title: Collagen/PLGA microparticle composites for local controlled delivery of gentamicin.
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.
authors: Department of Pharmacy, Pharmaceutical Technology and Biopharmaceutics, University of Munich, Butenandtstrasse 5, 81377 Muenchen, Germany.
authors: Monika
authors: M
authors: Schlapp
authors: Wolfgang
authors: W
authors: Friess
mesh_terms: D000900:Anti-Bacterial Agents / Q000008:administration & dosage*; D002498:Centrifugation; D002626:Chemistry, Pharmaceutical; D003094:Collagen; D003692:Delayed-Action Preparations; D005079:Excipients; D005612:Freeze Drying; D005615:Freezing; D005839:Gentamicins / Q000008:administration & dosage*; D006863:Hydrogen-Ion Concentration; D019344:Lactic Acid; D008855:Microscopy, Electron, Scanning; D008863:Microspheres; D008970:Molecular Weight; D010316:Particle Size; D011100:Polyglycolic Acid; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011108:Polymers; D012995:Solubility; D013696:Temperature
chemical_list: D000900:Anti-Bacterial Agents; D003692:Delayed-Action Preparations; D005079:Excipients; D005839:Gentamicins; D011108:Polymers; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; D003094:Collagen