METHOD FOR WHOLE BLOOD FILTRATION AND FILTER MEMBRANE STRUCTURE FOR WHOLE BLOOD FILTRATION

Abstract

Disclosed are a method for whole blood filtration and a filter membrane structure for whole blood filtration, specifically including the following steps: (1) a filter membrane structure made up of at least two filtration membranes sequentially stacked from top to bottom is selected, and subjected to hemagglutinin treatment for later use; (2) a whole blood sample is added to the filter membrane structure for filtration; and (3) the filtered serum or plasma is collected. The filter membrane structure is composed of at least two filtration membranes stacked from top to bottom, and the pore sizes of the filtration membranes stacked gradually decrease from top to bottom, and the areas of the same gradually increase or are equal to each other from top to bottom.

Claims

1. A method for whole blood filtration, comprising the following steps: (1) selecting a filter membrane structure made up of at least two filtration membranes sequentially stacked from top to bottom, and subjecting the filter membrane structure to hemagglutinin treatment for later use; (2) adding a whole blood sample to the filter membrane structure for filtration; and (3) collecting the filtered serum or plasma.

2. The method for whole blood filtration according to claim 1, wherein the filtration membranes are porous structure; pore sizes of the filtration membranes stacked in the filter membrane structure gradually decrease from top to bottom, and areas of the filtration membranes gradually increase or are equal to each other from top to bottom.

3. The method for whole blood filtration according to claim 1, wherein the filter membrane structure comprises two filtration membranes, which are an upper filtration membrane and a lower filtration membrane, respectively, the upper filtration membrane is a hemagglutinin filter membrane, and the lower filtration membrane is composed of at least one hydrophilic microporous membrane; or the upper filtration membrane is a hydrophilic filtration membrane, and the lower filtration membrane is a hemagglutinin filter membrane; hemagglutinin is uniformly distributed in the hemagglutinin filter membrane.

4. The method for whole blood filtration according to claim 3, wherein the upper filtration membrane is a hemagglutinin filter membrane; the lower filtration membrane is a filtration membrane with evenly distributed filter pores and different pore sizes, or the lower filtration membrane is composed of a first lower membrane and a second lower membrane stacked one on another in sequence, and a pore size of the first lower membrane is larger than a pore size of the second lower membrane.

5. The method for whole blood filtration according to claim 3, wherein the upper filtration membrane is a glass fiber filter paper or a nitrocellulose membrane or a polysulfone membrane; the lower filtration membrane is a hydrophilic microporous membrane, including a glass fiber filter paper or a nitrocellulose membrane or a polysulfone membrane or a cellulose acetate membrane; the filtration in step (2) is accelerated by upper pressurization or lower suction.

6. The method for whole blood filtration according to claim 3, wherein the hemagglutinin filter membrane is obtained by subjecting the filtration membrane to hemagglutinin treatment, and a preparation process thereof is as follows: 1) diluting hemagglutinin in a hemagglutinin buffer; and 2) putting the filtration membrane into the hemagglutinin buffer containing hemagglutinin in step 1) to get wetted, air-drying the filtration membrane at room temperature, and then placing the filtration membrane in an oven at 37 C.-55 C. for more than 2 h; or subjecting the filtration membrane wetted in the hemagglutinin buffer to vacuum drying or freeze-drying treatment.

7. The method for whole blood filtration according to claim 6, wherein the hemagglutinin buffer is PB or Tris-HCl or CB; a concentration of the hemagglutinin buffer is 5 mM-1M; a weight of hemagglutinin added to the hemagglutinin filter membrane is not less than 5 ng.

8. The method for whole blood filtration according to claim 3, wherein the filtration membrane is treated with a buffer before use, and the buffer is any buffer dissolved with BSA or an amino acid, or containing a surfactant component; a treatment process is: after being wetted in the buffer, the filtration membrane is air-dried at room temperature and dried for more than 2 h for later use.

9. The method for whole blood filtration according to claim 6, wherein a pore size of the upper filtration membrane is not less than 0.45 m, and a pore size of the lower filtration membrane is 0.2 m-4 m.

