filled with 150 - platelet concentrate, drained using a blood transfusion set at a head of 50 ctn, and the shortness at the end was measured.

(4) Blockability Judged by the peeling state of the sheet on the inner surface of the bag when the empty bag is sterilized in an autoclave at 12J°C for 20 minutes.○ Easily peeled off by hand.

Δ: Difficult to peel off easily by hand.

× Difficulty in peeling Table 1 As is clear from Table 1, the bag of the present invention has a more uniform film thickness than the comparative example bag, has a smaller amount of residual platelet fluid, and has a lower blocking property on the inner surface of the bag when sterilized in an autoclave. It is also excellent.

Example 2 60% by weight of the poly(ethylene butylene) polystyrene block copolymer used in Example 1 and 30% by weight of polypropylene were molded into ethylene vinyl acetate to produce a bag. Comparative Example 2 This polymer mixture was used as Comparative Example 1.
A bag was manufactured by blow molding in the same manner. The performance of these bags is shown in Table 2.

Example 3 A polymer mixture of 40% by weight of the poly(ethylene butylene) polystyrene block copolymer used in Example 1 and 20% by weight of polypropylene and 40% by weight of low density polyethylene was formed into a sheet in the same manner as in Example 1. It was molded and a bag was manufactured. Further, using this polymer mixture, a bag was molded by blow molding in the same manner as in Comparative Example 1. The performance of these bags is shown in Table 2.

Example 4 A polymer mixture of 60% by weight of the poly(ethylene butylene) polystyrene block copolymer used in Example 1 and 40% by weight of polypropylene was molded into a sheet in the same manner as in Example 1 to produce a bag. Further, using this polymer mixture, a bag was molded by blow molding in the same manner as in Comparative Example 1. The performance of these bags is shown in Table 2.

Table 2 As is clear from Table 2, the bag of the present invention has transparency, M'
? J is uniform, the amount of residual platelet fluid is small, and the pronogging properties of the sterilized Rona bag are excellent.

Examples 5-9 Poly(edilesibutylene) polystyrene block used in Example 1 Typical 6 K 40 weight it%, polypropylene 30ii%, ethylene ethyl acrylate copolymer 3
0% by weight was mixed in a mixer, melted at 200°C, extruded into sheets on various rough-surfaced rolls, and cooled to form films with various sizes shown in Table 3 on one side. p, Q,
A sheet of 2 s o microns was obtained. Two of these sheets were heat-sealed to the cedar of the bag using a heat-sealing machine with the rough side facing inside to obtain a bag with a capacity of 50 ml. The performance of this bag is shown in Table 3.

As is clear from Table 3, the bag of Example 8, which has a small rough surface on the inner surface of the bag, has the disadvantage of being prone to cracking during sterilization. Bag No. 9 has poor transparency and a large amount of platelet residual fluid.

〔Effect of the invention〕

The platelet storage bag of the present invention is a thin sheet with a uniform film thickness.
Because it is made of solid wood, it has excellent scum permeability, flexibility, and transparency. Furthermore, during sterilization, the inner surfaces of the bag do not clump together, and the platelets can be discharged horizontally without sticking to the inner surface of the bag, making it easy to check the remaining amount of platelets in the bag. have

Platelets can be almost completely discharged, and platelets can be stored for long periods of time without the need for plasticizers to migrate into platelets and reduce platelet function, unlike in polyvinyl chloride bags. The bag of the present invention is excellent and has almost all of the performances required for a platelet storage bag.

[Brief explanation of the drawing]

FIG. 1 shows platelet storage platelet ζ according to Example 1 of the present invention.
1 is a plan view of the bag, and in the figure, 1 is the bag body, 2 is a protective cover, 3 is a blower, and 7 is a blood collection tube.

Claims (2)

[Claims] (1) A medical bag made of a polymer containing poly(ethylene butylene) polystyrene block copolymer is formed by overlapping two sheets with rough inner surfaces and thermally welding the peripheral parts. A bag for platelet storage that is characterized by the following: (2) Polymer containing poly(ethylene butylene) polystyrene block copolymer is poly(ethylene butylene)
Consisting of a polymer composition consisting of a polystyrene block copolymer, polypropylene and ethylene acrylic acid ester copolymer, it has at least two or more portions in which the polystyrene segments of the poly(ethylene butylene) polystyrene block copolymer are crystallized and aligned. 2. The platelet storage bag according to claim 1, wherein the bag is a polymer alloy in which the molecular chains of the polymer are entangled in a network.