Poly(n-butyl cyanoacrylate) nanoparticles via miniemulsion polymerization (1): Dextran-based surfactants

This study aims at synthesizing polysaccharide-coated poly(n-butyl cyanoacrylate) nanoparticles by miniemulsion polymerization. Because of the high reactivity of n-butyl cyanoacrylate, drastic conditions are required in order to emulsify the monomer in water while limiting its anionic polymerization. However, nanoparticles were successfully obtained by miniemulsion polymerization of butyl cyanoacrylate-in-water emulsions stabilized by amphiphilic dextran derivatives. Their physico-chemical properties were thoroughly investigated as a function of amphiphilic dextran structure and concentration. The substitution degree of the amphiphilic dextran used as stabilizer had little influence on the final properties of the obtained nanoparticles. Particle size decreased with the concentration of amphiphilic dextran in the aqueous phase whereas the hydrophilic layer thickness and the amount of adsorbed polysaccharide were nearly constant in the entire range of concentrations studied.