JP7395348B2 - Evaluation test method for body cavity fluid concentrator - Google Patents

Description

The present invention belongs to the field of medical devices, and relates to a method for evaluating and testing medical devices, and in particular, to a method for evaluating and testing devices or components for treating human body cavity fluid.

As a treatment for refractory ascites, ascites is removed from the patient, pathogenic substances such as bacteria and cancer cells are removed from the ascites, and the water is removed while leaving useful components such as albumin. There is a cell-free and concentrated ascites reinfusion therapy method in which the concentrated fluid is returned to the body.

Patients with ascites accumulation can be broadly divided into patients with hepatic ascites, whose accumulation is caused by diseases such as liver cirrhosis, and patients with cancerous ascites, whose accumulation is caused by cancers such as stomach cancer, ovarian cancer, and colorectal cancer. Traditionally, the above treatment methods were mostly performed on patients with hepatic ascites, but in recent years, the therapeutic effects of implementing the above treatment methods on patients with cancerous ascites have been recognized. There is an increase in the number of patients undergoing cancerous ascites.

In the above treatment method, an ascites treatment device is generally used. This ascites treatment device uses an ascites bag, a filter, a concentrator, and a concentrated ascites bag connected in series in this order, and filters and concentrates the ascites by flowing it through a head or a pump. ing.

For example, in patients with liver cirrhosis who tend to accumulate ascites or pleural effusion (hereinafter collectively referred to as ascites), in order to increase the patient's blood protein concentration by using the protein in the ascites, a needle is inserted into the accumulation area and externally removed. Ascites is filtered and concentrated using two types of filters, such as hollow fiber membranes, to obtain a concentrated protein solution, which is then instilled into the patient. The first of the two types of filters is a filtration filter that removes cellular components such as cancer cells and blood cell components contained in ascites, and does not allow cellular components to pass through, but allows solute components such as water and protein to pass through. A membrane having such a pore size is used. On the other hand, the other filter is a concentrating filter that removes water from ascites, which has a dilute protein concentration, and concentrates the protein.It uses a membrane that allows almost no protein components to pass through, but allows moisture, electrolytes, etc. to pass through. Generally, from the viewpoint of convenience, a method is used in which ascites is filtered to remove cellular components using a filter and then concentrated using a concentrator, and an apparatus that performs these processes continuously is used.

Further, as such an ascites treatment device, Patent Document 1 describes an ascites treatment device having a system that automates switching between filtration processing and recirculation processing.

Japanese Patent Application Publication No. 2013-188427

Various practical devices and devices have been announced for processing body cavity fluids, and these devices and devices are required to have extremely high safety and reliability in actual use. As mentioned above, concentrators are used to concentrate nutritional components useful for the human body in body cavity fluid, and it is generally thought that virus components and excess water have been removed from body cavity fluid after concentration. The expectation is always to return it directly to the human body as soon as possible.

When actually concentrating ascites using a concentrator, the concentrator is usually controlled using various control means of devices and devices. However, the present inventors found the following.

First, data on the structure or main parts of the device or device itself can be helpful as a reference regarding concentration capacity and effectiveness, but in actual operation, it may be difficult to adjust the concentrator to the appropriate parameters. This may also cause problems with operational stability.

During use, the concentrator is adjusted by various control means to achieve the desired effect, but the material of the concentrator itself (usually a porous membrane material with a predetermined pore size) also controls the concentration of body cavity fluid. has an important influence on effectiveness. On the other hand, the present inventors have previously determined the selection of this material only based on the parameters provided by the membrane material manufacturer; It was found that it was obtained by a standard test). Typically, once the membrane materials have been selected, it is implicit that these membrane materials themselves are acceptable for the treatment of human body cavity fluids. Therefore, improving the safety and reliability of concentrator use is primarily achieved by adjusting the operating conditions/parameters of the concentrator or by adjusting the structure of the concentrator, as described above.

Furthermore, in actual use, the concentrator may have various complex situations. For example, even if a concentrator is approved as having passed the test, it may be difficult to achieve a reliable concentration effect during concentration, resulting in prolonged concentration time and unnecessary loss of nutrients for the human body. In addition, when treating ascites, the body cavity fluid that is treated using a concentrator is usually the body cavity fluid that has been filtered by an upstream filter, so depending on the cause of the formation, for example, whether it is due to liver cirrhosis or cancer, The composition of the body cavity fluid is different and may vary depending on the upstream filter and its filtration conditions. Therefore, even if a concentrator achieves the desired treatment effect when treating a particular patient or when used in conjunction with a particular upstream filter, problems may arise during use when the patient or upstream filter changes. This may occur, and the applicability of the concentrator is questioned. Therefore, a test method for evaluating the applicability of concentrators is desperately needed.

Since the body cavity fluid processing device including the concentrator is a closed one-to-one system, abnormalities may occur in the body cavity fluid processing by the concentrator (for example, the concentration capacity may be abnormally reduced due to clogging of the concentrator). Therefore, it is usually not possible to adjust or repair the equipment using simple operations. Since there is usually no effective solution, it is usually necessary to replace the concentrator and even the upstream filter, the economic costs and actual losses of which are not easily accepted. Moreover, since there is no effective solution, such problems are generally recognized as unavoidable systemic risks.

Regarding the above-mentioned problem, the present inventors believe that determining the performance of a concentrator based on experience of isolated material parameters, control means, device configuration, etc. is a cause of the above-mentioned systematic risk. I guessed it. Further consideration revealed that such systemic risks are not inevitable. The problem to be solved by the present invention is to provide an overall and systematic evaluation method that can effectively evaluate the effectiveness of using a body cavity fluid concentrator.

As a result of intensive studies, the present inventors have found that the above problems can be solved by implementing the following invention.

