Chong S Chang

US Patent:

52506622, Oct 5, 1993

Filed:

Feb 27, 1992

Appl. No.:

7/842749

Inventors:

Chong E. Chang - La Canada CA

Assignee:

Alpha Therapeutic Corporation - Los Angeles CA

International Classification:

C07K 322
C07K 1506

US Classification:

530364

Abstract:

There is provided in accordance with the practice of this invention a process for separating albumin from an impure protein fraction containing albumin. Contaminants, in an aqueous solution of the impure protein fraction containing albumin, are precipitated from the solution at a pH of from about 4. 5 to about 4. 7. Additional contaminants that remain soluble are bound to an anion-exchange resin. After the precipitated and anion-exchange-bound contaminants are removed from the albumin-containing solution, the pH of the solution is adjusted to from about 4. 7 to about 6. 1, and additional contaminants are precipitated. Further contaminants are then bound to an anion-exchange resin, and these precipitated and anion-exchange-bound contaminants are removed from the albumin-containing solution.

US Patent:

46247807, Nov 25, 1986

Filed:

Apr 19, 1984

Appl. No.:

6/601841

Inventors:

Chong E. Chang - La Canada CA

Assignee:

Alpha Therapeutic Corporation - Los Angeles CA

International Classification:

B01D 3600

US Classification:

2101951

Abstract:

There is provided in accordance with practice of this invention a process for separating protein fractions from a solution containing proteins and an apparatus for practicing the process. The process and apparatus involve withdrawing from a suspension tank a portion of the suspension contained therein to form a recycle stream. The withdrawn suspension forming the recycle stream contains particles of a selected protein fraction precipitated from a solution containing proteins. Fresh protein solution comprising proteins of the selected protein fraction is mixed into the recycle stream to form a mixed recycle stream. At least a portion of the selected protein fraction proteins in the fresh protein solution precipitate onto previously precipitated selected protein fraction particles suspended in the mixed recycle stream. The mixed recycle stream is introduced back into the suspension tank. A portion of the suspension is withdrawn from the suspension tank in a product stream and precipitated, selected protein fraction particles are recovered from the product stream.

US Patent:

44863411, Dec 4, 1984

Filed:

Jun 28, 1982

Appl. No.:

6/393030

Inventors:

Chong E. Chang - La Canada CA

Assignee:

Alpha Therapeutic Corporation - Los Angeles CA

International Classification:

C07G 700

US Classification:

260112B

Abstract:

There is provided in accordance with practice of this invention a process for separating protein fractions from a solution containing proteins and an apparatus for practicing the process. The process and apparatus involve withdrawing from a suspension tank a portion of the suspension contained therein to form a recycle stream. The withdrawn suspension forming the recycle stream contains particles of a selected protein fraction precipitated from a solution containing proteins. Fresh protein solution comprising proteins of the selected protein fraction is mixed into the recycle stream to form a mixed recycle stream. At least a portion of the selected protein fraction proteins in the fresh protein solution precipitate onto previously precipitated selected protein fraction particles suspended in the mixed recycle stream. The mixed recycle stream is introduced back into the suspension tank. A portion of the suspension is withdrawn from the suspension tank in a product stream and precipitated, selected protein fraction particles are recovered from the product stream.