title: Drug delivery formulations of ordered and nonordered mesoporous silica: comparison of three drug loading methods.
abstract: A poorly soluble model drug, indomethacin (IMC), was loaded into two types of silica particles using three different loading methods. The loading efficiency and the extent/rate of drug release were evaluated. Widely used equipment in pharmaceutical laboratories, rotavapor and fluid bed, were used in the loading. The porous materials used were ordered mesoporous silica MCM-41 and nonordered silica gel Syloid 244 FP EU. The materials differ both in their pore properties and particle sizes. Tablets were successfully compressed from the IMC-loaded particles. Mechanical stability of the porous structures was studied with XRPD and nitrogen sorption after tableting and drug release was evaluated at pH 5.5 before and after tableting. The release of the poorly soluble IMC was faster from the Syloid than from the MCM-41, presumably due to the larger pore size and smaller particle size. Loading of IMC into the MCM-41 microparticles improved the drug dissolution, and blending the microparticles with pharmaceutical excipients improved the IMC release even further. The fast release was also maintained after tableting. Loading of IMC into the Syloid particles alone was sufficient to produce similar IMC release profiles, as in the case of MCM-41 with the excipients.
authors.affiliation: Division of Pharmaceutical Technology, Faculty of Pharmacy, FIN-00014 University of Helsinki, Helsinki, Finland. Electronic address: tarja.limnell@orionpharma.com.
authors.forename: Tarja
authors.initials: T
authors.lastname: Limnell
authors.affiliation: Division of Pharmaceutical Technology, Faculty of Pharmacy, FIN-00014 University of Helsinki, Helsinki, Finland.
authors.forename: Hélder A
authors.initials: HA
authors.lastname: Santos
authors.affiliation: Laboratory of Industrial Physics, Department of Physics and Astronomy, FIN-20014 University of Turku, Turku, Finland.
authors.forename: Ermei
authors.initials: E
authors.lastname: Mäkilä
authors.affiliation: Laboratory of Industrial Physics, Department of Physics and Astronomy, FIN-20014 University of Turku, Turku, Finland.
authors.forename: Teemu
authors.initials: T
authors.lastname: Heikkilä
authors.affiliation: Laboratory of Industrial Physics, Department of Physics and Astronomy, FIN-20014 University of Turku, Turku, Finland.
authors.forename: Jarno
authors.initials: J
authors.lastname: Salonen
authors.affiliation: Laboratory of Industrial Chemistry, Process Chemistry Centre, FIN-20500 Åbo Akademi, Turku, Finland.
authors.forename: Dmitry Yu
authors.initials: DY
authors.lastname: Murzin
authors.affiliation: Laboratory of Industrial Chemistry, Process Chemistry Centre, FIN-20500 Åbo Akademi, Turku, Finland.
authors.forename: Narendra
authors.initials: N
authors.lastname: Kumar
authors.affiliation: Division of Pharmaceutical Technology, Faculty of Pharmacy, FIN-00014 University of Helsinki, Helsinki, Finland.
authors.forename: Timo
authors.initials: T
authors.lastname: Laaksonen
authors.affiliation: Division of Pharmaceutical Technology, Faculty of Pharmacy, FIN-00014 University of Helsinki, Helsinki, Finland.
authors.forename: Leena
authors.initials: L
authors.lastname: Peltonen
authors.affiliation: Division of Pharmaceutical Technology, Faculty of Pharmacy, FIN-00014 University of Helsinki, Helsinki, Finland.
authors.forename: Jouni
authors.initials: J
authors.lastname: Hirvonen
mesh_terms: D000284:Administration, Oral; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage / Q000737:chemistry; D002626:Chemistry, Pharmaceutical; D002851:Chromatography, High Pressure Liquid; D019245:Compressive Strength; D004337:Drug Carriers / Q000737:chemistry*; D004339:Drug Compounding; D004355:Drug Stability; D005782:Gels; D006863:Hydrogen-Ion Concentration; D007213:Indomethacin / Q000008:administration & dosage / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D010316:Particle Size; D016062:Porosity; D033362:Powder Diffraction; D012822:Silicon Dioxide / Q000737:chemistry*; D012995:Solubility; D013499:Surface Properties; D013607:Tablets; D013678:Technology, Pharmaceutical / Q000379:methods*; D014961:X-Ray Diffraction
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D004337:Drug Carriers; D005782:Gels; D013607:Tablets; D012822:Silicon Dioxide; D007213:Indomethacin