The present invention
a concentration step of sending a test solution containing protein to a body cavity fluid concentrator and separating it into a concentrated solution and a filtrate;
a calculation step of measuring the components in the test liquid and the components in the concentrate and/or the filtrate and calculating the protein recovery performance of the body cavity fluid concentrator;
Provided is an evaluation test method for a body cavity fluid concentrator including:

In some embodiments, the number of blood cells in the test solution is 1×10 ² cells/μL or less.

In some embodiments, the test solution has a total protein concentration of 0.5-2.4 g/dL.

In some embodiments, the test solution has a total protein concentration of 0.5-0.9 g/dL.

In some embodiments, the test solution has a total protein concentration of 2.0-2.4 g/dL.

In some embodiments, the test solution has an albumin to globulin ratio (A/G ratio) of 0.8 to 1.5.

In some embodiments, the body cavity fluid concentrator includes a porous membrane, an input port communicating with the primary side of the porous membrane, a first output port communicating with the primary side of the porous membrane, and a first output port communicating with the primary side of the porous membrane. a second output port communicating with the secondary side;
The concentration step includes:
The test liquid is sent to the input port, and the concentrated liquid is collected from the first output port.

In some embodiments, the protein is at least one of albumin and α1-MG.

In some embodiments, the protein recovery performance is albumin recovery.

In some embodiments, the albumin recovery rate is represented by formula (1).
Formula (1)... Albumin recovery rate (%) = (Amount of albumin in concentrated solution/Amount of albumin in test solution) x 100

In some embodiments, the albumin recovery rate is represented by formula (2).
Formula (2)...Albumin recovery rate (%) = {(concentrated liquid amount x albumin concentration in the concentrated liquid)/(test liquid amount x albumin concentration in the test liquid)} x 100

In some embodiments, the method further includes a residual liquid recovery step of recovering residual test liquid remaining in the body cavity fluid concentrator after the concentration step.

In some embodiments, the protein recovery performance is an albumin recovery rate, and the calculation step includes measuring albumin in the test liquid, the concentrated liquid, and the residual test liquid, and calculating the protein recovery performance of the body cavity fluid concentrator. Calculate.

In some embodiments, the albumin recovery rate is represented by formula (3).
Formula (3)... Albumin recovery rate (%) = {(Amount of albumin in concentrated solution + Amount of albumin in residual test solution)/Amount of albumin in test solution} x 100

In some embodiments, the albumin recovery rate is represented by formula (4).
Formula (4)... Albumin recovery rate (%) = {(concentrated liquid amount x albumin concentration in the concentrated liquid + residual test liquid amount x albumin concentration in the residual test liquid) / (test liquid amount x albumin concentration in the test liquid) Albumin concentration)}×100

In some embodiments, the method further includes a filtrate collection step of collecting the filtrate after the concentration step.

In some embodiments, the protein recovery performance is albumin permeability, and the calculating step measures albumin in the test liquid and the filtrate, and calculates the albumin permeability.

In some embodiments, the albumin permeability is expressed by formula (5).
Formula (5)...Albumin transmittance (%) = (Amount of albumin in filtrate/Amount of albumin in test liquid) x 100

In some embodiments, the albumin permeability is expressed by equation (6).
Formula (6)... Albumin transmittance (%) = {(filtrate amount x albumin concentration in filtrate)/(test liquid amount x albumin concentration in test liquid)} x 100

In some embodiments, the protein recovery performance is α1-MG recovery rate or α1-MG permeability.

In some embodiments, the calculation step measures α1-MG in the test liquid and the concentrate, and calculates the α1-MG recovery rate of the concentrator.

In some embodiments, the α1-MG recovery rate is expressed by formula (7).
Formula (7)... α1-MG recovery rate (%) = (α1-MG amount in concentrated solution / α1-MG amount in test solution) × 100

In some embodiments, the α1-MG recovery rate is expressed by formula (8).
Formula (8)... α1-MG recovery rate (%) = {(concentrated liquid amount x α1-MG amount in the concentrated liquid)/(test liquid amount x α1-MG amount in the test liquid)} x 100

In some embodiments, the method further includes a residual liquid recovery step of recovering residual test liquid remaining in the body cavity fluid concentrator after the concentration step.

In some embodiments, the calculation step measures α1-MG in the test liquid, the concentrated liquid, and the residual test liquid, and calculates the α1-MG recovery rate of the concentrator.

In some embodiments, the α1-MG recovery rate is expressed by formula (9).
Formula (9)...α1-MG recovery rate (%) = {(α1-MG amount in concentrated solution + α1-MG amount in residual test solution)/α1-MG amount in test solution}×100

In some embodiments, the α1-MG recovery rate is expressed by equation (10).
Formula (10)... α1-MG recovery rate (%) = {(concentrated liquid amount x α1-MG concentration in concentrated liquid + residual test liquid amount x α1-MG concentration in residual test liquid) / (test liquid Amount x α1-MG concentration in test solution)} x 100

In some embodiments, the method further includes a filtrate collection step of collecting the filtrate after the concentration step.

In some embodiments, the protein recovery performance is α1-MG permeability, and the calculating step measures α1-MG in the test liquid and the filtrate, and calculates the α1-MG permeability.

In some embodiments, the α1-MG transmittance is expressed by equation (11).
Formula (11)...α1-MG transmittance (%) = (α1-MG amount in filtrate/α1-MG amount in test liquid) x 100

In some embodiments, the α1-MG transmittance is expressed by equation (12).
Formula (12)... α1-MG transmittance (%) = {(filtrate amount x α1-MG concentration in filtrate)/(test liquid amount x α1-MG concentration in test liquid)} x 100

The present invention provides an evaluation test method for a body cavity fluid concentrator, and by implementing the above invention, the following effects can be achieved.
(1) The test method for body cavity fluid concentrators according to the present invention is the first evaluation test method for concentrators, and is a comprehensive and systematic evaluation method. Such a method has not been reported in any literature known in the art and can provide a reliable evaluation test method for concentrators used in the art.
(2) The evaluation test method for a body cavity fluid concentrator according to the present invention can accurately reflect the processing effect and processing capacity of the concentrator when concentrating human body cavity fluid, and the concentrator of this type and lot can provide medical services to patients. Since it is possible to evaluate whether the concentrator can provide reliably and safely, it is possible to prevent variations and accidents during use of the concentrator as much as possible, and reduce the medical burden on patients and medical risks.
(3) The evaluation test method for body cavity fluid concentrators according to the present invention can be widely applied, that is, it can be applied not only to the evaluation of ascites concentrators caused by liver cirrhosis, but also to the evaluation of ascites concentrators caused by cancer. can.
(4) The evaluation test method for body cavity fluid concentrators according to the present invention has convenient operability and enables rapid testing of concentrators.

