Physicochemical aspects behind the size of biodegradable polymeric nanoparticles: A step forward

Surfactant-free PLGA polymeric nanoparticles (PNPs) with hydrodynamic radius (RH) ranging from 25.8 nm to 128.5 nm were successfully obtained through nanoprecipitation by controlling a variety of physicochemical parameters. The size of the generated PLGA PNPs could be controlled by adjusting the polymer concentration, the choice of organic solvent, mixing different organic solvents or by changing temperature and ionic strength. By optimizing such parameters sub-100 nm uniform PNPs can be produced through this methodology including the advantage and ability to scale-up production. The PNPs have shown a size-dependent effect on the organic solvent and polymer concentration. On the other hand, the polymer–solvent interactions seem not to play a substantial role in the final dimension of the polymer colloids. It has been also evidenced that the size of PNPs can be precisely and linearly tuned by using solvent mixtures as organic phase.