UV Cross-Linked Redox-Responsive Hydrogels for Co-Delivery of Hydrophilic and Hydrophobic Drugs

A novel redox-responsive hydrogel was designed for the co-encapsulation and controlled release of hydrophilic and hydrophobic drugs, using 5-fluorouracil (5-FU) and camptothecin (CPT) as the model drugs, respectively. For this purpose, Pluronic F-127 diacrylate macromer was synthesized and then self-assembled into the micelles with their hydrophobic cores loading CPT. The CPT-loaded micelles were then mixed with 5-FU, N,N-bis(acryloyl)cystamine and photoinitiator to form the redox-responsive hydrogels rapidly under a low intensity UV light. The gelation time and strength properties of the obtained hydrogels were studied by rheological tests. The swelling and degradation properties were tested with the rheometer and scanning electron microscope. For the co-encapsulated CPT and 5-FU, their controlled and sustained release as well as the cytotoxicity to tumor cells was also evaluated.