Abstract
A modified water–oil–water double emulsion solvent evaporation method was used to prepare cationic poly (lactic-co-glycolic acid) microspheres. Polyethyleneimine in external water phase was used to stabilize the microspheres and ammonium bicarbonate in internal aqueous phase was adopted to facilitate the formation of pores. It is found that the microspheres with or without pores could be manipulated by easily adjusting the polyethyleneimine concentration. In order to understand the drug delivery potential of the porous microspheres, the model macromolecule agent, fluorescein isothiocyanate–dextran was used. The results show that the porous microspheres obtained by emulsion processing have higher absorption capability compared with non-porous ones. Therefore, the as-obtained porous microspheres could be the suitable platforms for the delivery of bioactive agents.
Fig. 1. CLSM images and fluorescence intensity contours of FITC-DEX - loaded non-porous (a, c), porous PLGA microspheres (b, d), and release profiles of FITC-DEX from porous PLGA microspheres (e).
Kun Fang, Fang Yang, Qiying Zhang, Tianzhu Zhang, Ning Gu, Fabrication of nonporous and porous cationic PLGA microspheres, Materials Letters,http://dx.doi.org/10.1016/j.matlet.2013.11.101