| abstract |
A PEG bound polypeptide comprising one or two unique variable domains of antibody, wherein the polypeptide has a hydrodynamic size of at least 200 kDa and a total PEG size of 20 to 60 kDa, in which the hydrodynamic size is determined using a Superose 6 HR or 12 HR gel chromatography column, a polypeptide concentration of 1.5 mg / ml, and a flow rate of 0.5 ml / min; and wherein each variable domain comprises a framework region and has an antigen binding site, and each variable domain fixes the antigen as a unique variable domain of antibody in the polypeptide and, additionally, in which said PEG is present as one or multiple molecules bound to the polypeptide through an amino acid residue in the framework regions of said one or two unique variable domains of antibody. |