title: Nanocapsule@xerogel microparticles containing sodium diclofenac: a new strategy to control the release of drugs.
abstract: The aim of this work was to evaluate the potentiality to control the drug release of a new architecture of microparticles organized at the nanoscopic scale by assembling polymeric nanocapsules at the surface of drug-loaded xerogels. Xerogel was prepared by sol-gel method using sodium diclofenac, as hydrophilic drug model, and coated by spray-drying. After coating, the surface areas decreased from 82 to 28 m(2)/g, the encapsulation efficiency was 71% and SEM analysis showed irregular microparticles coated by the nanocapsules. Formulation showed satisfactory gastro-resistance presenting drug release lower than 3% (60 min) in acid medium. In water, the pure drug dissolved 92% after 5 min, uncoated drug-loaded xerogel released 60% and nanocapsule coated drug-loaded xerogel 36%. After 60 min, uncoated drug-loaded xerogel released 82% and nanocapsule coated drug-loaded xerogel 62%. In conclusion, the new system was able to control the release of the hydrophilic drug model.
authors: Programa de Pós-Graduação em Química, Instituto de Química, Universidade Federal do Rio Grande do Sul, CP 15003, Porto Alegre, RS, Brazil.
authors: Letícia Sias
authors: LS
authors: da Fonseca
authors: Rodrigo Paulo
authors: RP
authors: Silveira
authors: Alberto Marçal
authors: AM
authors: Deboni
authors: Edilson Valmir
authors: EV
authors: Benvenutti
authors: Tânia M H
authors: TM
authors: Costa
authors: Sílvia S
authors: SS
authors: Guterres
authors: Adriana R
authors: AR
authors: Pohlmann
mesh_terms: D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage*; D002867:Chromones; D003692:Delayed-Action Preparations; D003890:Desiccation; D004008:Diclofenac / Q000008:administration & dosage*; D004339:Drug Compounding; D016503:Drug Delivery Systems; D008855:Microscopy, Electron, Scanning; D053758:Nanoparticles; D009584:Nitrogen; D011109:Polymethacrylic Acids; D013499:Surface Properties
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D002867:Chromones; D003692:Delayed-Action Preparations; D011109:Polymethacrylic Acids; D004008:Diclofenac; C038300:methylmethacrylate-methacrylic acid copolymer; C469689:tricetin; D009584:Nitrogen