Fabrication of luminescent and mesoporous core-shell structured nanocomposites and their application as drug carrier

Monodisperse Y2O3:Eu3+ nanospheres were prepared by a facile urea-based homogeneous precipitation method. Core-shell structured bifunctional (mesporous, luminescent) nanocomposite was realized by coating mesoporous silica (MS) on the Y2O3:Eu3+ spheres via a simple sol-gel process. This nanocomposite was investigated as drug delivery/release carrier using ibuprofen (IBU) as model drug. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM). N-2 adsorption/desorption, Fourier transform infrared spectroscopy (FT-IR), and photoluminescence (PL) spectra were employed to characterize the as-prepared materials. The results indicated that the bifunctional nanocomposites with a uniform diameter of about 80 nm possess ordered mesoporous structure and strong red luminescence of Eu3+. Drug release test reveals that the Y2O3:Eu3+@SiO2 system has favorable drug release properties, especially modified by amino before drug loading. Additionally, the IBU-loaded Y2O3:Eu3+@SiO2 system still showed the red luminescence under UV irradiation. And the emission intensity of Eu3+ increases with an increase of the cumulative released amount of IBU, making the extent of drug release be easily identified, tracked and monitored by the change of luminescence during the release process and disease therapy. (C) 2009 Elsevier Inc. All rights reserved.