title: Controlled release of gentamicin from calcium phosphate-poly(lactic acid-co-glycolic acid) composite bone cement.
abstract: Modification of a self setting bone cement with biodegradable microspheres to achieve controlled local release of antibiotics without compromising mechanical properties was investigated. Different biodegradable microsphere batches were prepared from poly(lactic-co-glycolic acid) (PLGA) using a spray-drying technique to encapsulate gentamicin crobefate varying PLGA composition and drug loading. Microsphere properties such as surface morphology, particle size and antibiotic drug release profiles were characterized. Microspheres were mixed with an apatitic calcium phosphate bone cement to generate an antibiotic drug delivery system for treatment of bone defects. All batches of cement/microsphere composites showed an unchanged compressive strength of 60 MPa and no increase in setting time. Antibiotic release increased with increasing drug loading of the microspheres up to 30% (w/w). Drug burst of gentamicin crobefate in the microspheres was abolished in cement/microsphere composites yielding nearly zero order release profiles. Modification of calcium phosphate cements using biodegradable microspheres proved to be an efficient drug delivery system allowing a broad range of 10-30% drug loading with uncompromised mechanical properties.
authors.affiliation: Department of Pharmaceutics and Biopharmacy, Philipps-University Marburg, Ketzerbach 63, 35032 Marburg, Germany.
authors.forename: Julia
authors.initials: J
authors.lastname: Schnieders
authors.forename: Uwe
authors.initials: U
authors.lastname: Gbureck
authors.forename: Roger
authors.initials: R
authors.lastname: Thull
authors.forename: Thomas
authors.initials: T
authors.lastname: Kissel
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage*; D018786:Bone Substitutes; D002130:Calcium Phosphates; D045744:Cell Line, Tumor; D016503:Drug Delivery Systems; D005839:Gentamicins / Q000008:administration & dosage*; D019344:Lactic Acid; D051379:Mice; D008863:Microspheres; D011100:Polyglycolic Acid; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011108:Polymers
chemical_list: D000900:Anti-Bacterial Agents; D018786:Bone Substitutes; D002130:Calcium Phosphates; D005839:Gentamicins; D011108:Polymers; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; C020243:calcium phosphate