Controlling the morphology of polycaprolactone microparticles produced by electrospraying

Abstract

Electrospraying is an effective method to produce polycaprolactone microparticles for drug or protein carrier application. In this study, some factors which influenced the morphology of polycaprolactone (PCL) particles were investigated by Scanning Electron Microscopy (SEM), such as polymer concentration, solvent and distance from tip to the collector. The SEM micrographs indicated that the low concentration (1 %) of PCL solution created in wrinkled and hollow semi-spheres while wrinkled spheres were formed by using higher polymer concentration (4 %). The spherical morphology was obtained when the polymer concentration was high enough (4 %) to create significant chain entanglements. In addition, chloroform and dichloromethane were good solvents to fabricate electrosprayed microspheres. Solvent mixtures such as acetone and chloroform or Dimethylformamide (DMF) and chloroform were unsuitable for electrosprayed particles since they caused unstable and heterogeneous shape. This research demonstrated that the morphology of microparticles was controlled by adjusting parameters of electrospraying to have a homogeneous and stable morphology.