title: Evaluation of drug delivery characteristics of microspheres of PMMA-PCL-cholesterol obtained by supercritical-CO2 impregnation and by dissolution-evaporation techniques.
abstract: Poly(methyl methacrylate), PMMA, and of PMMA/Poly(epsilon-caprolactone), PCL, microspheres were loaded with different amounts of cholesterol by using a supercritical carbon dioxide (SC-CO2) impregnation process in order to use a clean technique with the absence of organic solvents, and to provide information for the infusion of additives into nonporous polymeric substrates. A conventional dissolution-evaporation method was also used to obtain PMMA and PMMA-PCL microparticles loaded with cholesterol. The obtained microspheres were characterized by environmental scanning electronic microscope, ESEM, nuclear magnetic resonance spectroscopy, NMR, and differential scanning calorimetry, DSC, thermal analysis. A comparison of drug release from particles obtained using both methods, the supercritical and the conventional, is presented.
authors.affiliation: Departamento de Química Macromolecular, Instituto de Ciencia y Tecnología de Polímeros, CSIC, c/Juan de la Cierva 3, 28006 Madrid, Spain. celvira@ictp.csic.es
authors.forename: Carlos
authors.initials: C
authors.lastname: Elvira
authors.forename: Alejandra
authors.initials: A
authors.lastname: Fanovich
authors.forename: Mar
authors.initials: M
authors.lastname: Fernández
authors.forename: Julio
authors.initials: J
authors.lastname: Fraile
authors.forename: Julio
authors.initials: J
authors.lastname: San Román
authors.forename: Concepción
authors.initials: C
authors.lastname: Domingo
mesh_terms: D002152:Calorimetry, Differential Scanning / Q000379:methods; D002245:Carbon Dioxide / Q000737:chemistry / Q000493:pharmacokinetics*; D002626:Chemistry, Pharmaceutical / Q000295:instrumentation / Q000379:methods; D002784:Cholesterol / Q000737:chemistry* / Q000493:pharmacokinetics; D016503:Drug Delivery Systems / Q000379:methods* / Q000639:trends; D005069:Evaluation Studies as Topic; D005079:Excipients / Q000737:chemistry / Q000493:pharmacokinetics; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008855:Microscopy, Electron, Scanning / Q000379:methods; D008863:Microspheres; D010316:Particle Size; D011091:Polyesters / Q000737:chemistry* / Q000493:pharmacokinetics; D019904:Polymethyl Methacrylate / Q000737:chemistry* / Q000493:pharmacokinetics; D012995:Solubility; D012996:Solutions / Q000737:chemistry / Q000493:pharmacokinetics; D013030:Spain; D013678:Technology, Pharmaceutical / Q000295:instrumentation / Q000379:methods; D013816:Thermodynamics; D014835:Volatilization
chemical_list: D005079:Excipients; D011091:Polyesters; D012996:Solutions; D002245:Carbon Dioxide; C016240:polycaprolactone; D019904:Polymethyl Methacrylate; D002784:Cholesterol