Purpose: The thermosensitive micelles based on the poly(PEG:CPP:SA) terpolymer composed of poly(ethylene glycol) (PEG), 1,3-bis(carboxyphenoxy) propane (CPP) and sebacic acid (SA) were fabricated for application as a promising drug carrier.
Methods: The terpolymer can self-assemble into micelles in water by a precipitation technology. The sol-gel transition behaviors were investigated by the tube-tilting method and dynamic rheology. The drug release behaviors were investigated in phosphate-buffered solution (PBS) at 25, 37 and 45 degrees C, respectively, and the tumor cell growth inhibition assays were also evaluated.
Results: The diameters of these micelles increased as the environmental temperature, and the length of CPP and SA chains increased. The micelles with a low concentration underwent sol-to-nanogel transition as temperature increased from the room temperature to the body temperature, while the polymer solutions with a high concentration underwent sol-to-gel transition as the temperature increased from 20 to 70 degrees C. In vitro release profiles consisted of a burst release followed a sustained release. The cytotoxicity results showed that the terpolymer micelles were biocompatible, and the encapsulated doxorubicin. HCl maintained its potent anti-tumor effect.
Conclusion: These micelles may bring the ether-anhydride family of polymers great potential as a novel carrier in nanomedicine.