N-isopropylacrylamide copolymers for the preparation of pH-sensitive liposomes and polymeric micelles
| Autor: | Emmanuelle Roux, Dorothée Le Garrec, Keelung Hong, Jean-Christophe Leroux, Daryl C. Drummond |
|---|---|
| Rok vydání: | 2001 |
| Předmět: |
Acrylate polymer
Indoles Polymers Population Pharmaceutical Science Polyethylene glycol Isoindoles Micelle Pyranine Mice chemistry.chemical_compound Amphiphile Polymer chemistry Tumor Cells Cultured Animals Organic chemistry Colloids Particle Size education Micelles Acrylamides Drug Carriers Liposome education.field_of_study Photosensitizing Agents Hydrogen-Ion Concentration Molecular Weight Solubility chemistry Liposomes Drug carrier Porosity |
| Zdroj: | Journal of Controlled Release. 72:71-84 |
| ISSN: | 0168-3659 |
| DOI: | 10.1016/s0168-3659(01)00263-2 |
| Popis: | Hydrophobically-modified copolymers of N-isopropylacrylamide bearing a pH-sensitive moiety were investigated for the preparation of pH-responsive liposomes and polymeric micelles. The copolymers having the hydrophobic anchor randomly distributed within the polymeric chain were found to more efficiently destabilize egg phosphatidylcholine (EPC)/cholesterol liposomes than the alkyl terminated polymers. Release of both a highly-water soluble fluorescent contents marker, pyranine, and an amphipathic cytotoxic anti-cancer drug, doxorubicin, from copolymer-modified liposomes was shown to be dependent on pH, the concentration of copolymer, the presence of other polymers such as polyethylene glycol, and the method of preparation. Both polymers were able to partially stabilize EPC liposomes in human serum. These polymers were found to self-assemble to form micelles. The critical association concentration was low (9--34 mg/l) and influenced by the position of the alkyl chains. In phosphate buffered saline, the micelles had a bimodal size distribution with the predominant population having a mean diameter of 35 nm. The polymeric micelles were studied as a delivery system for the photosensitizer aluminum chloride phthalocyanine, (AlClPc), currently evaluated in photodynamic therapy. pH-Responsive polymeric micelles loaded with AlClPc were found to exhibit increased cytotoxicity against EMT-6 mouse mammary cells in vitro than the control Cremophor EL formulation. |
| Databáze: | OpenAIRE |
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