It shows the structure of a concentrator in one embodiment of the present invention. 1 shows an apparatus used for an evaluation test in an embodiment of the present invention. It is a TMP data graph during operation of each concentrator in an example and a reference example of the present invention.

The present invention will be explained in detail below. The explanation of technical matters described below is based on typical embodiments and specific examples of the present invention, but the present invention is not limited to these embodiments and specific examples. In addition, the following will be explained.
In this specification, the numerical range represented by "numerical value A to numerical value B" includes numerical values A and B at the end points.
As used herein, "%" means weight or mass percentage unless otherwise specified.
As used herein, "may" means that the treatment may or may not be performed.
As used herein, "optional" or "optional" refers to the use or non-use of the substance, component, process, condition, etc.
In this specification, all unit names are international standard unit names.
In this specification, unless otherwise specified, "plurality" means two or more.
As used herein, "some (preferred) embodiments,""another (preferred) embodiment,""embodiment," etc. refer to specific elements (e.g., requirements, structure, a property and/or characteristic) is included in at least one embodiment described herein and may be present or absent in other embodiments. Further, the above elements can be combined in any suitable manner in each embodiment.

The present invention provides an evaluation test method for a body cavity fluid concentrator, which includes a concentration step and a calculation step.
In the concentration step, the test liquid containing protein is sent to a body cavity fluid concentrator and separated into a concentrated liquid and a filtrate. In the calculation step, components in the test liquid and components in the concentrated liquid and/or the filtrate are measured, and the protein recovery performance of the body cavity fluid concentrator is calculated.

<Body cavity fluid concentrator>
The body cavity fluid concentrator (sometimes simply referred to as a "concentrator") applied to the present invention may be any concentrator for body cavity fluid concentration in the art.

FIG. 1 shows a typical structure of a concentrator to which the present invention is applied. In the figure, 1 is the concentrator main body, and 3 is the input port of the concentrator. When actually treating a patient, body cavity fluid processed by an upstream filter (not shown) enters the concentrator main body 1 from the input port 3 of the concentrator. Accordingly, when implementing the evaluation method of the present invention, the test liquid used in the evaluation method enters the concentrator 1 from the input port 3. In FIG. 1, 2 is a concentrate output port (first output port) of the concentrator, and during actual use, the concentrate processed by the concentrator is taken out from the concentrate output port 2. In FIG. 1, 4 is a filtrate output port (second output port) for taking out the filtrate produced during concentration in the concentrator.

Furthermore, in another embodiment, the concentrator applied to the present invention also includes a residual fluid discharge port (not shown) for discharging body cavity fluid remaining in the concentrator main body 1.

A concentrating unit is provided within the concentrator body 1. In some embodiments of the invention, the concentration unit is selected from porous membranes. The porous membrane is not particularly limited, and common ultrafiltration membranes in the industry can be used. Typically, the pore size of the porous membrane of the concentrator is smaller than the pore size of the membrane used in the upstream filter. Porous membranes mainly concentrate proteins in low-concentration protein solutions. Also, the filtrate, which is mainly water from which most of the protein has been removed, escapes to the other side of the membrane.

In some preferred embodiments of the present invention, in the porous membrane applied to the present invention, the ratio of the number of pores of 0.08 μm to 0.12 μm to the total number of pores is 60%, preferably 70% or more. It has a pore size distribution. In another preferred embodiment, the ultrafiltration performance of the concentrator applied to the present invention is 85 mL/min/200 mmHg or more and 150 mL/min/200 mmHg or less. If the ultrafiltration performance is lower than 85 mL/min/200 mmHg, the amount of filtrate discharged during concentration will be small, making it impossible to obtain a sufficiently concentrated protein solution. It is preferable that the ultrafiltration performance is 85 mL/min/200 mmHg or higher because the possibility of clogging is reduced, and more preferably 95 mL/min/200 mmHg or higher. On the other hand, if the ultrafiltration performance is higher than 150 mL/min/200 mmHg, protein will leak into the filtrate, making it impossible to obtain a sufficient protein concentration.

Although the type of porous membrane is not particularly limited, in some preferred embodiments, hollow fiber membranes are used from the viewpoint of concentration efficiency. The shape and dimensions of the hollow fiber membrane referred to here are not particularly limited, as long as it has the above-mentioned ultrafiltration performance. As for the material, polysulfone is preferable because it is easy to control the pore size during membrane formation and has excellent chemical stability. Alternatively, a sulfone type including polyether sulfone or a cellulose type may be used. Since polysulfone polymers are aromatic compounds, they have particularly excellent radiation resistance, are also very resistant to heat and chemical treatments, and are excellent in safety. Therefore, various membrane forming conditions can be adopted, and radiation sterilization is also possible, making it particularly preferable as a membrane material for use in ascites concentrators. Note that "-based" means not only homopolymers but also copolymers with other monomers and chemically modified analogs.

