Preparation of nanodispersions containing β-carotene by solvent displacement method

The aim of this study is to produce β-carotene-loaded nanodispersions containing poly(d,l-lactic acid) (PLA) and poly(d,l-lactic-co-glycolic acid) (PLGA), that are widely used as polymer carriers, by solvent displacement method. Nanoparticles containing β-carotene were produced by interfacial deposition of the biodegradable polymer, due to the displacement of acetone from the dispersed phase. Gelatin or Tween® 20 was used as stabilizing hydrocolloids in the continuous phase. β-carotene was entrapped in the polymeric matrix in the absence of any oily core material. In this kind of formulation, polymers assumed the function of protective colloids and possibly also chemical stabilization of the nanodispersed phase. For measuring the total β-carotene concentration of nanodispersions, β-carotene was extracted from the nanoparticles and analyzed spectrophotometrically. Analysis of the nanoparticle size and its distribution were carried out by laser diffraction spectrometry with polarization intensity differential scattering (PIDS) technology. Morphological examination of nanoparticles was performed by transmission electron microscopy (TEM). In all conditions, the β-carotene-enriched nanoparticles had a narrow size distribution.