Filter for blood purification

Abstract

The application discloses a filter for blood purification, which comprises a shell, an end cover and a membrane filament. A high-bio-compatibility compound is added to the material of the membrane filament, so that the hydrophilicity of the membrane filament is enhanced. The mass proportion of the high-bio-compatibility compound on the inner surface of the membrane filament is controlled to be 15-50%, so that the hydrophilicity of the inner surface of the membrane filament is enhanced, the permeability of the membrane filament is improved, the interaction between proteins and the inner surface of the membrane filament is reduced, the irreversible adsorption amount of the proteins on the inner surface of the membrane filament is reduced, and the anti-pollution property of the membrane filament is improved, so that the service life of the filter for blood purification is prolonged.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of medical devices, in particular to a filter for blood purification. BACKGROUND

[0002] The filter for blood purification is used for removing solutes by convection and diffusion according to the filtration principle of kidney glomerulus. The filter for blood purification has good permeability. Water and small and medium molecular solutes in blood are removed under the action of convection and diffusion, and the pressure gradient (transmembrane pressure) on the two sides of the semi-permeable membrane of the filter for blood purification is used to remove water and solutes. Specifically, substances smaller than the filter membrane pores are filtered out (including substances required by the body and substances not required by the body), and the stability of the blood environment is maintained by relying on the concentration gradient of substances on the two sides of the blood side and the dialysate side.

[0003] The anti-pollution performance and permeability of the membrane wire of the filter for blood purification affect the service life of the filter for blood purification.

[0004] Therefore, how to prolong the service life of the filter for blood purification has become a technical problem to be solved by those skilled in the art.

[0005] CONTENT

[0006] The application provides a filter for blood purification to prolong the service life of the filter for blood purification.

[0007] In order to achieve the above-mentioned purpose, the application provides a filter for blood purification, which comprises a shell, end covers and a membrane wire, the two ends of the shell are provided with the end covers, and the shell is filled with the membrane wire.

[0008] The membrane wire is composed of polysulfone, PVP and a high biocompatibility compound, and the mass fraction of the high biocompatibility compound on the inner surface of the membrane wire is 15%-50%.

[0009] Preferably, in the filter for blood purification, the membrane wire is made by using a dry-wet process.

[0010] Preferably, in the filter for blood purification, the membrane wire is a wave-shaped membrane wire, the diameter of the membrane wire is 180-240 mu m, the compression bending length of the membrane wire is 5-12 mm, and the amplitude of the membrane wire is 0.03-0.7 mm.

[0011] Preferably, in the filter for blood purification, the diameter of the membrane wire is 190-240 mu m, the compression bending length of the membrane wire is 6-10 mm, and the amplitude of the membrane wire is 0.1-0.6 mm.

[0012] The mass fraction of the high biocompatibility compound on the inner surface of the membrane wire is 15%-45%.

[0013] Preferably, in the filter for blood purification, the length of the shell is 110-135mm, the inner diameter of the shell is 36-42mm, and the filling density of the membrane filaments in the shell is 45-55%,

[0014] The end of the end cover away from the shell is arc-shaped, and the height of the arc-shaped end is 2-8mm.

[0015] Preferably, in the filter for blood purification, the diameter of the membrane filaments is 180-230μm, the buckling length of the membrane filaments is 7-11mm, and the amplitude of the membrane filaments is 0.05-0.5mm;

[0016] The mass fraction of the high biocompatibility compound on the inner surface of the membrane filaments is 20%-50%.

[0017] Preferably, in the filter for blood purification, the length of the shell is 160-200mm, the inner diameter of the shell is 33-35mm, and the filling density of the membrane filaments in the shell is 47-52%,

[0018] The end of the end cover away from the shell is arc-shaped, and the height of the arc-shaped end is 3-9mm.

[0019] Preferably, in the filter for blood purification, the diameter of the membrane filaments is 185-240μm, the buckling length of the membrane filaments is 5-12mm, and the amplitude of the membrane filaments is 0.03-0.7mm;

[0020] The mass fraction of the high biocompatibility compound on the inner surface of the membrane filaments is 18%-48%.