The polysulfone polymer (hereinafter sometimes referred to as PSf) referred to herein is a general term for polymer compounds having sulfone bonds, and is not particularly defined, but for example, the repeating unit may have the following formula (1 ), formula (2), formula (3), formula (4) and formula (5). It may be a modified polymer in which substituents are introduced into some of these aromatic rings. From the viewpoint of industrial availability, aromatic polysulfone polymers whose repeating units are represented by formulas (1), (2), and (3) are preferred, and among them, polysulfones having the chemical structure represented by formula (1) are preferred. Particularly preferred. This bisphenol type polysulfone resin is commercially available, for example, from Solvay Advanced Polymers under the trade name "Udel (registered trademark)", and there are several types depending on the degree of polymerization, etc., but there are no particular limitations.

The polysulfone hollow fiber membrane in the present invention is preferably made hydrophilic by a hydrophilic polymer. This is because polysulfone-based polymers alone make the surface of the hollow fiber membrane hydrophobic, and proteins are likely to be adsorbed to such a surface, causing a decrease in protein recovery performance. Examples of the hydrophilic polymer include polyvinylpyrrolidone (hereinafter sometimes referred to as PVP), polyethylene glycol, polyvinyl alcohol, polypropylene glycol, etc. Among them, PVP is preferable in terms of its hydrophilic effect and safety. There are several types of PVP depending on the molecular weight, etc., and for example, commercially available products include PVP K-15, 30, and 90 (all manufactured by ISP). The molecular weight (viscosity average molecular weight) of PVP used in the present invention is 10,000 to 2,000,000, preferably 50,000 to 1,500,000. The content of the hydrophilic polymer in the membrane is 3 to 20%, preferably 3 to 10% of the total amount of the polymer. If the content is less than 3%, the effect as a hydrophilic agent will be diminished, and if the content exceeds 20%, the viscosity of the film-forming stock solution will increase too much, which is not preferable in terms of production.

The hydrophilized polysulfone hollow fiber membrane can be produced using a known wet-dry membrane forming technique. First, a homogeneous spinning stock solution is prepared by dissolving a polysulfone polymer and a hydrophilic polymer such as polyvinylpyrrolidone in a common solvent for both. When the hydrophilic polymer is polyvinylpyrrolidone, such common solvents include, for example, dimethylacetamide (hereinafter referred to as DMAC), dimethylsulfoxide, N-methyl-2-pyrrolidone, dimethylformamide, sulfolane, dioxane, etc. or a mixture of two or more of the above solvents. Note that in order to control the pore size, additives such as water may be added to the spinning dope.

The spinning dope from the orifice of the spinneret and the hollow liquid from the tube are simultaneously discharged into the air. The hollow inner liquid is for coagulating the spinning stock solution, and water or a coagulating liquid mainly composed of water can be used. The composition of the hollow inner solution can be determined depending on the performance of the hollow fiber membrane, such as its ultrafiltration performance, and cannot be determined unconditionally, but it is generally the solvent used in the spinning dope. A mixed solution of and water is preferably used. For example, a 0 to 65% by weight DMAC aqueous solution is used as the hollow internal liquid. The spinning stock solution discharged from the spinneret together with the hollow inner liquid travels through the idle running section, and is introduced into and immersed in a water-based coagulation bath installed at the bottom of the spinneret to complete coagulation. Thereafter, the coagulated hollow fibers undergo a washing process, etc., and then the wet hollow fiber membranes are wound up with a winder to obtain a bundle of hollow fiber membranes, which is then dried. Alternatively, a hollow fiber bundle may be obtained by performing a washing step and then drying in a dryer, and the manufacturing method is not specified.

Since the concentrator operates based on pressure, for convenience of explanation, the side of the porous membrane in the concentrator where the pressure is higher is referred to as the primary side of the porous membrane, and the side where the pressure is lower is referred to as the secondary side of the porous membrane.

Here, for example, protein components are concentrated on the primary side, and filtrate (moisture) is discharged on the secondary side. In FIG. 1, the concentrate output port 2 of the concentrator is connected to the space on the primary side of the porous membrane, and the filtrate output port 4 is connected to the space on the secondary side of the porous membrane.

<Evaluation method>
The present invention evaluates the above concentrator using at least a concentration process and a calculation process.
In the so-called concentration step, a suitable test liquid is fed into the concentrator via the concentrator input port 3 through a circuit, and the test liquid is separated into a concentrate and a filtrate by means of a porous membrane.

(Test liquid)
The present invention tests the concentration and separation capabilities of a concentrator by providing a test liquid. Theoretically, it is most reliable to conduct evaluations and tests using patient body cavity fluids to fully reflect the actual concentration and separation capabilities of the test concentrator. However, such a theory is not realistic.

First, it is nearly impossible to obtain a patient's body cavity fluid in advance, and it is even more impossible to obtain body cavity fluid that has been filtered by standard methods. When a concentrator is evaluated using a specific patient's body cavity fluid, the evaluation results are not universal and relate only to that individual patient at a specific time. Furthermore, since the concentrators themselves are usually expensive, and the concentrators after testing are essentially non-reusable, each patient would have to pay at least twice as much in medical costs if done in this way. Become. Furthermore, once the patient's body cavity fluid is used in the test, it cannot be recovered, so it is also impossible from a medical ethics perspective. Therefore, evaluating the concentration performance of a concentrator using a patient's body cavity fluid has no practical value.

Thus, it is important to provide reliable test liquids for the evaluation of concentrators. The present inventors evaluated the concentration performance of the concentrator by providing a test solution containing protein at a predetermined concentration, since the most important function of the concentrator is the concentration and recovery of body fluids containing proteins. I found out that it is possible. Furthermore, since the composition of human body cavity fluid differs depending on the cause of its formation, the composition of body cavity fluid from an upstream filter supplied to the concentrator during actual processing does not remain constant. Therefore, selection of a test solution with an appropriate concentration is also important.

