Hollow fiber filter arrangement

1. A hollow fiber filter arrangement comprising:

an inlet for receiving a sample to be filtered in the hollow fiber filter arrangement;

an outlet for delivering the filtered sample out from the hollow fiber filter arrangement;

at least one elongated hollow fiber connected at a first end to the inlet and connected at an opposite second end to the outlet; and

an outer housing enclosing the at least one elongated hollow fiber such that a filtrate collection space substantially surrounds the at least one elongated hollow fiber, wherein the outer housing comprises:

an elongate outer housing part made from a flexible material;

a first end fitment connected to a first end of the elongate outer housing part; and

a second end fitment connected to a second end of the elongate outer housing part;

wherein the first end fitment and the second end fitment each have an elongated boat shape defined by a first curved sidewall and a second curved sidewall connected to one another at opposite ends of the boat shape.

2. The hollow fiber filter arrangement according to claim 1 , wherein the first end fitment comprises the inlet, and wherein the second end fitment comprises the outlet.

3. The hollow fiber filter arrangement according to claim 1 , wherein the elongate outer housing part comprises two flexible sheets which are welded to one another and to each of the first end fitment and the second end fitment.

4. The hollow fiber filter arrangement according to claim 3 , wherein one of the flexible sheets is a wall in a flexible bioreactor bag.

5. The hollow fiber filter arrangement according to claim 1 , wherein the first end fitment and the second end fitment are made from a more rigid material than the elongate outer housing part.

6. The hollow fiber filter arrangement according to claim 1 , wherein the first end fitment comprises a first hollow fiber receiving part configured for holding the first end of the at least one elongated hollow fiber, and wherein the second end fitment comprises a second hollow fiber receiving part configured for holding the second end of the at least one elongated hollow fiber.

7. The hollow fiber filter arrangement according to claim 1 , wherein the at least one elongated hollow fiber is a bundle of elongated hollow fibers provided within a protecting sleeve.

8. The hollow fiber filter arrangement according to claim 1 , wherein the elongate outer housing part comprises a filtrate or waste outlet.

9. The hollow fiber filter arrangement according to claim 1 , wherein the outer housing is sized such that the hollow fiber filter arrangement can be used as a waste bag as well as a filter.

10. The hollow fiber filter arrangement according to claim 1 , wherein the flexible material of the elongate outer housing part is a composite film.

11. The hollow fiber filter arrangement according to claim 1 , wherein the flexible material of the elongate outer housing part comprises ethylene vinyl acetate (EVA), polyethylene vinyl alcohol (PVA), or ultra-low-density polyethylene (LDPE).

12. The hollow fiber filter arrangement according to claim 11 , wherein the first end fitment and the second end fitment are made from polyethylene (PE).

13. The hollow fiber filter arrangement according to claim 1 , further comprising a sleeve surrounding the at least one elongated hollow fiber, wherein the sleeve is made from a more rigid material than the at least one elongated hollow fiber.

14. The hollow fiber filter arrangement according to claim 13 , wherein the first end fitment comprises a first hollow fiber receiving part configured for holding the first end of the at least one elongated hollow fiber and a first end of the sleeve, and wherein the second end fitment comprises a second hollow fiber receiving part configured for holding the second end of the at least one elongated hollow fiber and a second end of the sleeve.

15. A bioreactor system comprising a bioreactor bag suitable for cell culture and the hollow fiber filter arrangement according to claim 1 , wherein the inlet of the hollow fiber filter arrangement is connected to a pump unit which is configured for pumping the cell culture through the hollow fiber filter arrangement for removal of waste from the cell culture.

16. The bioreactor system according to claim 15 , wherein the inlet of the hollow fiber filter arrangement is connected to an outlet of the bioreactor bag via the pump, and wherein the outlet of the hollow fiber filter arrangement is connected to an inlet of the bioreactor bag.

17. The bioreactor system according to claim 15 , wherein the hollow fiber filter arrangement is provided within the bioreactor bag, wherein the inlet of the hollow fiber filter arrangement is connected to an outlet of the bioreactor bag via the pump, and wherein the outlet of the hollow fiber filter arrangement discharges into the bioreactor bag for delivering retained cells into the bioreactor bag.

18. The bioreactor system according to claim 17 , wherein the elongate outer housing part of the hollow fiber filter arrangement comprises a waste outlet connected through a wall of the bioreactor bag to an external waste bag, wherein the elongate outer housing part comprises two flexible sheets welded to each other to enclose the at least one elongated hollow fiber, and wherein one of the flexible sheets is a wall in the bioreactor bag.

19. A cell culture method comprising:

providing a flexible cell culture bioreactor bag;

providing the hollow fiber filter arrangement according to claim 1 within the bioreactor bag; and

culturing cells in the bioreactor bag suspended in a liquid culture medium while rocking the bioreactor bag.

20. The cell culture method according to claim 19 , further comprising repeatedly or continuously passing the suspension through the hollow fiber filter arrangement.