title: Control of drug release through the in situ assembly of stimuli-responsive ordered mesoporous silica with magnetic particles.
abstract: A site-selective controlled delivery system for controlled drug release is fabricated through the in situ assembly of stimuli-responsive ordered SBA-15 and magnetic particles. This approach is based on the formation of ordered mesoporous silica with magnetic particles formed from Fe(CO)5 via the surfactant-template sol-gel method and control of transport through polymerization of N-isopropyl acrylamide inside the pores. Hydrophobic Fe(CO)5 acts as a swelling agent as well as being the source of the magnetic particles. The obtained system demonstrates a high pore diameter (7.1 nm) and pore volume (0.41 cm(3) g(-1)), which improves drug storage for relatively large molecules. Controlled drug release through the porous network is demonstrated by measuring the uptake and release of ibuprofen (IBU). The delivery system displays a high IBU storage capacity of 71.5 wt %, which is almost twice as large as the highest value based on SBA-15 ever reported. In vitro testing of IBU loading and release exhibits a pronounced transition at around 32 degrees C, indicating a typical thermosensitive controlled release.
authors.affiliation: State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, 1954 Huashan Road, Shanghai 200030, PR China. smzhu@sjtu.edu.cn
authors.forename: Shenmin
authors.initials: S
authors.lastname: Zhu
authors.forename: Zhengyang
authors.initials: Z
authors.lastname: Zhou
authors.forename: Di
authors.initials: D
authors.lastname: Zhang
mesh_terms: D003198:Computer Simulation; D004058:Diffusion; D004337:Drug Carriers / Q000737:chemistry*; D006358:Hot Temperature; D008280:Magnetics; D015394:Molecular Structure; D004364:Pharmaceutical Preparations / Q000737:chemistry*; D016062:Porosity; D012822:Silicon Dioxide / Q000737:chemistry*; D013997:Time Factors; D014783:Viscosity; D014835:Volatilization
chemical_list: D004337:Drug Carriers; D004364:Pharmaceutical Preparations; D012822:Silicon Dioxide