10. The method for whole blood filtration according to claim 9, wherein characterized in that, the pore size of the upper filtration membrane is 1 m-5 m; a thickness of the upper filtration membrane is 0.5 mm-20 mm, and a thickness of the lower filtration membrane is 0.05 mm-2 mm; a weight of hemagglutinin added in the hemagglutinin filter membrane is 20 ng-100 ng.

11. A filter membrane structure for whole blood filtration, wherein the filter membrane structure is composed of at least two filtration membranes stacked in sequence from top to bottom; the filtration membranes are of porous structure; pore sizes of the filtration membranes stacked in the filter membrane structure gradually decrease from top to bottom, and areas of the filtration membranes gradually increase or are equal to each other from top to bottom.

12. The filter membrane structure for whole blood filtration according to claim 11, wherein the filter membrane structure comprises two filtration membranes, which are an upper filtration membrane and a lower filtration membrane, respectively, the upper filtration membrane is a hemagglutinin filter membrane, and the lower filtration membrane is composed of at least one hydrophilic microporous membrane; or the upper filtration membrane is a hydrophilic filtration membrane, and the lower filtration membrane is a hemagglutinin filter membrane; hemagglutinin is uniformly distributed in the hemagglutinin filter membrane.

13. The filter membrane structure for whole blood filtration according to claim 12, wherein the upper filtration membrane is a hemagglutinin filter membrane; the lower filtration membrane is a filtration membrane with evenly distributed filter pores and different pore sizes, or the lower filtration membrane is composed of a first lower membrane and a second lower membrane stacked one on another in sequence, and a pore size of the first lower membrane is larger than a pore size of the second lower membrane.

14. The filter membrane structure for whole blood filtration according to claim 12, wherein a pore size of the upper filtration membrane is not less than 0.45 m, and a pore size of the lower filtration membrane is 0.2 m-4 m.

15. The filter membrane structure for whole blood filtration according to claim 12, wherein a pore size of the upper filtration membrane is 1 m-5 m; a thickness of the upper filtration membrane is 0.5 mm-20 mm, and a thickness of the lower filtration membrane is 0.05 mm-2 mm; a weight of hemagglutinin added in the hemagglutinin filter membrane is 20 ng-100 ng.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The following is a further detailed description in conjunction with the accompanying drawings and embodiments of the present invention:

[0036] FIG. 1 is a flowchart of a method for whole blood filtration according to the present invention;

[0037] FIG. 2 is a longitudinal cross section of a filter membrane structure for whole blood filtration in Example 31 and Example 33 according to the present invention; and

[0038] FIG. 3 is a longitudinal cross section of a filter membrane structure for whole blood filtration in Example 32 according to the present invention;

[0039] in which: 1upper filtration membrane; 2lower filtration membrane; 201first lower membrane; and 202second lower membrane.

DESCRIPTION OF THE EMBODIMENTS

[0040] Example 1: A filter membrane structure includes two filtration membranes, which are an upper filtration membrane 1 and a lower filtration membrane 2, respectively. The upper filtration membrane 1 is a glass fiber paper with a thickness of 0.5 mm and a pore size of 5 m. RBC antibody (red blood cell antibody, a hemagglutinin) is dissolved in PB buffer with, and this is used to treat the upper filtration membrane 1 so that the content of RBC antibody in the upper filtration membrane 1 is 100 ng. Then, it is placed in an oven at 37 C.-55 C. to dry for more than 2 h.

[0041] The lower filtration membrane 2 is a glass fiber paper with a thickness of 1 mm, and treated with PB buffer dissolved with 1% BSA; and air-dried at room temperature and dried for more than 2 hours.

[0042] As shown in FIG. 1, the method for whole blood filtration specifically includes the following steps:

[0043] (1) the above filter membrane structure is selected;

[0044] (2) a whole blood sample is added to the filter membrane structure for filtration; the upper pressurization filtration speed is used in the filtration; and

[0045] (3) a collecting device is set up to collect the filtered serum or plasma.

[0046] In the case of active pressure 20 MPa for filtration, the filtration effect can complete the filtration of serum in normal 200 L whole blood within 30 s, and the filtered serum can reach more than 60 L.

