title: Effect of zein on biodegradable inserts for the delivery of tetracycline within periodontal pockets.
abstract: Treatment with antibiotics within the periodontal pocket against bacterial infections represents a useful and adjunctive tool to conventional therapy for healing and teeth preservation. With this function in view, an implantable, tetracycline delivery device for the treatment of periodontal disease was developed. The aim of this study was to develop biodegradable, tetracycline-loaded microparticles made of two polymers: PLGA and zein which were compressed into monolithic devices. In this polymer delivery system, the encapsulation efficiency, release characteristics, drug-polymer interaction, and antibacterial activity of loaded drug were investigated. The interaction of tetracycline with the corn protein zein was studied by nuclear magnetic resonance (NMR), Fourier transform infrared, and X-ray diffraction. The hydrophobic interaction of tetracycline with zein in the formulations was deduced from the NMR studies, whereas X-ray diffraction studies showed a new crystalline state of the drug in the presence of the protein. Zein was not denatured by preparation of inserts. Sustained release of tetracycline was obtained, and the proportion of zein in the inserts had a great impact on the drug release. Finally, an effective tetracycline release from inserts against Staphylococcus aureus was achieved over 30 days. In conclusion, the PLGA:zein delivery system described in this study was found to be effective in controlled delivery of tetracycline, and hence may be suitable for intra-pocket delivery of antimicrobial agents in the treatment of periodontitis.
authors.affiliation: The Capes Foundation, Ministry of Education of Brazil, Cx. Postal 365, Brasília DF 70359-970, Brazil.
authors.forename: Fábio Oliveira
authors.initials: FO
authors.lastname: de Sousa
authors.forename: Jose
authors.initials: J
authors.lastname: Blanco-Méndez
authors.forename: Antonio
authors.initials: A
authors.lastname: Pérez-Estévez
authors.forename: Rafael
authors.initials: R
authors.lastname: Seoane-Prado
authors.forename: Asteria
authors.initials: A
authors.lastname: Luzardo-Álvarez
mesh_terms: D020341:Absorbable Implants; D000900:Anti-Bacterial Agents / Q000008:administration & dosage* / Q000494:pharmacology; D016503:Drug Delivery Systems / Q000295:instrumentation*; D006801:Humans; D019344:Lactic Acid / Q000737:chemistry; D019906:Nuclear Magnetic Resonance, Biomolecular; D010514:Periodontal Pocket / Q000188:drug therapy* / Q000382:microbiology; D011100:Polyglycolic Acid / Q000737:chemistry; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D013203:Staphylococcal Infections / Q000188:drug therapy; D013211:Staphylococcus aureus / Q000187:drug effects; D013752:Tetracycline / Q000008:administration & dosage* / Q000494:pharmacology; D014961:X-Ray Diffraction; D003313:Zea mays / Q000737:chemistry; D015028:Zein / Q000737:chemistry*
chemical_list: D000900:Anti-Bacterial Agents; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; D015028:Zein; D013752:Tetracycline