| abstract |
PROBLEM TO BE SOLVED: To provide a substance and a method for complexing a water-soluble polymer with a therapeutic protein. A method for preparing a therapeutic protein complex, wherein (a) a reduced cysteine sulfhydryl group is produced on the therapeutic protein, and (b) a water-soluble polymer is complexed with the reduced cysteine sulfhydryl group. The therapeutic protein comprises contacting the therapeutic protein, or a biologically active fragment thereof, with a thiol reducing agent and the water soluble polymer, or a functional derivative thereof, under conditions that enable the therapeutic protein. , A method having an amino acid sequence having only one accessible cysteine sulfhydryl group. [Selection diagram] None |