Optimization of Magneto-thermally Controlled Release Kinetics by Tuning of Magnetoliposome Composition and Structure.

Stealth (PEGylated) liposomes have taken a central role in drug formulation and delivery combining efficient transport with low nonspecific interactions. Controlling rapid release at a certain location and time remains a challenge dependent on environmental factors. We demonstrate a highly efficient and scalable way to produce liposomes of any lipid composition containing homogeneously dispersed monodisperse superparamagnetic iron oxide nanoparticles in the membrane interior. We investigate the effect of lipid composition, particle concentration and magnetic field actuation on colloidal stability, magneto-thermally actuated release and passive release rates. We show that the rate and amount of encapsulated hydrophilic compound released by actuation using alternating magnetic fields can be precisely controlled from stealth liposomes with high membrane melting temperature. Extraordinarily low passive release and temperature sensitivity at body temperature makes this a promising encapsulation and external-trigger-on-demand release system. The introduced feature can be used as an add-on to existing stealth liposome drug delivery technology.