Flexible film in single use bioreactor
A container, such as a disposable or single use bioreactor, optionally having one or more inlets and one or more outlets and a mixer associated with the container to cause mixing, dispersing, homogenizing and/or circulation of one or more ingredients contained or added to the container. The container includes a flexible baffle shaped and positioned within the container to improve mixing, particularly to improve low shear mixing. The baffle is positioned within the container so as to disrupt the vortex formed by the mixer, or prevent formation of a vortex. The baffle is shaped with both horizontal and vertical elements to enhance disruption of the vortex across the entire vessel height and provide homogeneous mixing throughout all operating volumes. In certain embodiments, the baffle is X-shaped.
1. A container for a fluid, comprising:
a volume formed of a flexible material, the volume defined by a base, a top and at least one side connecting said top to said base, one or more inlets in said container, one or more outlets in said container, a fluid in said container having a fluid surface, an impeller assembly mounted at least partially within said volume of said container, said container having a height, and a flexible baffle in said volume of said container, said baffle being X-shaped when said container is viewed in cross-section from said top to said base, said X-shaped baffle being positioned in said container so as to have a horizontal and a vertical component in said container, said X-shaped baffle formed of two legs, each of said legs extending from a lower portion of said container to an upper portion of said container so as to form a diagonal with respect to the horizontal and slicing through said fluid surface and being only partially submerged in said fluid so as to enhance disruption of a vortex across the entire container height during operation of said impeller assembly to mix said fluid.
2. The container of claim 1 , wherein said volume is a closed volume.
3. The container of claim 1 , wherein said container is bioreactor.
4. The container of claim 1 , wherein said fluid comprises cells.
5. The container of claim 4 , wherein said fluid further comprises microcarriers for said cells.
6. The container of claim 1 , wherein said container has an internal wall, and wherein said baffle extends to said internal wall.
7. The container of claim 1 , wherein said baffle has a thickness that is related to said volume of said container by the relationship: baffle thickness (inches)=0.0006*(tank volume (liters)+0.9098.
8. The container of claim 1 , wherein said baffle has a surface area that is related to said volume of said container by the relationship: baffle surface area (square inches)=0.1601*(tank volume (liters)+33.869.
9. A method of mixing a fluid in a container, comprising:
providing a container defining a volume and having a height, the volume defined by a base, a top and at least one side connecting said top to said base;
providing an impeller assembly mounted at least partially within said volume of said container;
positioning a flexible baffle in said volume of said container so as to have a horizontal and a vertical component in said container; said baffle being X-shaped when said container is viewed in cross-section from said top to said base, said X-shaped baffle formed of two legs, each of said legs extending from a lower portion of said container to an upper portion of said container so as to form a diagonal with respect to the horizontal,
introducing fluid to be mixed into said container to a level only partially submerging said baffle, thereby defining a fluid surface, wherein each of said legs slices slicing through said fluid surface; and
driving said impeller assembly to mix said fluid;
whereby said baffle minimizes the formation of any vortex across the entire container height during said mixing.
10. The method of claim 9 , wherein said container is a bioreactor.
11. The method of claim 9 , wherein said fluid comprises cells.
12. The method of claim 11 , wherein said fluid further comprises microcarriers for said cells.
13. The method of claim 9 , wherein said container has an internal wall, and wherein said baffle is positioned in said volume of said container to extend to said internal wall.
14. The method of claim 9 , wherein said baffle has a thickness that is related to said volume of said container by the relationship: baffle thickness (inches)=0.0006*(tank volume (liters)+0.9098.
15. The method of claim 9 , wherein said baffle has a surface area that is related to said volume of said container by the relationship: baffle surface area (square inches)=0.1601*(tank volume (liters)+33.869.