Alginate microgels loaded with temperature sensitive liposomes for magnetic resonance imageable drug release and microgel visualization

摘要

The objective of this study was to prepare and characterize alginate microgels loaded with temperature sensitive liposomes, which release their payload after mild hyperthermia. It is further aimed that by using these microgels both the drug release and the microgel deposition can be visualized by magnetic resonance imaging (MRI) after their administration (e.g. in the vicinity of a tumor). To this end, temperature sensitive (TSL) and non-temperature sensitive liposomes (NTSL) loaded with fluorescein (drug mimicking dye) and a T-1 MRI contrast agent (Prohance,(R)[Gd(HPDO3A)(H2O)]) were encapsulated in alginate microgels crosslinked by holmium ions (73 MRI contrast agent). The drug release could be monitored by the release of [Gd(HPDO3A)(H2O)] while the microgels could be visualized using MRI via the holmium ions in the microgels. The microgels were prepared with a JetCutter and had an average size of 325 mu m and contained similar to 0.6 wt% Ho3+.