In the present invention, from the viewpoint of increasing the versatility and reliability of the evaluation method, a solution having a protein content of 0.5 g/dL or more and 2.4 g/dL or less, particularly an aqueous solution, is used as the test liquid. If the protein concentration is too low, the effect of concentration cannot be evaluated (if the protein is too dilute, the concentrator will actually concentrate water, and the results of the evaluation test will not reflect the actual treatment effect of the concentrator on human body cavity fluid. cannot be reflected). On the other hand, by setting the protein content to 2.4 g/dL or less, TMP (the membrane that covers the porous membrane in the concentrator) is (pressure difference) does not increase, and good reproducibility of evaluation tests can be ensured. Furthermore, in some preferred embodiments of the present invention, the number of blood cells in the test solution is 1×10 ² cells/μL or less. By setting the blood cell count within the above range, the present inventors are able to prevent a coagulation cascade (thrombus-like clot) from occurring in the test liquid and test the concentration performance with good reproducibility.

The present inventors have found that if the protein content in the test solution is set within the above range, the evaluation results will be even closer to the effects of actual use of the concentrator. In addition, by adjusting the protein content within the above range, the versatility of the evaluation method of the present invention can be increased, that is, the actual performance of the concentrator for human body cavity fluid caused by liver cirrhosis can be improved. In addition to being able to accurately evaluate, it is also possible to accurately evaluate the actual usage performance of concentrators that target human body cavity fluids caused by various cancers.

Furthermore, in some preferred embodiments of the present invention, the protein content in the test solution is in the range of 0.5 g/dL or more and 0.9 g/dL or less. Such a test liquid has higher reliability, especially when evaluating the actual performance of a concentrator for human body cavity fluid caused by liver cirrhosis.

In another preferred embodiment of the present invention, the protein content in the test solution is in the range of 2.0 g/dL or more and 2.4 g/dL or less. Such a test liquid has higher reliability, especially when evaluating the actual performance of a concentrator for human body cavity fluids caused by various cancers.

Furthermore, regarding the types of proteins, those containing albumin and proteins other than albumin can be used in the present invention. Preferably, the protein other than albumin is a globulin. Furthermore, from the viewpoint of reducing clogging of the concentrator due to components of the test solution, preferably a small amount of fibrin or no fibrin is used as the protein.

In some embodiments of the present invention, the ratio of albumin to globulin (A/G ratio) of the test liquid is 0.8 or more and 1.5 or less. In the present invention, it is believed that a test solution with a ratio of albumin and globulin within the above range leads to evaluation results that better reflect the performance of the concentrator during actual operation.

Furthermore, in some preferred embodiments of the present invention, the ratio of albumin to globulin (A/G ratio) of the test solution is 0.8 or more and 1.2 or less. Such a test liquid has higher reliability, especially when evaluating the actual performance of a concentrator for human body cavity fluid caused by liver cirrhosis.

Furthermore, in some preferred embodiments of the present invention, the ratio of albumin to globulin (A/G ratio) of the test solution is 0.9 or more and 1.5 or less. Such a test liquid has higher reliability, especially when evaluating the actual performance of a concentrator for human body cavity fluids caused by various cancers.

In addition, when actually using the test solution, it is expected that the test solution will not only have high reliability in evaluation tests, but also have uniformity and stability of the components from the viewpoint of ease of actual use and storage of the test solution. Ru. Therefore, in some preferred embodiments of the present invention, a predetermined content of Contain an anticoagulant.

The anticoagulant that can be used in the test solution in the present invention is not particularly limited, and at least one selected from the group consisting of heparin and its salts, ethylenediaminetetraacetate, citrate, oxalate, and hirudin, or these. A mixture of can be used.

In some preferred embodiments, the anticoagulant comprises at least heparin or a salt thereof. From the viewpoint of effectively increasing the stability of the test solution, the anticoagulant contains 2 units/mL or more, preferably 3 units/mL or more, more preferably 5 units/mL or more of heparin and/or its salt. .

The test solution for evaluation in the present invention may contain, in addition to the above-mentioned protein and an optional anticoagulant, other auxiliary components as required, as long as they do not affect the evaluation effect of the test solution. Auxiliary components include inorganic salts and pH buffering components.

(Method for manufacturing test liquid)
In the present invention, the method for producing the test liquid is not particularly limited. In some embodiments of the invention, the proteins described above can be dispersed in water to form a stable dispersion using dispersion methods common in the art.

In some preferred embodiments of the invention, the test solution can be prepared with non-human animal plasma. Since animal plasma contains proteins and is biologically similar to human body cavity fluid to some extent, the use of animal plasma not only simplifies the preparation of the test solution but also increases the effectiveness of the use of the test solution.

The above-mentioned animal plasma is not particularly limited, and the blood of (slightly large) mammals can be used, for example, the blood of cows, sheep, pigs, horses, and deer can be used. From the viewpoint of ease of collection, bovine or sheep plasma is preferably used. Further, the plasma may be fresh plasma or refrigerated plasma, but fresh animal plasma is preferably used from the viewpoint of ease of handling. Furthermore, if desired, the above-mentioned anticoagulants, particularly heparin, may be added to the plasma.

In some embodiments of the present invention, test solution preparation using animal plasma includes a filtration step of filtering the raw material solution through a filtration membrane having an average pore size of 0.2 μm or less.

The filtration membrane that can be used for the test liquid in the filtration step is not particularly limited, and in some embodiments, common porous membranes in the art, typically hollow fiber membranes, can be used.

A cylindrical container with a hollow fiber membrane bundle inside can be used. In the cylindrical container, a specific substance in the body cavity fluid is removed by passing the raw material liquid from the outside of the hollow fiber membranes of the hollow fiber membrane bundle to the inside of the hollow fiber membranes. Here, the hollow fiber membranes are arranged in a dispersed manner so that the filling rate of the hollow fiber membrane bundle is 20% or more and 41% or less in the internal cross section of the cylindrical container, and the hollow fiber membrane bundle has an average The distance between hollow fiber membranes is 150 μm or more.