[0021] Preferably, in the filter for blood purification, the length of the shell is 220-270mm, the inner diameter of the shell is 25-32mm, and the filling density of the membrane filaments in the shell is 47-54%,

[0022] The end of the end cover away from the shell is arc-shaped, and the height of the arc-shaped end is 4-10mm.

[0023] Preferably, in the filter for blood purification, the high biocompatibility compound is at least one of cellulose, polyetherimide, polylactic acid, heparin, or vitamins.

[0024] The filter for blood purification provided by the embodiment of the present application comprises a shell, an end cover and a membrane filament. The high biocompatibility compound is added to the material of the membrane filament, the hydrophilicity of the membrane filament is enhanced, the mass ratio of the high biocompatibility compound on the inner surface of the membrane filament is controlled to be 15-50%, the hydrophilicity of the inner surface of the membrane filament is enhanced, the permeability of the membrane filament is improved, the interaction between the protein and the inner surface of the membrane filament is reduced, the irreversible adsorption amount of the protein on the inner surface of the membrane filament is reduced, and the anti-pollution property of the membrane filament is improved, so that the technical effect of prolonging the service life of the filter for blood purification is achieved. BRIEF DESCRIPTION OF DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced below. Obviously, the drawings in the following description are only some examples or embodiments of the present application, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative labor, and the present application can also be applied to other similar scenarios according to the provided drawings. Unless it is obvious from the language environment or otherwise stated, the same reference numerals in the drawings represent the same structure or operation.

[0026] Fig. 1 is the front view of the filter for blood purification of the present application;

[0027] Fig. 2 is the structure diagram of the membrane filament of the filter for blood purification of the present application;

[0028] Fig. 3 is the structure diagram of the end cover of the filter for blood purification of the present application.

[0029] The drawings are described as follows:

[0030] 1, shell, 2, end cover, 3, membrane filament. DETAILED DESCRIPTION

[0031] The present application will be further described in detail below in combination with the drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the related application, but not to limit the application. The described embodiments are only a part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0032] It should be noted that, for the convenience of description, only the parts related to the application are shown in the drawings. The embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0033] It should be understood that the terms “system,” “device,” “unit,” and / or “module” as used in this application are a method for distinguishing different components, elements, parts, sections, or assemblies from one another. However, if other expressions can achieve the same purpose, the terms can be replaced by other expressions.

[0034] As shown in the present application and claims, unless the context clearly indicates otherwise, the words “one,” “an,” “a,” and / or “the” do not mean a single thing but can include a plurality. Generally, the terms “comprising” and “including” merely indicate the inclusion of the elements explicitly mentioned, and these steps and elements do not constitute an exclusive list of the steps or elements. The element defined by the phrase “comprising a” does not exclude the presence of additional identical elements in the process, method, article, or device including the element.

[0035] In the description of the embodiments of the present application, “ / ” means or unless otherwise specified, for example, A / B can mean A or B; “and / or” in this document is merely a description of the relationship between the associated objects, which means that there can be three relationships, for example, A and / or B, which means that there are three cases: A alone, A and B together, and B alone. In addition, in the description of the embodiments of the present application, “multiple” means two or more than two.

[0036] Hereinafter, the terms “first” and “second” are used only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined with “first” and “second” can explicitly or implicitly include one or more of the features.

[0037] Flowcharts are used in the present application to illustrate the operations performed by the system according to the embodiments of the present application. It should be understood that the preceding or subsequent operations are not necessarily performed in sequence. On the contrary, each step can be processed in reverse order or simultaneously. Meanwhile, other operations can be added to these processes, or one or more steps can be removed from these processes.

[0038] As shown in the present application and claims, unless the context clearly indicates otherwise, the words “one,” “an,” “a,” and / or “the” do not mean a single thing but can include a plurality. Generally, the terms “comprising” and “including” merely indicate the inclusion of the elements explicitly mentioned, and these steps and elements do not constitute an exclusive list of the steps or elements. The element defined by the phrase “comprising a” does not exclude the presence of additional identical elements in the process, method, article, or device including the element. Figs. 1-3

[0039] Some embodiments of the present application disclose a filter for blood purification, comprising a shell 1, an end cap 2, and a membrane filament 3.

