Honggang Fu

MCM-41 functionalized with YVO4:Eu3+: a novel drug delivery system

Luminescence functionalization of ordered mesoporous MCM-41 silica was realized by depositing a YVO4:Eu3+ phosphor layer on its surface via the Pechini sol-gel process. This material, which combines the mesoporous structure of MCM-41 and the strong red luminescence property of YVO4: Eu3+, has been studied as a host carrier for drug delivery/release systems. The structure, morphology, texture and optical properties of the materials were well characterized by x-ray diffraction ( XRD), Fourier infrared spectroscopy ( FT-IR), transmission electron microscopy ( TEM), N-2 adsorption and photoluminescence ( PL) spectra. The results indicated that the specific surface area and pore volume of MCM-41, which were directly correlated to the drug-loading amount and ibuprofen ( IBU) release rate, decreased in sequence after deposition of YVO4:Eu3+ and loading of IBU as expected. The IBU-loaded YVO4:Eu3+@ MCM-41 system still showed red luminescence under UV irradiation ( 365 nm) and a controlled release property for IBU. In addition, the emission intensity of Eu3+ increases with an increase in the cumulative released amount of IBU, making the extent of drug release easily identified, tracked and monitored by the change of luminescence, which demonstrates its potential application in drug delivery/release systems.

Hydrophilicity and formation mechanism of large-pore mesoporous TiO2 thin films with tunable pore diameters

Using n-butanol released in situ as the cosurfactant, transparent large-pore mesoporous nanocrystalline anatase (meso-nc-TiO2) thin films with narrow pore size distribution have been successfully synthesized in a Ti(OBun)4?P123?EtOH?HCl system. Furthermore, the mesopore size can be easily controlled in the range of 8.3?14.0?nm through adjusting the quantities of Ti(OBun)4, corresponding to the amount of n-butanol released in situ. X-ray diffraction, atomic force microscopy, scanning electron microscopy, transmission electron microscopy, and nitrogen sorption were used to investigate the relationship between the amount of Ti(OBun)4 and the structural parameters of the obtained meso-nc-TiO2 thin films. A reasonable mechanism is also proposed here to explain the formation of large-pore mesoporous TiO2 with tunable pore diameters. The hydrophilicity of our obtained films was evaluated by water contact angle measurement in air. It was found that, in the absence of ultraviolet (UV) illumination, the presented transparent large-pore meso-nc-TiO2 thin films exhibit high hydrophilicity.