In some preferred embodiments, the maximum distance between hollow fiber membranes in the hollow fiber membrane bundle is 300 μm or more, the effective membrane area of the hollow fiber membrane bundle is 0.7 m ² or more and 3.0 m ² or less, and the The inner diameter of the hollow fiber membrane is 50 μm or more and 500 μm or less.

Furthermore, in another embodiment, the filtration membrane used in the filtration step may be gauze, and the gauze may be used in a single layer or in a stacked manner.

From the viewpoint of filtration convenience and cost, the filtration step is preferably performed using the gauze described above. Use gauze to remove unnecessary components, mainly fibrin and blood cells. To ensure the effectiveness of filtration, filtration may be performed multiple times.

In some preferred embodiments, in order to prevent deterioration of the uniformity of test results due to components such as fibrin, fibrin may be removed by performing a step of freezing and thawing the raw material solution before the filtration step. . Note that this freezing/thawing step and fibrin removal step may be performed after the filtration step.

The filtrate obtained in the filtration step is further subjected to a concentration adjustment step so that it has the composition of the test solution described above.

The concentration adjustment step includes adjusting the protein concentration, and typically, the protein concentration is adjusted to a predetermined range of the test solution in the present invention by adding protein.

Furthermore, the test liquid obtained by the above-described process may be placed in a container for future use. Storage conditions for the test solution are not particularly limited, but typically it can be stored refrigerated.

From the viewpoint of convenience of use, in a preferred embodiment of the present invention, the test solution obtained in the above steps may be stored as a kit. The kit includes a storage section and a test liquid contained in the storage section. The kit may include a flexible or rigid housing and, in some embodiments, has an output port or connection that allows communication with the outside world. Such output ports or connections are sealed until use. In another embodiment, the kit may be evacuated, ie, there is a vacuum inside until the time of use.

(Evaluation process)
In the present invention, the concentrator is evaluated using the above test liquid.

<Concentration process>
The apparatus shown in FIG. 2 is an apparatus used in one embodiment of the present invention, in which 5 is a container (test liquid bag) containing a test liquid, and 6 is a container containing a concentrated liquid obtained by processing in a concentrator. In the container (concentrate bag), 7 is a container (filtrate bag) that accommodates the filtrate discharged from the concentrator.

Furthermore, in another embodiment, the system used for the evaluation test, in addition to the device or structure shown in FIG. 2, optionally includes a recirculation device for recycling the concentrate in the concentrate bag 6 to the test liquid bag. When the amount of the concentrate contained in the concentrate bag reaches a first predetermined amount, the filtration operation is stopped, and the concentrate contained in the concentrate bag 6 is transferred to the test liquid by the recirculation device. and a controller for recirculating the bag and feeding it back to the concentrator for concentration.

Furthermore, the material transport between each device in the present invention may be performed by a power device, and the type of the power device is not particularly limited, and a roller pump can be used.

The evaluation test of the present invention can be conducted under conditions of 0 to 50°C, preferably 15 to 35°C. If the temperature is too low, the fluidity of the test liquid will deteriorate and the concentration process of the concentrator will also deteriorate. If the temperature is too high, protein components may denature.

When conducting the evaluation test of the present invention, the test liquid is transported from circuit a to the concentrator main body 1, and by pressurizing the primary side of the porous membrane in the concentrator, the test liquid is concentrated and the filtrate (mainly water) is discharged. will be held. The concentrate is further fed to the concentrate bag 6 via circuit b, and the filtrate is fed to the filtrate bag 7 via circuit c.

Furthermore, the recirculation device allows the concentrate in the concentrate bag 6 to be returned to the test liquid bag 5 for reconcentration and re-discharge.

The components of the concentrate in the concentrate bag 6 and/or the filtrate in the filtrate bag 7 after the concentration process are measured to evaluate the performance of the concentrator.

<Calculation process>
In the present invention, the components of the test liquid, the concentrate and/or the filtrate are measured in the calculation step, and the protein recovery performance of the body cavity fluid concentrator is calculated.

In some embodiments, the protein recovery performance of the concentrator is evaluated by the albumin recovery rate of the concentrator.

The amount of albumin in the test solution and the amount of albumin in the concentrated solution are each measured using an automatic measuring device (BioMajesty ^TM JCA-BM6050 manufactured by JEOL Ltd.), and the albumin recovery rate is calculated using equation (1).
Formula (1)...Albumin recovery rate (%) = (Amount of albumin in concentrated solution/Amount of albumin in test solution) x 100

In another embodiment, the albumin recovery rate may be calculated using equation (2).
Formula (2)...Albumin recovery rate (%) = {(concentrated liquid amount x albumin concentration in the concentrated liquid)/(test liquid amount x albumin concentration in the test liquid)} x 100

Furthermore, in another embodiment, the concentrator evaluation method also takes into account the residual liquid remaining in the concentrator, especially if the concentrator has a large volume or has an obvious residual liquid.
In this case, the evaluation test method of the present invention further includes a residual liquid recovery step of recovering the residual test liquid remaining in the body cavity fluid concentrator after the concentration step.

Therefore, in some embodiments, the protein recovery performance is an albumin recovery rate, and in the calculation step, albumin in the test liquid, the concentrated liquid, and the residual test liquid is measured, and the protein recovery rate in the body cavity fluid concentrator is measured. Calculate recovery performance.
In this case, the albumin recovery rate is calculated using equation (3).
Formula (3)... Albumin recovery rate (%) = {(Amount of albumin in concentrated solution + Amount of albumin in residual test solution)/Amount of albumin in test solution} x 100

Furthermore, the albumin recovery rate may be calculated using equation (4).
Formula (4)... Albumin recovery rate (%) = {(concentrated liquid amount x albumin concentration in the concentrated liquid + residual test liquid amount x albumin concentration in the residual test liquid) / (test liquid amount x albumin concentration in the test liquid) Albumin concentration)}×100

In another embodiment of the invention, the filtrate is recovered after the concentration step. Since the filtrate may contain proteins that have passed through the porous membrane, in this case, the protein recovery performance can also be expressed by albumin permeability. That is, in the calculation step, albumin in the test liquid and the filtrate is measured, and the albumin permeability is calculated.