[0040] The end cap 2 comprises a first end cap 2 and a second end cap 2, the first end cap 2 is provided with a blood inlet, and the second end cap 2 is provided with a blood outlet;

[0041] The shell 1 is a cylindrical shell 1, and the shell 1 is filled with the membrane filament 3.

[0042] ​The side wall of the first end and the second end of the shell 1 in the axial direction is respectively provided with a dialysate outlet and a dialysate inlet, the first end of the shell 1 is provided with a first end cover 2, and the second end of the shell 1 is provided with a second end cover 2.

[0043] The blood is supplied into the membrane filament 3 in the shell 1 through the blood inlet of the first end cover 2, the dialysate is supplied into the shell 1 from the dialysate inlet of the shell 1, the dialysate is located outside the membrane filament 3, the dialysate after dialysis is discharged through the dialysate outlet of the shell 1, and the blood is discharged through the blood outlet of the second end cover 2. The flow directions of the dialysate and the blood in the shell 1 are opposite.

[0044] In the application, the membrane filament 3 is composed of polysulfone, PVP and a high biocompatibility compound, wherein the mass ratio of the high biocompatibility compound on the inner surface of the membrane filament 3 is 15-50%.

[0045] In the application, the high biocompatibility compound is added to the material of the membrane filament 3, the hydrophilicity of the membrane filament 3 is enhanced, and especially the mass ratio of the high biocompatibility compound on the inner surface of the membrane filament 3 is limited. The mass ratio of the high biocompatibility compound on the inner surface of the membrane filament 3 is controlled to be 15-50% in the application, the hydrophilicity of the inner surface of the membrane filament 3 is enhanced, the permeability of the membrane filament 3 is improved, the interaction between the protein and the inner surface of the membrane filament 3 is reduced, the irreversible adsorption amount of the protein on the inner surface of the membrane filament 3 is reduced, the anti-pollution property of the membrane filament 3 is improved, and the service life of the filter for blood purification is prolonged.

[0046] Table 1:

[0047]

[0048] In the table, the pressure drop represents the flow resistance and the kinetic stability, the smaller the pressure drop value is, the smaller the resistance of the filter for blood purification to the blood is, and the more stable the flow is; the service life is indicated by the pressure value after running for 4 hours, the smaller the pressure increase value is, the longer the service life is; the clearance performance of small and medium molecular substances adopts VB 12 The clearance performance of small and medium molecular substances is used as an index, the higher the clearance performance of small and medium molecular substances is, the higher the clearance ability of small and medium molecular substances is; the clearance ability of large and medium molecular substances adopts the clearance ability of β2 microglobulin as an index, the higher the clearance performance of large and medium molecular substances is, the higher the clearance ability of large and medium molecular substances is.

[0049] The above table shows that when the shell length L, the shell inner diameter D, the filling density, the end cover arc height h, the membrane filament diameter d, the membrane filament pressure bending length l and the membrane filament pressure bending amplitude λ are all unchanged, the increase of the mass ratio of the high biocompatibility compound will reduce the pressure drop, improve the clearance performance, prolong the service life and increase the clearance performance of medium molecular substances.

[0050] As can be seen from the above table, when the mass ratio of the high biocompatibility compound on the inner surface of the membrane filament 3 is 15%-50%, the pressure increase value of the blood purification filter after running for 4 hours is lower than that of the blood purification filter without the high biocompatibility compound in the prior art, indicating that the service life of the blood purification filter with the high biocompatibility compound is prolonged.

[0051] At the same time, the pressure drop is reduced, indicating that the resistance of the blood purification filter to blood is reduced, the flow is stable, and the influence on the hemodynamic stability of the patient is reduced.

[0052] In addition, the blood purification filter has improved clearance performance for small and medium molecules and large molecules.

[0053] In the present application, the membrane filament 3 is made by a dry-wet process.