[0047] Examples 2 to 4 all use the filter membrane structure of Example 1 above, and also the same method for whole blood filtration; the difference from Example 1 is the thickness of the upper filtration membrane 1 and the lower filtration membrane 2. The filtration time and the amount of serum collected are shown in Table 1 below.

TABLE-US-00001 TABLE 1 Results of whole blood filtration for Examples 1 to 4 Thickness Thickness Volume of upper of lower Average of filtration filtration filtration serum With or without membrane membrane time filtered blood cells Example (mm) (mm) (s) (L) filtered through Example 0.5 1 27 65 None 1 Example 0.25 1 17 70 Some blood cells 2 Example 0.5 2 65 50 None 3 Example 0.25 2 60 50 None 4

[0048] It can be seen form table 1 that Example 1 has achieved the best effect.

[0049] Examples 5 to 7 all use the filter membrane structure of Example 1 above, and also the same method for whole blood filtration; the difference from Example 1 is the pressure applied in the filtration in step (2). The filtration conditions are shown in Table 2 below.

TABLE-US-00002 TABLE 2 Results of whole blood filtration for Examples 1, 5 to 7 Air Average Volume of With or without pressure filtration time serum blood cells Example (MPa) (s) filtered (L) filtered through Example 1 20 27 65 None Example 5 5 62 55 None Example 6 10 48 55 None Example 7 30 18 65 Some broken hemolytic red blood cells are filtered through

[0050] It can be seen form table 2 that Example 1 has achieved the best effect.

[0051] Examples 8 to 15 all use the whole blood filtration method of Example 1 above, and also the same parameters in the filtration. The filter membrane structure also uses the filter membrane structure of Example 1 above. The difference from Example 1 is the selected materials of the upper filtration membrane 1 and the lower filtration membrane 2 in the filter membrane structure. The filtration conditions are shown in Table 3 below.

TABLE-US-00003 TABLE 3 Results of whole blood filtration for Examples 1, 8 to 15 Volume With or of without Upper Lower Average serum blood cells filtration filtration filtration filtered filtered Example membrane membrane time (s) (L) through Example Glass fiber Glass fiber 27 65 None 1 paper paper Example Glass fiber Polysulfone 32 65 None 8 paper membrane Example Polysulfone Polysulfone 35 65 Some 9 membrane membrane blood cells Example Nitrocellulose Polysulfone 48 50 Some 10 membrane membrane blood cells Example Glass fiber Nitrocellulose 37 60 None 11 paper membrane Example Polysulfone Nitrocellulose 38 65 Some 12 membrane membrane blood cells Example Nitrocellulose Nitrocellulose 45 65 Some 13 membrane membrane blood cells Example Polysulfone Glass fiber 42 60 Some 14 membrane paper blood cells Example Nitrocellulose Glass fiber 52 60 None 15 membrane paper

[0052] It can be seen form table 3 that Example 1 has achieved the best effect.

[0053] Example 16: Ferric chloride is used as hemagglutinin in this example; taking a 200 L whole blood sample as an example, when the whole blood sample contains 50% serum, the structure can filter out no less than 50 L volume of serum, the amount of serum filtered is more than 50%; the filter membrane structure includes two filtration membranes, which are an upper filtration membrane 1 and a lower filtration membrane 2, respectively. The upper filtration membrane 1 is a glass fiber paper with a thickness of 0.5 mm and a pore size of 5 m. The upper filtration membrane 1 is treated with a ferric chloride solution with a concentration of 50 mM so that ferric chloride is evenly distributed in the upper filtration membrane 1, and the content of ferric chloride is 100 ng.

[0054] The lower filtration membrane 2 is a glass fiber paper with a thickness of 1 mm, and treated with PB buffer dissolved with 1% BSA; and air-dried at room temperature and dried for more than 2 hours.

[0055] As shown in FIG. 1, the method for whole blood filtration specifically includes the following steps:

[0056] (1) the above filter membrane structure is selected;

[0057] (2) a whole blood sample is added to the filter membrane structure for filtration; the upper pressurization filtration speed is used in the filtration; and

[0058] (3) a collecting device is set up to collect the filtered serum or plasma.

