title: Combination of adsorption by porous CaCO3 microparticles and encapsulation by polyelectrolyte multilayer films for sustained drug delivery.
abstract: Combination of adsorption by porous CaCO(3) microparticles and encapsulation by polyelectrolyte multilayers via the layer-by-layer (LbL) self-assembly was proposed for sustained drug release. Firstly, porous calcium carbonate microparticles with an average diameter of 5 microm were prepared for loading a model drug, ibuprofen (IBU). Adsorption of IBU into the pores was characterized by ultraviolet (UV), infrared (IR), thermogravimetric analysis (TGA), Brunauer-Emmett-Teller (BET) experiment and X-ray diffraction (XRD). The adsorbed IBU amount Gamma was 45.1mg/g for one-time adsorption and increased with increasing adsorption times. Finally, multilayer films of protamine sulfate (PRO) and sodium poly(styrene sulfonate) (PSS) were formed on the IBU-loaded CaCO(3) microparticles by the layer-by-layer self-assembly. Amorphous IBU loaded in the pores of the CaCO(3) microparticles had a rapider release in the gastric fluid and a slower release in the intestinal fluid, compared with the bare IBU crystals. Polyelectrolyte multilayers assembled on the drug-loaded particles by the LbL reduced the release rate in both fluids. In this work, polymer/inorganic hybrid core-shell microcapsules were fabricated for controlled release of poorly water-soluble drugs. The porous inorganic particles are useful to load drugs in amorphous state and the polyelectrolyte multilayer films coated on the particle assuage the initial burst release.
authors.affiliation: Research Institute of Materials Science, South China University of Technology, Guangzhou 510640, China.
authors.forename: Chaoyang
authors.initials: C
authors.lastname: Wang
authors.forename: Chengyi
authors.initials: C
authors.lastname: He
authors.forename: Zhen
authors.initials: Z
authors.lastname: Tong
authors.forename: Xinxing
authors.initials: X
authors.lastname: Liu
authors.forename: Biye
authors.initials: B
authors.lastname: Ren
authors.forename: Fang
authors.initials: F
authors.lastname: Zeng
mesh_terms: D000327:Adsorption; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000737:chemistry*; D001826:Body Fluids / Q000737:chemistry; D002119:Calcium Carbonate / Q000737:chemistry*; D003692:Delayed-Action Preparations; D004339:Drug Compounding / Q000379:methods*; D006863:Hydrogen-Ion Concentration; D007052:Ibuprofen / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D010316:Particle Size; D011108:Polymers / Q000737:chemistry*; D016062:Porosity; D012995:Solubility; D012997:Solvents; D013055:Spectrophotometry, Infrared; D013696:Temperature
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D003692:Delayed-Action Preparations; D011108:Polymers; D012997:Solvents; D002119:Calcium Carbonate; D007052:Ibuprofen