Synthesis of reductive responsive polyphosphazenes and their fabrication of nanocarriers for drug delivery application

Reductive responsive nanovehicles have the ability to deliver the anticancer drugs to intracellular compartments. The purpose of this study was to develop reductive sensitive nanocarriers based on polyphosphazenes. Amphiphilic polyphosphazenes with hydrophilic reductive sensitive side group and different molecular weights were synthesized and characterized. The synthesized copolymers show solvent dependent self-aggregation and form spherical micelles by using THF as co-organic solvent in dialysis method with critical micelle concentration value ranging from 5.73 mu g/mL to 11.24 mu g/mL. Micelles can encapsulate the hydrophobic drugs such as camptothecin (CPT) and indomethacin. In in vitro release experiments, CPT-loaded micelles release 70-80% of the loaded CPT in the presence of reducing agent dithiothreitol within 15h. The results indicate that these reductive sensitive amphiphilic polyphosphazenes may find an application as anticancer drug carriers for safe drug delivery.