In some embodiments, the albumin permeability is calculated by, for example, equation (5).
Formula (5)...Albumin transmittance (%) = (Amount of albumin in filtrate/Amount of albumin in test liquid) x 100

In some embodiments, the albumin permeability may be calculated using equation (6), for example.
Formula (6)... Albumin transmittance (%) = {(filtrate amount x albumin concentration in filtrate)/(test liquid amount x albumin concentration in test liquid)} x 100

Furthermore, the actual usability of the concentrator may be evaluated based on the α1-MG recovery rate or α1-MG permeability in addition to the albumin concentration status.

In the calculation step, the α1-MG in the test liquid and the concentrated liquid are measured to calculate the α1-MG recovery rate of the concentrator.

In some embodiments, the α1-MG (α1-microglobulin) recovery rate is calculated using equation (7).
Formula (7)... α1-MG recovery rate (%) = (α1-MG amount in concentrated solution / α1-MG amount in test solution) × 100

In some embodiments, the α1-MG recovery rate may be calculated using equation (8), for example.
Formula (8)... α1-MG recovery rate (%) = {(concentrated liquid amount x α1-MG amount in the concentrated liquid)/(test liquid amount x α1-MG amount in the test liquid)} x 100

Furthermore, when the residual liquid is also considered, in the calculation step, α1-MG in the test liquid, the concentrated liquid, and the residual test liquid is measured, and the α1-MG recovery rate of the concentrator is calculated.
In some embodiments, the α1-MG recovery rate is calculated using equation (9).
Formula (9)...α1-MG recovery rate (%) = {(α1-MG amount in concentrated solution + α1-MG amount in residual test solution)/α1-MG amount in test solution}×100

In some embodiments, the α1-MG recovery rate is calculated using equation (10).
Formula (10)... α1-MG recovery rate (%) = {(concentrated liquid amount x α1-MG concentration in concentrated liquid + residual test liquid amount x α1-MG concentration in residual test liquid) / (test liquid Amount x α1-MG concentration in test solution)} x 100

Further, the protein recovery performance may be evaluated based on the transmittance of α1-MG. In this case, in the calculation step, α1-MG in the test liquid and the filtrate is measured, and the α1-MG transmittance is calculated.

In some embodiments, the α1-MG transmittance is calculated using equation (11).
Formula (11)...α1-MG transmittance (%) = (α1-MG amount in filtrate/α1-MG amount in test liquid) x 100

In some embodiments, the α1-MG transmittance may be calculated using equation (12).
Formula (12)... α1-MG transmittance (%) = {(filtrate amount x α1-MG concentration in filtrate)/(test liquid amount x α1-MG concentration in test liquid)} x 100

<Data processing>
In the present invention, the performance of the concentrator in actual use is evaluated based on the albumin recovery rate, albumin permeability, α1-MG recovery rate, or α1-MG permeability as described above.

In some embodiments, evaluation can be performed based on data calculated by any of the above equations (1) to (12). Further, if desired, a more comprehensive evaluation index may be obtained by weighting the data using a known mathematical method. A specific mathematical processing method is not particularly limited in the present invention.

The present invention will be explained below using specific examples.

Example Bovine plasma was filtered through a hollow fiber membrane having an average pore size of 0.2 μm or less, and the total protein (hereinafter referred to as “TP”) concentration was 2 g/dL, and the albumin/globulin ratio (“A/G ratio”) The solution adjusted to 1.2 was used as the test solution. The heparin concentration in the test solution is 3.2 units/mL, and the blood cell count is 0 cells/μL.

Put the test solution into a test solution bag (5 in Figure 2), adjust the temperature to 27 ± 1°C, and pass it through the circuit to the input port of the concentrator (5 in Figure 2) so that the concentration ratio is 10 times. 3) at a flow rate of 50 mL/min, the flow rate at the first output port (2 in Figure 2) of the concentrator was 5 mL/min (collected in a bag), and the concentrator The liquid was pumped for 60 minutes (test liquid volume: 3 L) so that a filtrate was generated (collected in a bag) at a flow rate of 45 mL/min from the second output port (4 in FIG. 2).

After the concentration was stopped, the recovery rate of albumin was calculated using equation (1) using the test solution and the concentrated solution. At this time, the amount of liquid remaining in the concentrator was 46 mL.
Albumin recovery rate (%) = (albumin amount in concentrated solution/albumin amount in test solution) x 100

As a result of measurement, the amount of albumin in the concentrate was 23.7 g. Furthermore, the albumin recovery rate was 69.3%.

Furthermore, air was introduced from the input port of the concentrator to collect the residual test liquid remaining in the concentrator. Using the test solution, concentrated solution, and residual test solution, the albumin recovery rate was calculated using equation (3).
Albumin recovery rate (%) = {(Amount of albumin in concentrated solution + Amount of albumin in residual test solution)/Amount of albumin in test solution} x 100

As a result of the measurement, the amount of albumin in the concentrated liquid and the residual test liquid was 27.5 g. Moreover, the albumin recovery rate was 80.6%.

When three concentrators from the same lot were tested (n = 3), the average albumin recovery rate calculated using equation (3) using the test solution, concentrated solution, and residual test solution was 79.9%, with a relative standard deviation of (RSD) was 0.0161 (1.61%).

Reference example 1
Concentration treatment was carried out in the same manner as in the example except that the protein concentration of the test solution in the example was adjusted to 4 g/dL.

Reference example 2
Concentration treatment was carried out in the same manner as in the example except that the protein concentration of the test solution in the example was adjusted to 7 g/dL.

<Evaluation>
The TMP (transmembrane pressure difference) during concentration of Examples and Reference Examples 1 and 2 was measured. The change in TMP during concentration in Examples is represented by TP2, the change in TMP during concentration in Reference Example 1 is represented by TP4, and the change in TMP during concentration in Reference Example 2 is represented by TP7, and the results are shown in FIG.

