Collagen/PLGA microparticle composites for local controlled delivery of gentamicin

Collagen/PLGA microparticle composites for local controlled delivery of gentamicin
Published Online: 26 Aug 2003
Received: 1 August 2002; Revised: 14 April 2003; Accepted: 14 April 2003
Monika Schlapp, Wolfgang Friess *
Journal of Pharmaceutical Sciences
Volume 92, Issue 11 , Pages 2145 - 2151
Wiley InterScience
Department of Pharmacy, Pharmaceutical Technology and Biopharmaceutics, University of Munich, Butenandtstrasse 5, 81377 Muenchen, Germany

email: Wolfgang Friess (friess@lrz.uni-meunchen.de)
*Correspondence to Wolfgang Friess, Department of Pharmacy, Pharmaceutical Technology and Biopharmaceutics, University of Munich, Butenandtstrasse 5, 81377 Muenchen, Germany. Telephone: 0049-89-218077017; Fax: 0049-89-218077020
Keywords
microparticles ? gentamicin ? PLGA ? collagen ? lyophilization
Abstract
To preserve the positive effect of collagen on tissue regeneration and to locally deliver low molecular weight compounds for an extended time period, a composite for parenteral application was devised based on a collagen sponge with gentamicin-loaded PLGA microparticles incorporated. Antibiotic liberation from the particles was sustained over 1 week by blending two PLGA polymers. Homogenous incorporation of the microspheres in the porous carrier could be realized by lyophilization of a particle suspension in the aqueous collagen preparation. Particle loss upon incubation was reduced with higher collagen concentration enabling local particle retention after application. Lower freezing rate and longer exposure of the PLGA microparticles to the acidic collagen dispersion at temperatures below the glass transition temperature resulted in an increase of the gentamicin burst. The final implant containing both nonencapsulated gentamicin and an equivalent amount incorporated in the microparticles reflected the microbiological demands and exhibited liberation of a high gentamicin dose initially and subsequently extended antibiotic liberation for about one week. ? 2003 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 92:2145-2151, 2003