[0059] In the case of active pressure 20 MPa for filtration, the filtration effect can complete the filtration of serum in normal 200 L whole blood within 60 s, and the filtered serum can reach more than 60 L.

[0060] Examples 17 to 19 all use the filter membrane structure of Example 16 above, and the same treatment method of the filter membrane structure and the same method for whole blood filtration; the difference from Example 16 is the thickness of the upper filtration membrane 1 and the lower filtration membrane 2. The filtration time and the amount of serum collected are shown in Table 4 below.

TABLE-US-00004 TABLE 4 Results of whole blood filtration for Examples 16 to 19 Thickness of Thickness With or upper of lower Volume without filtration filtration Average of serum blood cells membrane membrane filtration filtered filtered Example (mm) (mm) time (s) (L) through Example 16 0.5 1 58 60 None Example 17 0.25 1 52 62 Some blood cells Example 18 0.5 2 113 40 None Example 19 0.25 2 106 42 None

[0061] It can be seen form table 4 that Example 16 has achieved the best effect.

[0062] Examples 20 to 22 all use the filter membrane structure of Example 16 above, and the same treatment method for the filter membrane structure and the same method for whole blood filtration; the difference from Example 16 is the pressure applied on the upper portion in the filtration in step (2). The filtration conditions are shown in Table 5 below.

TABLE-US-00005 TABLE 5 Results of whole blood filtration for Examples 16, 20 to 22 Air Average Volume of With or without pressure filtration serum filtered blood cells Example (MPa) time (s) (L) filtered through Example 16 20 58 60 None Example 20 5 114 45 None Example 21 10 87 47 None Example 22 30 52 61 Some broken hemolytic red blood cells are filtered through

[0063] It can be seen form table 5 that Example 16 has achieved the best effect.

[0064] Examples 23 to 30 all use the whole blood filtration method of Example 16 above, and the same parameters in the filtration. The filter membrane structure also uses the filter membrane structure of Example 16 above and is treated with the same treatment method. The difference from Example 16 is the selected materials of the upper filtration membrane 1 and the lower filtration membrane 2 in the filter membrane structure. The filtration conditions are shown in Table 6 below.

TABLE-US-00006 TABLE 6 Results of whole blood filtration for Examples 16, 23 to 30 With or Volume without Upper Lower Average of serum blood cells filtration filtration filtration filtered filtered Example membrane membrane time (s) (L) through Example Glass fiber Glass fiber 58 60 None 16 paper paper Example Glass fiber Polysulfone 75 59 None 23 paper membrane Example Polysulfone Polysulfone 76 60 Some blood 24 membrane membrane cells Example Nitrocellulose Polysulfone 94 45 Some blood 25 membrane membrane cells Example Glass fiber Nitrocellulose 78 55 None 26 paper membrane Example Polysulfone Nitrocellulose 81 60 Some blood 27 membrane membrane cells Example Nitrocellulose Nitrocellulose 83 58 Some blood 28 membrane membrane cells Example Polysulfone Glass fiber 42 60 Some blood 29 membrane paper cells Example Nitrocellulose Glass fiber 52 60 None 30 membrane paper

[0065] It can be seen form table 6 that Example 16 has achieved the best effect.

[0066] Example 31: As shown in FIG. 2, the filter membrane structure for whole blood filtration is composed of two filtration membranes stacked in sequence from top to bottom; the filtration membranes are of porous structure; the pore sizes of the filtration membranes stacked in the filter membrane structure gradually decrease from top to bottom, and the areas of the same gradually increase from top to bottom; the two filtration membranes included in the filter membrane structure are an upper filtration membrane 1 and a lower filtration membrane 2, respectively, the upper filtration membrane 1 is a hemagglutinin filter membrane, the lower filtration membrane 2 is a filtration membrane with evenly distributed filter pores and different pore sizes; the pore size of the upper filtration membrane 1 is 1 m, and the pore size of the lower filtration membrane 2 is 0.2-0.5 m; the thickness of the upper filtration membrane 1 is 0.5 mm, and the thickness of the lower filtration membrane 2 is 1 mm; the hemagglutinin filter membrane is a filtration membrane treated with hemagglutinin, in which hemagglutinin is evenly distributed, and the weight of hemagglutinin is 100 ng.

