Buoyant protein harvesting device

Abstract

A buoyant device containing chromatography media performs the function of protein harvesting replacing the steps of cell separation and volume reduction; the device can be loaded into columns for further purification.

What is claimed is: 
     
         1 . A method for harvesting refolded protein comprising:
 a. providing a protein-harvesting device comprising a porous container with an inner volume comprising a suitable amount of a chromatography media wherein said media is capable of binding a protein and a buoyancy device attached to the porous container;   b. disposing the protein-harvesting device in a container comprising a protein in a refolding solution;   c. adjusting the buoyancy of the protein-harvesting device to a pre-determined level;   d. capturing a refolded protein from the refolding solution with the protein harvesting device;   e. removing the refolding solution;   f. eluting the refolded protein from the chromatography media of the protein harvesting device; and   g. reconstituting the refolded protein eluted from the chromatography media for further purification.   
     
     
         2 . A method for continuous harvesting proteins comprising:
 a. providing a protein-harvesting device comprising a porous container with an inner volume comprising a suitable amount of a chromatography media wherein said media is capable of binding a protein and a buoyancy device attached to the porous container;   b. disposing the protein-harvesting device in a bioreactor comprising a genetically modified organism or cells capable of producing a protein for harvesting in a nutrient media at the beginning of protein production;   c. adjusting the pH and electrolyte concentration of the nutrient media to optimize the binding of the protein to the chromatography media;   d. capturing the protein from the nutrient media continuously throughout; and   e. removing the protein-harvesting device from the nutrient media for further processing of the protein bound to the chromatography media.   
     
     
         3 . A method for continuous harvesting proteins comprising:
 a. providing a protein-harvesting device comprising a porous container with an inner volume comprising a suitable amount of a chromatography media wherein said media is capable of binding a protein and a buoyancy device attached to the porous container;   b. disposing the protein-harvesting device in a bioreactor comprising a genetically modified organism or cells capable of producing a protein for harvesting in a nutrient media at the beginning of protein production;   c. adjusting the pH and electrolyte concentration of the nutrient media to optimize the binding of the protein to the chromatography media;   d. capturing the protein from the nutrient media continuously throughout production of the target protein; and   e. removing the protein-harvesting device from the nutrient media for further processing of the protein bound to the chromatography media.   
     
     
         4 . A method comprising:
 a. continuously removing expressed protein from a nutrient media to enhance the level of expression that may be depressed because of the higher concentration of protein in the mixture;   b. providing a protein-harvesting device comprising a porous container with an inner volume comprising a suitable amount of a chromatography media wherein said media is capable of binding a protein and a buoyancy device attached to the porous container;   c. disposing the protein-harvesting device in a bioreactor comprising a genetically modified organism or cells capable of producing a protein for harvesting in a nutrient media at the beginning of protein production;   d. adjusting the pH and electrolyte concentration of the nutrient media to optimize the binding of the protein to the chromatography media;   e. capturing the protein from the nutrient media continuously throughout; and   f. removing the protein-harvesting device from the nutrient media for further processing of the protein bound to the chromatography media.   
     
     
         5 . A method comprising:
 a. continuously removing expressed protein from a nutrient media to reduce the toxicity of the expressed protein to host cells and thus prolonging the cycles of expression substantially increasing the yields of production;   b. providing a protein-harvesting device comprising a porous container with an inner volume comprising a suitable amount of a chromatography media wherein said media is capable of binding a protein and a buoyancy device attached to the porous container;   c. disposing the protein-harvesting device in a bioreactor comprising a genetically modified organism or cells capable of producing a protein for harvesting in a nutrient media at the beginning of protein production;   d. adjusting the pH and electrolyte concentration of the nutrient media to optimize the binding of the protein to the chromatography media;   e. capturing the protein from the nutrient media continuously throughout; and   f. removing the protein-harvesting device from the nutrient media for further processing of the protein bound to the chromatography media.   
     
     
         6 . A method comprising:
 a. increasing the chemical stability of expressed protein by binding it to a chromatography media as soon as it is expressed as the chemicals are always less stable in a solution form than in a solid form or in this case a complex form;   b. providing a protein-harvesting device comprising a porous container with an inner volume comprising a suitable amount of a chromatography media wherein said media is capable of binding a protein and a buoyancy device attached to the porous container;   c. disposing the protein-harvesting device in a bioreactor comprising a genetically modified organism or cells capable of producing a protein for harvesting in a nutrient media at the beginning of protein production;   d. adjusting the pH and electrolyte concentration of the nutrient media to optimize the binding of the protein to the chromatography media;   e. capturing the protein from the nutrient media continuously throughout; and   f. removing the protein-harvesting device from the nutrient media for further processing of the protein bound to the chromatography media.