Thermosensitive liposomes entrapping iron oxide nanoparticles for controllable drug release.
Iron oxide nanoparticles can serve as a heating source upon alternative magnetic field (AMF) exposure. Iron oxide nanoparticles can be mixed with thermosensitive nanovehicles for hyperthermia-induced drug release, yet such a design and mechanism may not be suitable for controllable drug release applications in which the tissues are susceptible to environmental temperature change such as brain tissue. In the present study, iron oxide nanoparticles were entrapped inside of thermosensitive liposomes for AMF-induced drug release while the environmental temperature was maintained at a constant level. Carboxyfluorescein was co-entrapped with the iron oxide nanoparticles in the liposomes as a model compound for monitoring drug release and environmental temperature was maintained with a water circulator jacket. These experiments have been successfully performed in solution, in phantom and in anesthetized animals. Furthermore, the thermosensitive liposomes were administered into rat forearm skeletal muscle, and the release of carboxylfluorescein triggered by the external alternative magnetic field was monitored by an implanted microdialysis perfusion probe with an on-line laser-induced fluorescence detector. In the future such a device could be applied to simultaneous magnetic resonance imaging and non-invasive drug release in temperature-sensitive applications.
Center for Nanomedicine Research, National Health Research Institutes, Zhunan 350, Taiwan.
Lin-Ai
LA
Tai
Pi-Ju
PJ
Tsai
Yu-Chao
YC
Wang
Yu-Jing
YJ
Wang
Leu-Wei
LW
Lo
Chung-Shi
CS
Yang
D000818:Animals; D003692:Delayed-Action Preparations / Q000737:chemistry*; D004574:Electromagnetic Fields; D004867:Equipment Design; D005290:Ferric Compounds / Q000737:chemistry*; D005452:Fluoresceins / Q000737:chemistry; D008081:Liposomes / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D046529:Microscopy, Electron, Transmission; D051381:Rats; D013696:Temperature
D003692:Delayed-Action Preparations; D005290:Ferric Compounds; D005452:Fluoresceins; D008081:Liposomes; C000499:ferric oxide; C024098:6-carboxyfluorescein