Doxorubicin Loaded Magnetic Polymersomes: Theranostic Nanocarriers for MR Imaging and Magneto-Chemotherapy

Hydrophobically modified magnetic nanoparticles (MNPs) were encapsulated within the membrane of poly(trimethylene carbonate)-b-poly(L-glutamic acid) (PTMC-b-PGA) block copolymer vesicles using a nanoprecipitation process. This formulation method provides a high loading of MNPs (up to 70 wt %) together with a good control over the sizes of the vesicles (100 - 400 nm). The deformation of the vesicle membrane under an applied magnetic field was evidenced by anisotropic SANS. These hybrid objects display contrast enhancement properties in Magnetic Resonance Imaging, a diagnostic method routinely used for three-dimensional and non-invasive scans of the human body. They can also be guided in a magnetic field gradient. The feasibility of drug release triggered by magnetic induction was evidenced using the anticancer drug doxorubicin (DOX), which is co-encapsulated in the membrane. Magnetic polymersomes are thus proposed as multimodal drug nanocarriers for bio-imaging and magneto-chemotherapy.FP7 CP-IP 213631-2 NANOTHE

Noninvasive imaging of nanomedicines and nanotheranostics: principles, progress, and prospects

Noninvasive imaging is used for many different (pre)clinical purposes, ranging from disease diagnosis, disease staging, and treatment monitoring to the visualization and quantification of nanomedicine-mediated drug targeting and (triggered) drug release. Noninvasive imaging can be employed to visualize and quantify how efficient passive or active drug targeting is in individual patients and, on this basis, to preselect patients likely to respond to nanomedicine-based chemotherapeutic interventions. In addition, it can be used to visualize the off-target localization of nanomedicines, e.g., in potentially endangered healthy tissues, which under certain circumstances might lead to exclusion from targeted treatment. Moreover, by systematically integrating imaging also during follow-up and by closely monitoring therapeutic responses upon nanomedicine treatment, clinical decision making can be facilitated and improved, as decisions on whether or not to (dis)continue treatment and on whether or not to adjust drug doses can be made relatively early on. Noninvasive imaging may be particularly useful in the case of metastatic disease. By subsequently performing PET or SPECT scans with radionuclide-labeled nanomedicines, information can be obtained on the accumulation of these formulations in both primary tumors and metastases, and treatment protocols can be adapted accordingly