Method for purifying protein
AssigneeAsahi Kasei Chemicals Corporation
InventorsYuta Sato, Naoyuki Shinohara, Hironobu Shirataki
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Abstract
It is an object of the present invention to provide a method for eluting an adsorbed protein that suppresses a decrease in protein adsorption ability, in a method for purifying a protein using a protein-adsorbing porous membrane. The present invention provides a method for purifying a protein, comprising an adsorption step and an elution step, wherein in the elution step, at least one eluent is passed in the opposite direction with respect to the direction of the passage of a stock solution containing an adsorption target protein, in the adsorption step.
Claims16
A method for purifying a protein by a porous membrane having a substrate surface coated with a polymer having protein adsorption ability, comprising:
- an adsorption step of passing a stock solution containing an adsorption target protein through a pore direction from one surface to another surface of the porous membrane to allow the polymer to adsorb the adsorption target protein;
- and
- an elution step of passing an eluent through the porous membrane to allow the adsorption target protein that is adsorbed on the polymer to elute in the eluent,
- wherein in the elution step, at least one eluent is passed in an opposite direction with respect to the pore direction of passage of the stock solution in the adsorption step;
- wherein a degree of multilayering of the porous membrane is 1.1 or more, and the degree of multilayering is a value obtained by the following formula (3)
- degree of multilayering=(equilibrium adsorption capacity)/(theoretical single-layer adsorption capacity) (3)
- where the equilibrium adsorption capacity is obtained by the following formula (4), when the stock solution comprising the adsorption target protein is passed through the porous membrane
- equilibrium
-
-
- adsorption
-
-
- capacity
-
- [
-
- g
- -
- amount
-
-
- of
-
-
- adsorption
-
- /
- g
- -
- membrane
- ]
- =
- ∫
- 0
- Q
- e
-
- (
- C
- 0
- -
- C
- )
-
- ⅆ
- Q
- W
- (
- 4
- )
- where C0:
- concentration of protein in stock solution [g/L];
- C:
- protein concentration in passed solution of stock solution [g/L];
- Q:
- cumulative amount of passed solution of stock solution [L];
- Qe:
- amount of passed solution of stock solution when adsorption equilibrium is reached [L];
- W:
- weight of protein-adsorbing porous membrane [g];
- and
- the theoretical single-layer adsorption capacity is obtained by the following formula (5)
- theoretical single-layer adsorption capacity[g−amount of single-layer adsorption/g−membrane]=(SM/SP)(Mr/NA) (5)
- where SM:
- specific surface area of protein-adsorbing porous membrane [m2/g];
- SP:
- area occupied by one protein molecule [m2];
- Mr:
- molecular weight of BSA [g/mol];
- and
- NA:
- Avogadro's number [/mol].
Dependencies are inferred from the claim text.