[0054] The high biocompatibility compound is at least one of cellulose, polyetherimide, polylactic acid, heparin or a vitamin.

[0055] In the present application, the membrane filament 3 is a wave-shaped membrane filament, the diameter of the wave-shaped membrane filament is 180-240 μm, the compression length l of the membrane filament 3 is 5-12 mm, and the amplitude of the membrane filament 3 is 0.03-0.7 mm.

[0056] In some embodiments of the present application, the diameter of the membrane filament 3 is 190-240 μm, the compression length l of the membrane filament 3 is 6-10 mm, and the amplitude of the membrane filament 3 is 0.1-0.6 mm.

[0057] The mass ratio of the high biocompatibility compound on the inner surface of the membrane filament 3 is 15-45%.

[0058] The length of the shell 1 is 110-135 mm, the inner diameter of the shell 1 is 36-42 mm, and the filling density of the membrane filament 3 in the shell 1 is 45-55%.

[0059] The end cover 2 away from the shell 1 is arc-shaped, and the height of the arc-shaped is 2-8 mm.

[0060] The filling density is the ratio of the sum of the cross-sectional areas of the membrane filaments to the cross-sectional area of the shell 1.

[0061] Table 2:

[0062]

[0063] According to Table II, it can be seen that the length of the shell 1 is shortened, the inner diameter of the shell 1 is increased, the filling density is increased, and the pressure drop of the blood purification filter is obviously reduced, which is about 30% of the pressure drop in the prior art. It is indicated that the smaller the resistance of the blood purification filter to blood, the more stable the flow, and the influence on the hemodynamic stability of the patient is reduced.

[0064] According to Table II, it can be seen that after the high biocompatibility compound is added, the pressure increase value of the blood purification filter after running for 4 hours is lower than the pressure increase value of the blood purification filter without adding the high biocompatibility compound in the prior art, and is reduced to about 30% of the prior art. It is indicated that the service life of the blood purification filter with the added high biocompatibility compound is prolonged.

[0065] According to Table II, it can be seen that after the high biocompatibility compound is added, the clearance performance of the blood purification filter to small and medium molecules and large molecules is not obviously improved.

[0066] In some embodiments of the present application, the diameter of the membrane wire 3 is 180-230 μm, the buckling length l of the membrane wire 3 is 7-11 mm, the amplitude of the membrane wire 3 is 0.05-0.5 mm,

[0067] The mass fraction of the high biocompatibility compound on the inner surface of the membrane wire 3 is 20-50%;

[0068] The length of the shell 1 is 160-200 mm, the inner diameter of the shell 1 is 33-35 mm, and the filling density of the membrane wire 3 in the shell 1 is 47-52%,

[0069] The end of the end cover 2 away from the shell 1 is arc-shaped, and the height of the arc-shaped is 3-9 mm.

[0070] Table III:

[0071]

[0072] According to Table III, it can be seen that the length of the shell 1 is shortened, the inner diameter of the shell 1 is reduced, the filling density is increased, and the pressure drop of the blood purification filter is obviously reduced. It is indicated that the smaller the resistance of the blood purification filter to blood, the more stable the flow, and the requirement for the hemodynamic stability of the patient is reduced.

[0073] According to Table III, it can be seen that after the high biocompatibility compound is added, the pressure increase value of the blood purification filter after running for 4 hours is lower than the pressure increase value of the blood purification filter without adding the high biocompatibility compound in the prior art. It is indicated that the service life of the blood purification filter with the added high biocompatibility compound is prolonged.

[0074] According to Table Three, it can be seen that the blood purification filter has improved performance in removing small and medium molecules after adding the high biocompatibility compound.

[0075] According to Table Three, it can be seen that the blood purification filter has not significantly improved performance in removing medium and large molecules after adding the high biocompatibility compound.

