Conjugation of therapeutic proteins to polymers is well established but most methods result in multi-site and multiple conjugation, or crosslinking resulting in lack of orientation and loss of activity. Using an enzyme mediated conjugation method we have prepared well-defined protein-polymer conjugates using a model protein, green fluorescent protein (eGFP) with diblock & triblock copolymers based on hydrophilic-hydrophobic biocompatible copolymers. In this proposal we wish to determine the effects of altering the block copolymer structures on the properties of aggregates formed by these copolymers conjugates with eGFP in solution, to develop an understanding of the phase behaviour of these species.