title: Organosilicate-polymer drug delivery systems: controlled release and enhanced mechanical properties.
abstract: Dexamethasone-loaded poly(ethylene-co-vinyl acetate) (EVAc) nanocomposites were fabricated via solution-casting with three different organosilicates for study in a drug delivery system. X-ray diffraction (XRD) showed that all three nanocomposites were in an intercalated morphology. Release studies of dexamethasone into phosphate-buffered saline revealed that the presence of silicates reduced the rate of drug release, and this reduction was a function of volume fraction of silicate in the composite, as well as the aspect ratio of the silicate layers. It was also found that the presence of silicate in a nanocomposite resulted in an increase in the Young's modulus as compared to the pure polymer, and this increase was also a function of the volume fraction of silicate present as well as the aspect ratio of the silicate layers. Silicates are a viable additive to EVAc drug delivery systems, providing controlled release characteristics as well as enhanced mechanical properties in an economically and biologically safe manner.
authors.affiliation: School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY 14850, USA.
authors.forename: Stephen H
authors.initials: SH
authors.lastname: Cypes
authors.forename: W Mark
authors.initials: WM
authors.lastname: Saltzman
authors.forename: Emmanuel P
authors.initials: EP
authors.lastname: Giannelis
mesh_terms: D003692:Delayed-Action Preparations / Q000008:administration & dosage / Q000737:chemistry / Q000493:pharmacokinetics; D016503:Drug Delivery Systems / Q000379:methods*; D017646:Organosilicon Compounds / Q000008:administration & dosage* / Q000737:chemistry* / Q000493:pharmacokinetics; D011108:Polymers / Q000008:administration & dosage* / Q000737:chemistry* / Q000493:pharmacokinetics; D013314:Stress, Mechanical
chemical_list: D003692:Delayed-Action Preparations; D017646:Organosilicon Compounds; D011108:Polymers