[0076] The blood purification filter corresponding to Table Two and Table Three can greatly reduce the pressure drop and reduce the impact on the hemodynamic stability of the patient, but the length of the shell of the blood purification filter in Table Three is relatively increased compared to the length of the shell of the blood purification filter in Table Two, but the inner diameter of the shell of the blood purification filter in Table Three is relatively reduced compared to the inner diameter of the shell of the blood purification filter in Table Two, the hemodynamic stability of the blood purification filter corresponding to Table Two is relatively low, the service life of the blood purification filter corresponding to Table Three is relatively long, and the blood purification filter corresponding to Table Three has stronger performance in removing small and medium molecules and medium and large molecules.

[0077] In some embodiments of the present application, the diameter of the membrane wire 3 is 185-240 μm, the buckling length l of the membrane wire 3 is 5-12 mm, the amplitude of the membrane wire 3 is 0.03-0.7 mm,

[0078] The mass fraction of the high biocompatibility compound on the inner surface of the membrane wire 3 is 18-48%;

[0079] The length of the shell 1 is 220-270 mm, the inner diameter of the shell 1 is 25-32 mm, and the filling density of the membrane wire 3 in the shell 1 is 47-54%,

[0080] The end of the end cover 2 away from the shell 1 is a circular arc, and the height of the circular arc is 4-10 mm.

[0081] Table Four:

[0082]

[0083] According to Table Four, it can be seen that the length of the shell 1 is increased, the inner diameter of the shell 1 is reduced, and the filling density is increased, and the pressure drop of the blood purification filter is not obvious, and the impact of the blood purification filter on the hemodynamic stability of the patient is not significantly reduced.

[0084] According to Table Four, it can be seen that the pressure increase value of the blood purification filter after running for 4 hours is lower than the pressure increase value of the blood purification filter without adding the high biocompatibility compound in the prior art after running for 4 hours, indicating that the service life of the blood purification filter with the high biocompatibility compound is prolonged.

[0085] According to Table Four, the blood purification filter can improve the removal of both small and medium molecules and medium and large molecules after adding the high biocompatibility compound.

[0086] Increasing the length of the shell and reducing the inner diameter of the shell increases the packing density, increases the pressure difference between the two sides of the dialysate and blood chamber, increases the convection, and thus increases the removal of medium and large molecules.

[0087] The blood purification filter corresponding to Table Four can further increase the length of the shell and further reduce the inner diameter of the shell, and can greatly prolong the service life of the blood purification filter, but has a greater impact on the hemodynamic stability of the patient's blood, and enhances the removal of medium and large molecules.

[0088] Table Five:

[0089]

[0090] According to Table Five, under the premise that the length of the shell 1 is shortened, the inner diameter of the shell 1 is increased, and the packing density is increased, the length of the shell 1, the inner diameter of the shell 1, the packing density, the arc height h of the end cap, the membrane wire diameter d, the bending amplitude λ of the membrane wire, and the proportion of the hydrophilic substance remain unchanged. The smaller the bending length l of the membrane wire 3, the greater the impact on the hemodynamic stability of the patient's blood, and the service life is relatively shortened, the removal of small and medium molecules is not significantly improved, but the removal of medium and large molecules is reduced.

[0091] Table Six:

[0092]

[0093] According to Table Six, under the premise that the length of the shell 1 is shortened, the inner diameter of the shell 1 remains unchanged, and the packing density is increased, the length of the shell 1, the inner diameter of the shell 1, the packing density, the arc height h of the end cap, the membrane wire diameter d, the bending length l of the membrane wire, and the proportion of the hydrophilic substance remain unchanged. The greater the bending amplitude λ of the membrane wire 3, the greater the impact on the hemodynamic stability of the patient's blood, and the service life is relatively shortened, the removal of small and medium molecules is improved, but the removal of medium and large molecules is reduced.

[0094] Table Seven:

[0095]

[0096] According to Table Seven, under the premise that the length of the shell 1 is lengthened, the inner diameter of the shell 1 is reduced, and the filling density is increased, when the length of the shell 1, the inner diameter of the shell 1, the filling density, the cake arc height h, the membrane wire diameter d, the membrane wire bending length l and the membrane wire bending amplitude λ are unchanged, the higher the mass of the high biocompatibility compound is, the lower the influence on the hemodynamic stability of the patient is, and the service life is relatively prolonged, and the clearance ability of the macromolecules is enhanced.

