title: A novel solvent-free method for the manufacture of biodegradable antibiotic-capsules for a long-term drug release using compression sintering and ultrasonic welding techniques.
abstract: This report was to develop a novel solvent-free method for the manufacture of biodegradable capsules for a long-term drug delivery. To manufacture an antibiotic capsule, polylactide-polyglycolide copolymers were pre-mixed with vancomycin. The mixture was then injection compression molded to form a cylinder with a cover of 8mm in diameter. After the addition of gentamicin sulfate into the core, an ultrasonic welder was used to seal the capsule. An elution method and an high-performance liquid chromatography assay were employed to characterize the in vitro release rates of the antibiotics over a 30-day period. It was found that biodegradable capsules released high concentration of vancomycin and gentamicin (well above the minimum inhibition concentration) in vitro for the period of time needed to treat bone infection; i.e., 2-4 weeks. A bacterial inhibition test was carried out to determine the relative activity of the released antibiotics. The diameter of the sample inhibition zone ranged from 3 to 18 mm, which is equivalent to 16.7-100% of relative activity. By adopting this novel technique, we will be able to manufacture biodegradable capsules of various medicines for long-term drug delivery.
authors.affiliation: Department of Mechanical Engineering, Biomaterials Lab, Chang Gung University, 259, Wen-Hwa 1st Road, Kwei-San, Tao-Yuan 333, Taiwan. shihjung@mail.cgu.edu.tw
authors.forename: Shih-Jung
authors.initials: SJ
authors.lastname: Liu
authors.forename: Ying-E
authors.initials: YE
authors.lastname: Tsai
authors.forename: Steve
authors.initials: S
authors.lastname: Wen-Neng Ueng
authors.forename: Err-Cheng
authors.initials: EC
authors.lastname: Chan
mesh_terms: D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000493:pharmacokinetics* / Q000494:pharmacology; D001673:Biodegradation, Environmental; D003692:Delayed-Action Preparations; D005839:Gentamicins / Q000008:administration & dosage / Q000493:pharmacokinetics* / Q000494:pharmacology; D008826:Microbial Sensitivity Tests; D008855:Microscopy, Electron, Scanning; D012997:Solvents; D014640:Vancomycin / Q000008:administration & dosage / Q000493:pharmacokinetics* / Q000494:pharmacology
chemical_list: D000900:Anti-Bacterial Agents; D003692:Delayed-Action Preparations; D005839:Gentamicins; D012997:Solvents; D014640:Vancomycin