Morphological and thermal behavior of porous biopolymeric nanoparticles

The aim of the present work is to design, develop and characterize biodegradable polymeric nanoparticles having well defined size and porous morphology. Poly(dl-lactide-co-glycolide) (PLGA) and poly(l-lactide) (PLLA) nanoparticles (NPs) were prepared by double emulsion method with subsequent solvent evaporation. NPs were characterized by electron microscopes, dynamic light scattering, XRD and thermal properties by differential scanning calorimetry and thermogravimetry. Finally, the in vitro degradation analysis was also performed. Biodegradable NPs display a spherical surface structure with a homogeneous size distribution, and an average diameter of 180 nm for PLLA and 218 nm for the PLGA. The NP nanoporous structure was analyzed by an innovative thermal method: thermoporosimetry, providing information about nanopore dimensions. In vitro degradation studies demonstrate the gradual surface aggregation and degradation of NPs and the effects on polymer properties. Biopolymeric porous nano-systems may offer promise properties for revolutionary improvements in tissue engineering, diagnosis and targeted drug delivery systems.