Influence of PEGylation on the ability of carboxymethyl-dextran to form complexes with α-lactalbumin.

•Poly(ethylene glycol) was attached to reducing end of carboxymethyl-dextran (CMD).•Protein complex formation occurred at pH 5.9 for PEGylated CMD vs. pH 5.5 for CMD.•Phase separation of complexes not influenced by amount of PEGylated CMD.•Spheroidal complexes possessed hydrodynamic radius of 11–40nm.