Preparation, characterization and in vitro drug release studies of novel polymeric nanoparticles

Polymeric nanoparticles of AADG cross-linked with MBA encapsulating water soluble macromolecules such as FITC-Dextran have been prepared in the reverse micellar system. The particles obtained were of >85 nm in diameter which were highly monodisperse. An optically clear solution was obtained on redispersing these nanoparticles in aqueous buffer. Size and morphology of the particles remains the same on re-dispersing the lyophilized powder of these nanoparticles in aqueous buffer. The size dependency of the particles on the monomer and surfactant concentration was observed. The average size of the nanoparticles as obtained from DLS studies ranges from 74 to 114 nm in case 0.06 M AOT and 62–104 nm in case of 0.1 M AOT concentration. FITC-Dextran was entrapped into nanoparticles with high efficiency (>70%). The pH dependent release of the entrapped molecules from these nanoparticles was also studied. At pH 5.0 solution, ∼43% of FITC-Dx was released and at pH 7.4 it was about 70%.