Hollow fiber membrane for blood purification and blood purification apparatus using the same

Patent metadata

Field	Value
Publication number	US-9849427-B2
Application number	US-57944904-A
Country	US
Kind code	B2
Filing date	Nov 17, 2004
Priority date	Nov 17, 2003
Publication date	Dec 26, 2017
Grant date	Dec 26, 2017

Abstract

An object of the present invention is to provide a hollow fiber membrane with enhanced phosphorus-removing performance without impairing antithrombogenicity in order to inhibit in vivo accumulation of phosphate ions in living body that might cause bone metabolism disorders.
The present inventors have found that a hollow fiber membrane having a specific membrane structure and a specific membrane composition possesses a very useful range for inner surface charges of the membrane. More particularly, the inventors have discovered that the above object can be achieved in a limited range in which the zeta potential on the inner surface of a hollow fiber membrane measured under given certain conditions is greater than −3.0 mV but less than 0 mV. This finding has led to the completion of the present invention.

First claim

The invention claimed is:

1. A hollow fiber membrane for blood purification having an integrally continuous structure from the inner membrane surface to the outer membrane surface and comprising a hydrophobic polymer and a hydrophilic polymer, and
the hollow fiber membrane comprising a polyvinyl pyrrolidone as the hydrophilic polymer in the range of 3.0 to 5.0 wt % based on the hollow fiber membrane,
exhibiting a zeta potential on the inner surface thereof of greater than −3.0 mV but less than 0 mV at pH 7.5, when measured using a sample with an embedded resin on the outer side for allowing the electrolyte solution to flow through only the inside of the hollow fiber, and using a 0.001 mol/l potassium chloride aqueous solution as an electrolyte solution.

2. The follow fiber membrane for blood purification according to claim 1 , further exhibiting:
(a) a polyvinyl pyrrolidone sieving coefficient of 45% or more in a filtration test using a polyvinyl pyrrolidone aqueous solution with a weight average molecular weight of 40,000,
(b) a protein adsorption amount of 65 mg/m 2 or less,
(c) a breaking strength of 60 kg/cm 2 or more, and
(d) a breaking elongation of 60% or more.

3. The hollow fiber membrane for blood purification according to claim 2 , wherein an overall mass transfer coefficient of phosphorous is 0.040 cm/min or greater.

4. The hollow fiber membrane for blood purification according to claim 2 , further comprising: a thickness of a dense layer between 1 and 5 μm.

5. A blood purification apparatus comprising the hollow fiber membrane according to claim 2 , installed in a cylindrical container having two nozzles for flowing a dialysate, the cylindrical container having both ends fabricated with a potting material for separating the hollow inside of the membrane from the outside by a membrane wall and the cylindrical container further having a header cap for flowing blood fitted on both ends.

6. The hollow fiber membrane for blood purification according to claim 1 , wherein an overall mass transfer coefficient of phosphorous is 0.040 cm/min or greater.

7. The hollow fiber membrane for blood purification according to claim 6 , further comprising: a thickness of a dense layer between 1 and 5 μm.

8. A blood purification apparatus comprising the hollow fiber membrane according to claim 6 , installed in a cylindrical container having two nozzles for flowing a dialysate, the cylindrical container having both ends fabricated with a potting material for separating the hollow inside of the membrane from the outside by a membrane wall and the cylindrical container further having a header cap for flowing blood fitted on both ends.

9. The hollow fiber membrane for blood purification according to claim 1 , further comprising: a thickness of a dense layer between 1 and 5 μm.

10. A blood purification apparatus comprising the hollow fiber membrane according to claim 9 , installed in a cylindrical container having two nozzles for flowing a dialysate, the cylindrical container having both ends fabricated with a potting material for separating the hollow inside of the membrane from the outside by a membrane wall and the cylindrical container further having a header cap for flowing blood fitted on both ends.

11. A blood purification apparatus comprising the hollow fiber membrane according to claim 1 , installed in a cylindrical container having two nozzles for flowing a dialysate, the cylindrical container having both ends fabricated with a potting material for separating the hollow inside of the membrane from the outside by a membrane wall and the cylindrical container further having a header cap for flowing blood fitted on both ends.

12. The blood purification apparatus according to claim 11 , wherein the hollow fiber membrane has a phosphorus clearance of at least 180 ml/min per a membrane area of 1.5 m 2 .

13. The follow fiber membrane for blood purification according to claim 1 , wherein the hydrophobic polymer is selected from the group consisting of a polysulfone-based resin, polyether sulfone-based resin, polyamide-based resin, polyimide-based resin, polyphenyl ether-based resin, and polyphenylene sulfide-based resin.

Assignees

• Kuroda Mariko
• Fuke Masaya
• Katou Masaki
• Asahi Kasei Medical Co Ltd

Inventors

• Kuroda Mariko
• Fuke Masaya
• Katou Masaki

Classifications

• A61M1/16 Primary

  with membranes · CPC title

• B01D71/34

  Polyvinylidene fluoride · CPC title

• B01D2325/04

  Characteristic thickness · CPC title

• B01D69/08

  Hollow fibre membranes (manufacture of hollow fibres D01D5/24, D01F1/08) · CPC title

• B01D67/0011

  Casting solutions therefor · CPC title