title: In vivo release of vancomycin from biodegradable beads.
abstract: The current delivery system of antibiotics for the treatment of osteomyelitis uses polymethylmethacrylate (PMMA) beads as a local drug-release agent. The nonbiodegradable nature of the PMMA, however, necessitates a second operation to remove the beads. This article explores the alternative of using biodegradable polymers as antibiotic beads for a long-term drug release in vivo. To manufacture an antibiotic bead, lactide-glycolide copolymers were mixed with vancomycin. The mixture was compressed and sintered at 55 degrees C to form beads 8 mm in diameter. An in vivo animal model was proposed to characterize the elution rate of antibiotic over a 55-day period. Biodegradable beads released high concentrations of antibiotic (well above the breakpoint sensitivity concentration) in vivo for the period of time needed to treat bone infection; that is, 4-6 weeks. A bacterial inhibition test was also carried out to determine the relative activity of the released antibiotics. The diameter of the sample inhibition zone ranged from 8 to 18 mm, which is equivalent to 9.1 to 100% of relative activity. In addition, the antibiotic concentration of systemic blood was found to be very low. Antibiotic-impregnated biodegradable beads may have a potential role in the prevention and management of surgical infections.
authors.affiliation: Department of Mechanical Engineering, Chang Gung University, Tao-Yuan, Taiwan.
authors.forename: Shih-Jung
authors.initials: SJ
authors.lastname: Liu
authors.forename: Steve
authors.initials: S
authors.lastname: Wen-Neng Ueng
authors.forename: Song-Shu
authors.initials: SS
authors.lastname: Lin
authors.forename: Err-Cheng
authors.initials: EC
authors.lastname: Chan
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage* / Q000493:pharmacokinetics; D001672:Biocompatible Materials; D001673:Biodegradation, Environmental; D003692:Delayed-Action Preparations; D016503:Drug Delivery Systems; D004343:Drug Implants; D008422:Materials Testing; D010019:Osteomyelitis / Q000188:drug therapy; D019904:Polymethyl Methacrylate; D011817:Rabbits; D014640:Vancomycin / Q000008:administration & dosage* / Q000493:pharmacokinetics
chemical_list: D000900:Anti-Bacterial Agents; D001672:Biocompatible Materials; D003692:Delayed-Action Preparations; D004343:Drug Implants; D014640:Vancomycin; D019904:Polymethyl Methacrylate