[0097] The height of the end cap is too low to reduce the pressure of the end cap, which affects the stability of the blood, and the height of the end cap is too high to cause the blood to be retained at the end cap, which also affects the stability of the blood. The application also relates to the improvement of the arc height of the end cap, and the reduction of the arc height of the end cap reduces the influence on the uniformity of the blood flowing in the dialyzer and the stability of the blood flow.

[0098] The above description is only the preferred embodiment of the application and the explanation of the applied technical principles, and is not used to limit the application. For those skilled in the art, the application can have various changes and variations. The application range involved in the application is not limited to the technical solutions formed by the specific combination of the above technical features, and should also cover other technical solutions formed by the combination of the above technical features or equivalent features without departing from the above application concept. For example, the above features are replaced with the technical features disclosed in the application (but not limited to) having similar functions to form the technical solutions.

Claims

1. A filter for blood purification, characterized by comprising: It includes a housing (1), end caps (2) and membrane fibers (3), with the end caps (2) installed at both ends of the housing (1) and the membrane fibers (3) filling the housing (1). The membrane fiber (3) is composed of polysulfone, PVP and a highly biocompatible compound, wherein the highly biocompatible compound accounts for 15%-50% of the mass of the inner surface of the membrane fiber (3); The membrane fiber (3) is a wavy membrane fiber, the bending length of the membrane fiber (3) is 5-12mm, and the bending amplitude of the membrane fiber (3) is 0.03-0.7mm; The shell (1) has a length of 110-135 mm, an inner diameter of 36-42 mm, and a filling density of 3 membrane fibers in the shell (1) of 45-55%; or the shell (1) has a length of 160-200 mm, an inner diameter of 33-35 mm, and a filling density of 3 membrane fibers in the shell (1) of 47-52%; or the shell (1) has a length of 220-270 mm, an inner diameter of 25-32 mm, and a filling density of 3 membrane fibers in the shell (1) of 47-54%. After the blood purification filter has been running for 4 hours, the pressure increase is reduced and the service life is extended. The highly biocompatible compound is at least one of cellulose, polyetherimide, polylactic acid, heparin, or vitamin.

2. The blood purification filter according to claim 1, characterized in that, The membrane fiber (3) is manufactured using a dry-wet process.

3. The blood purification filter according to claim 1, characterized in that, The diameter of the membrane filament (3) is 180-240 μm.

4. The blood purification filter according to claim 3, characterized in that, The diameter of the membrane fiber (3) is 190-240 μm, the bending length of the membrane fiber (3) is 6-10 mm, and the amplitude of the membrane fiber (3) is 0.1-0.6 mm. The highly biocompatible compound accounts for 15%-45% of the mass of the inner surface of the membrane filament (3).

5. The blood purification filter according to claim 4, characterized in that, The end cap (2) away from the housing (1) is arc-shaped, and the height of the arc is 2-8mm.

6. The blood purification filter according to claim 3, characterized in that, The diameter of the membrane fiber (3) is 180-230 μm, the bending length of the membrane fiber (3) is 7-11 mm, and the amplitude of the membrane fiber (3) is 0.05-0.5 mm. The highly biocompatible compound accounts for 20%-50% of the mass of the inner surface of the membrane filament (3).

7. The blood purification filter according to claim 6, characterized in that, The end cap (2) away from the housing (1) is arc-shaped, and the height of the arc is 3-9mm.

8. The blood purification filter according to claim 3, characterized in that, The diameter of the membrane fiber (3) is 185-240 μm, the bending length of the membrane fiber (3) is 5-12 mm, and the amplitude of the membrane fiber (3) is 0.03-0.7 mm. The highly biocompatible compound accounts for 18%-48% of the mass of the inner surface of the membrane filament (3).

9. The blood purification filter according to claim 8, characterized in that, The end cap (2) away from the housing (1) is arc-shaped, and the height of the arc is 4-10mm.

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