Table of Contents
ISRN Polymer Science
Volume 2014, Article ID 128154, 6 pages
Research Article

Preparation and Drug-Release Kinetics of Porous Poly(L-lactic acid)/Rifampicin Blend Particles

Department of Materials Science and Engineering, University of Fukui, 3-9-1 Bunkyo, Fukui 910 8507, Japan

Received 29 November 2013; Accepted 18 January 2014; Published 23 February 2014

Academic Editors: C. Bernal, A. Granville, D. Pavel, J. Puiggali, A. V. Raghu, A. Uygun, and A. Varesano

Copyright © 2014 Takashi Sasaki et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Porous polymer spheres are promising materials as carriers for controlled drug release. As a new drug-carrier material, blend particles composed of poly(L-lactic acid) (PLLA) and rifampicin were developed using the freeze-drying technique. The blend particles exhibit high porosity with a specific surface area of 10–40 m2 g−1. Both the size and porosity of the particles depend on the concentration of the original solution and on the method of freezing. With respect to the latter, we used the drop method (pouring the original solution dropwise into liquid nitrogen) and the spray method (freezing a mist of the original solution). The release kinetics of rifampicin from the blend particles into water depends significantly on the morphology of the blend particles. The results show that the release rate can be controlled to a great extent by tuning the size and porosity of the blend particles, both of which are varied by parameters such as the solution concentration and the method of freezing.