FIG. 3 shows that the TMP of the example is less than 150 mmHg during the test period (the medical time typically required for the patient, ie, 30 min to 60 min). On the other hand, in Reference Example 1, TMP was around 400 mmHg at 30 min, and in Reference Example 2, TMP was around 400 mmHg at 10 min.

From the above phenomena, it was found that the evaluation method of the example has no problems, test results with high reproducibility can be obtained, and performance tests can be performed accurately. This method can simulate the concentration situation during normal (repeated) use of the concentrator for human body cavity fluid concentration, and through the calculation process, the concentration performance of the concentrator during actual operation can be fundamentally understood. can do.

In Reference Example 1 and Reference Example 2, TMP (transmembrane pressure difference) increased in a short period of time (within 30 minutes). As a result, it was no longer possible to complete the test for the full processing time as scheduled. Furthermore, if the TMP rises too much, the membrane may be damaged and the container may be damaged, making it impossible to continue the test. In such cases, the performance of the concentrator during normal operation cannot be effectively predicted and there is no reliable reproducibility.

Although the present invention has been described above with reference to specific examples, those skilled in the art will understand that the present invention is not limited thereto.

The above description of embodiments of the invention is intended to be illustrative only and not exhaustive or restrictive. Those skilled in the art can make various modifications and changes without departing from the spirit and spirit of the above embodiments. The terminology used herein is employed to best explain the principles, practical applications and improvements to the prior art of the embodiments, and to enable those skilled in the art to understand the embodiments described herein. It is something.

The evaluation test method according to the present invention can be used for industrial evaluation of concentrators for human body cavity fluid.

1 Concentrator body 2 Concentrate output port (1st output port)
3 Concentrator input port 4 Filtrate output port (second output port)
5 Test liquid bag 6 Concentrate bag 7 Filtrate bag a/b/c circuit

Claims (14)

a concentration step of sending a test solution containing protein to a body cavity fluid concentrator and separating it into a concentrated solution and a filtrate;
a residual liquid recovery step of recovering residual test liquid remaining in the body cavity fluid concentrator after the concentration step;
a calculation step of measuring the components in the test liquid and the components in the concentrate and/or the filtrate and calculating the protein recovery performance of the body cavity fluid concentrator,
The total protein concentration of the test solution is 0.5 g/dL or more and 2.4 g/dL or less,
An evaluation test method for a body cavity fluid concentrator, characterized in that the number of blood cells in the test liquid is 1×10 ² cells/μL or less . The evaluation test method for a body cavity fluid concentrator according to claim 1, wherein the total protein concentration of the test liquid is 0.5 g/dL or more and 0.9 g/dL or less. The evaluation test method for a body cavity fluid concentrator according to claim 1, wherein the total protein concentration of the test liquid is 2.0 g/dL or more and 2.4 g/dL or less. The evaluation test method for a body cavity fluid concentrator according to claim 1, wherein the ratio of albumin to globulin (A/G ratio) of the test liquid is 0.8 or more and 1.5 or less. The body cavity fluid concentrator includes a porous membrane, an input port communicating with the primary side of the porous membrane, a first output port communicating with the primary side of the porous membrane, and a first output port communicating with the secondary side of the porous membrane. 2 output ports;
The concentration step includes:
The evaluation test method for a body cavity fluid concentrator according to any one of claims 1 to 4, wherein the test liquid is sent to the input port and the concentrated liquid is recovered from the first output port. The method for evaluating a body cavity fluid concentrator according to any one of claims 1 to 5, wherein the protein is at least one of albumin and α1-MG. The evaluation test method for a body cavity fluid concentrator according to any one of claims 1 to 6, wherein the protein recovery performance is an albumin recovery rate. The protein recovery performance is albumin recovery rate,
The evaluation test method for a body cavity fluid concentrator according to claim 7, wherein the calculation step measures albumin in the test liquid, the concentrated liquid, and the residual test liquid, and calculates the protein recovery performance of the body cavity fluid concentrator. . The evaluation test method for a body cavity fluid concentrator according to claim 8, wherein the albumin recovery rate is expressed by equation (3).
Formula (3)... Albumin recovery rate (%) = {(Amount of albumin in concentrated solution + Amount of albumin in residual test solution)/Amount of albumin in test solution} x 100 The evaluation test method for a body cavity fluid concentrator according to claim 8, wherein the albumin recovery rate is expressed by equation (4).
Formula (4)... Albumin recovery rate (%) = {(concentrated liquid amount x albumin concentration in the concentrated liquid + residual test liquid amount x albumin concentration in the residual test liquid) / (test liquid amount x albumin concentration in the test liquid) Albumin concentration)}×100 The evaluation test method for a body cavity fluid concentrator according to claim 1 or 4, wherein the protein recovery performance is α1-MG recovery rate or α1-MG permeability. Body cavity fluid concentration according to claim 11, wherein the calculation step measures α1-MG in the test liquid, the concentrated liquid, and the residual test liquid, and calculates the α1-MG recovery rate of the body cavity fluid concentrator. Equipment evaluation test method. The evaluation test method for a body cavity fluid concentrator according to claim 12, wherein the α1-MG recovery rate is expressed by equation (9).
Formula (9)...α1-MG recovery rate (%) = {(α1-MG amount in concentrated solution + α1-MG amount in residual test solution)/α1-MG amount in test solution}×100 The evaluation test method for a body cavity fluid concentrator according to claim 12, wherein the α1-MG recovery rate is expressed by equation (10).
Formula (10)... α1-MG recovery rate (%) = {(concentrated liquid amount x α1-MG concentration in concentrated liquid + residual test liquid amount x α1-MG concentration in residual test liquid) / (test liquid Amount x α1-MG concentration in test solution)} x 100