Preparation and evaluation of chitosan nanoparticles for neutron-capture therapy by a novel emulsion-droplet coalescence technique

Chitosan nanoparticle with Gd (Gd-nano-CP) was developed. The effects of preparation conditions on the properties were investigated and in vivo Gd-NCR test was carried out. Effects of Gd dose on tumor growth inhibition against C3H/He mice bearing s.c.SCC-7 cells by Gd-NCT showed good inhibition effect by 900 μg/tumor or more dose. Nano-CP showed 1) the strong interaction could uptake the high concentration of acid substance, 2) the small particle size (426-750 nm) made large diffusion in the tumor cell, 3) the compound could diffuse in order to decrease the interaction between chitosan and the internal compound by interstitial fluid and 4) the particle with positive surface became a carrier that made possible uptake particle into the tumor cell. (S.Y.)