?Implications of the synthesis design on Magnetic theranostic systems?

MIRIAM STRUMIA

San Sebastián

Conferencia; 10th ECNP International Conference on Nanostructured Polymers and Nanocomposites; 2018

POLYMAT

Conferencia Invitada al 10th ECNP International Conference on Nanostructured Polymers and Nanocomposites. San Sebastián del 3 al 5 de Octubre de 2018In a previous work, we demonstrated a powerful methodology for the synthesis of MNGs on the basis of an ultrasound-assisted, alkyne-azide strain-promoted cycloaddition as a crosslinking reaction [36]. Magnetic nanoparticles functionalized with bicyclononyne (MNP@BCN) and azidated thermoresponsive linear polyglycerol (tPG) were used as building blocks for synthesizing thermoresponsive MNGs. Spherically shaped MNGs were successfully obtained and decorated with transferrin (Tf) as a model targeting ligand. Its Tf receptor-over expressing CTCs? capturing ability was studied (Figure 1 (figura2 del polymers). The linker length and the number of linkers used to functionalize the targeting protein were very important for optimizing the system. Comparison between PEG linkers with 4, 8, and 12 EG units revealed 8 units as the optimal linker length with the best capturing efficiencies. Moreover, the spacer-to-transferrin ratio played also an important role on the system efficiency. Three linkers per transferrin gave the highest capturing values for all the polymer lengths that reached a top value of 81% for PEG8. Moreover, the use of a bigger thermoresponsive polymer on the construction of the MNG had a negative effect on the capturing ability of the system. The optimal linker-length polymer Tf-system was evaluated in breast-cancer patient blood, and high applicability of this system was estimated in a real scenario. We used MNPs as core, and polyglycerol type polymers with a phase transition temperature of 30°C approximately as thermoresponsive polymer. Then, they were used as drug delivery system with DOX as model drug and their behavior in relation with the temperature was studied. Different nanodevices were obtained with sizes ranging 150-300 nm. The thermoresponsive behavior was fine-tuned by controlling the conditions of synthesis. A comparative study of the behavior of both systems, core-brush and nanogeles, and the potential use of these nansystems for nanomedicine will be presented.