A drug-containing protein-bonded liposome comprising a liposome containing a drug and having maleimide residues on its surface, and a protein and residues of a compound having a polyalkylene glycol moiety, bonded via respective thiol groups to the maleimide residues....http://www.google.es/patents/US5264221?utm_source=gb-gplus-sharePatente US5264221 - Drug-containing protein-bonded liposome
