Designed Boron-Rich Polymeric Nanoparticles Based On Nano-Ion Pairing For Boron Delivery

Boron-rich particles with the boron fraction ca.10-20 wt % of controllable shape and size that can be easily prepared via simple ion co-assembly are promising material for tumor treatment by boron neutron capture therapy. Electroneutral, dynamic core-shell polymeric nanoparticles were prepared by co-assembly of cationic PEO-block-PGEA diblock copolymer with sodiumcloso-dodecaborate, Na-2[B12H12]. This is the first example of polymer nanoparticles based on [B12H12](2-)nano-ion pairing. The high [B12H12](2-)loading is proven by calorimetry at physiological salt concentration. As a result of rational design, rod-, worm- and sphere-like particles were produced and further tested using human glioblastoma and cervical carcinoma cell lines. Rod-like particles yielded the highest internalization capability in all tested cell lines.