Combination stirrer

Abstract

The present patent application describes a stirrer comprising a combination of at least one axially-conveying element and at least one radially-conveying element relative to the rotary shaft of the stirrer wherein the largest diameter of the at least one axially-conveying element is equal to or less than the inner diameter d i of the radially-conveying element. In one embodiment the stirrer according to the invention is a combination of one anchor stirrer with at least one inclined-blade stirrer. Furthermore the use of the stirrer according to the invention for the culture of cells in a dialysis method is described.

1 . Agitator, comprising
 one radially-conveying element comprising at least two stirrer blades, and   one or more axially-conveying elements each comprising at least two stirrer blades,   wherein the stirrer blades of the radially-conveying element are parallel to each other,   wherein the outer diameter of all axially-conveying elements is equal to or less than the inner diameter of the radially-conveying element,   wherein all axially-conveying elements are individually connected to the radially-conveying element,   wherein all axially-conveying elements are located within the radially-conveying element, and   wherein all conveying elements have a fixed spatial orientation relative to each other.   
     
     
         2 . Agitator according to  claim 1 , characterized in that the number of axially-conveying elements is 1 or 2 or 3. 
     
     
         3 . Agitator according to any one of the previous claims, characterized in that one axially-conveying element is located at a maximum distance of 80% from the top of the blades of the radially-conveying element and/or one axially-conveying element is located at a maximum distance of 20% from the top of the blades of the radially-conveying element. 
     
     
         4 . Agitator according to any one of the previous claims, characterized in that opposing stirrer blades of the radially-conveying element are linked to each other by two opposite stirrer blades of an axially-conveying element. 
     
     
         5 . Agitator according to any one of the previous claims, characterized in that the radially-conveying element is an anchor impeller. 
     
     
         6 . Agitator according to any one of the previous claims, characterized in that the axially-conveying element is an inclined-blade stirrer. 
     
     
         7 . Agitator according to  claim 6 , characterized in that the pitch of the stirrer blades of the inclined-blade stirrer is between 10° and 80° relative to the shaft axis of the agitator. 
     
     
         8 . Agitator according to one of the previous claims, characterized in that the radially-conveying element has 1 to 8 stirrer blades. 
     
     
         9 . Agitator according to one of the previous claims, characterized in that the one or more axially-conveying elements have independent of each other 1 to 10 stirrer blades. 
     
     
         10 . Agitator according to any one of the preceding claims, characterized in that the radially-conveying element has a height of at least 200 mm. 
     
     
         11 . Device comprising an agitator according to any one of  claims 1  to  10  within a cultivation vessel. 
     
     
         12 . Device according to  claim 11 , characterized in further comprising a dialysis module. 
     
     
         13 . Device according to any one of  claims 11  and  12 , characterized in that cultivation vessel is a stirred tank reactor. 
     
     
         14 . Device according to any one of  claims 11  to  13 , characterized in that the cultivation vessel is a submersed gassed stirred tank reactor. 
     
     
         15 . Device according to any one of  claims 11  to  14 , characterized in that the ratio d/D of agitator diameter (d) to cultivation vessel diameter (D) is of from 0.2 to 0.8 
     
     
         16 . Device according to any one of  claims 11  to  15 , characterized in that the ratio H/D of filling height of the cultivation vessel (H) to cultivation vessel width (D) is of from 1.0 to 2.5. 
     
     
         17 . Use of an agitator according to any one of  claims 1  to  10  or a device according to any one of  claims 11  to  16  for cultivating a cell expressing a polypeptide. 
     
     
         18 . Method for the production of a polypeptide comprising
 a) providing a cell comprising a nucleic acid encoding the polypeptide,   b) providing a device as reported herein,   c) cultivating the cell in the device in a cultivation medium wherein the agitator provides a turbulent flow within the cultivation vessel, and   d) recovering the polypeptide from the cells or the cultivation medium and thereby producing a polypeptide.   
     
     
         19 . Use according to  claim 17  or method according to  claim 18 , characterized in that the cultivating is a dialysis. 
     
     
         20 . Use according to any one of  claim 17  or  19  or method according to any one of  claims 18  to  19 , characterized that the cell is a mammalian cell. 
     
     
         21 . Use or method according to  claim 20 , characterized in that the mammalian cell is selected from a CHO cell, a BHK cell, an NS0 cell, a COS cell, a PER.C6 cell, a Sp2/0 cell, or a HEK 293 cell. 
     
     
         22 . Use according to any one of  claims 17  and  19  to  21  or method according to any one of  claims 18  to  21 , characterized in that the polypeptide is an antibody.