A phospholipid-protein hybrid nanostructure was found to reveal various hydrodynamic diameters dependent on the amount of the drugs incorporated, which could be over 10 times larger than that of the starting nanostructure. This observation was likely related to the thermal stabilization of the nanostructure during incorporation of the drugs by using the increased amount of phospholipids for the preparation. Furthermore, hydrophobicity or molecular weight of drugs is at least needed for size control.