[0067] Example 32: As shown in FIG. 3, the difference from Example 31 is that the lower filtration membrane 2 is composed of a first lower membrane 201 and a second lower membrane 202 stacked in sequence from top to bottom, and the first lower membrane 201 has a pore size larger than that of the second lower membrane 202. Specifically: the filter membrane structure for whole blood filtration is composed of two filtration membranes stacked in sequence from top to bottom; the filtration membranes are of porous structure; the pore sizes of the filtration membranes stacked in the filter membrane structure gradually decrease from top to bottom, and the areas of the same gradually increase from top to bottom; the two filtration membranes included in the filter membrane structure are an upper filtration membrane 1 and a lower filtration membrane 2, respectively, the upper filtration membrane 1 is a hemagglutinin filter membrane, and the lower filtration membrane 2 is composed of a first lower membrane 201 and a second lower membrane 202 stacked in sequence from top to bottom, and the pore size of the first lower membrane 201 is larger than that of the second lower membrane 202. The pore size of the first lower membrane 201 is 0.5 m, and the pore size of the second lower membrane 202 is 0.2 m; the thickness of the upper filtration membrane 1 is 0.5 mm, and the total thickness of the lower filtration membrane 2 is 1 mm, where the thickness of the first lower membrane 201 is 0.5 mm, and the thickness of the second lower membrane 202 is 0.5 mm.

[0068] Example 33: As shown in FIG. 2, the difference from Example 31 is that the upper filtration membrane 1 is a hydrophilic filtration membrane, and the lower filtration membrane 2 is a hemagglutinin filter membrane. Specifically: the filter membrane structure for whole blood filtration is composed of two filtration membranes stacked in sequence from top to bottom; the filtration membranes are of porous structure; the pore sizes of the filtration membranes stacked in the filter membrane structure gradually decreases from top to bottom, and the areas of the same gradually increase from top to bottom; the two filtration membranes included in the filter membrane structure are an upper filtration membrane 1 and a lower filtration membrane 2, respectively, the upper filtration membrane 1 is a hydrophilic filtration membrane, and the lower filtration membrane 2 is hemagglutinin filter membrane; the pore size of the upper filtration membrane 1 is 1 m, the pore size of the lower filtration membrane 2 is 0.2-0.5 m; the thickness of the upper filtration membrane 1 is 0.5 mm, and the thickness of the lower filtration membrane 2 is 1 mm; the hemagglutinin filter membrane is a filtration membrane treated with hemagglutinin, in which hemagglutinin is evenly distributed, and the weight of hemagglutinin is 100 ng.

[0069] The filter membrane structure includes at least two filtration membranes, and more filtration membranes may also be stacked. The filtration membranes are of porous structure, and the uppermost layer is a loose porous structure, that is, the pore size of the uppermost layer is the largest, and the pore sizes of the stacked filtration membranes in the filter membrane structure gradually decrease from top to bottom. Such a design facilitates layer-by-layer filtration and the passage of plasma or serum, and prevents blood cells and other impurities. The areas of the filtration membranes stacked in the filter membrane structure can be equal to each other from top to bottom, or gradually increase from top to bottom. Such a design facilitates layer-by-layer filtration, and ensures that blood cells and other impurities leaked from the upper layer can further be filtered by the lower layer.

[0070] The basic principles, main features and advantages of the present invention have been shown and described above. Those skilled in the art should understand that the present invention is not limited to the foregoing examples. The foregoing examples and the description in the specification are only intended to illustrate the principles of the present invention. Various variations and improvements may further be made to the present invention without departing from the spirit and scope of the present invention. For example, the materials of the filtration membranes or the pore sizes of the same, etc. are changed. Such variations and improvements all fall within the scope claimed by the present invention. The scope claimed by the present invention is defined by the appended claims and their equivalents.