Controlled synthesis of uniform and monodisperse upconversion core/mesoporous silica shell nanocomposites for bimodal imaging

Chemistry. 2012 Feb 20;18(8):2335-41. doi: 10.1002/chem.201102599. Epub 2012 Jan 17.

Abstract

Here we report the design and controlled synthesis of monodisperse and precisely size-controllable UCNP@mSiO(2) nanocomposites smaller than 50 nm by directly coating a mesoporous silica shell (mSiO(2)) on upconversion nanocrystals NaYF(4):Tm/Yb/Gd (UCNPs), which can be used as near-infrared fluorescence and magnetic resonance imaging (MRI) agents and a platform for drug delivery as well. Some key steps such as transferring hydrophobic UCNPs to the water phase by using cetyltrimethylammonium bromide (CTAB), removal of the excess amount of CTAB, and temperature-controlled ultrasonication treatment should be adopted and carefully monitored to obtain uniform upconversion core/mesoporous silica shell nanocomposites. The excellent performance of the core-shell-structured nanocomposite in near-infrared fluorescence and magnetic resonance imaging was also demonstrated.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Diagnostic Imaging
  • Drug Delivery Systems
  • Magnetic Resonance Imaging
  • Nanocomposites / chemistry*
  • Nanoparticles / chemistry
  • Nanotechnology / methods*
  • Porosity
  • Silicon Dioxide / chemistry*
  • Spectroscopy, Near-Infrared

Substances

  • Silicon Dioxide