Alkyl Passivation and Amphiphilic Polymer Coating of Silicon Nanocrystals for Diagnostic Imaging
- 3 September 2010
- Vol. 6 (18), 2026-2034
- https://doi.org/10.1002/smll.201000825
Abstract
A method to produce biocompatible polymer‐coated silicon nanocrystals for medical imaging is shown. Silica‐embedded Si nanocrystals are formed by HSQ thermolysis. The nanocrystals are then liberated from the oxide and terminated with Si–H bonds by HF etching, followed by alkyl monolayer passivation by thermal hydrosilylation. The Si nanocrystals have an average diameter of 2.1 nm ± 0.6 nm and photoluminesce with a peak emission wavelength of 650 nm, which lies within the transmission window of 650–900 nm that is useful for biological imaging. The hydrophobic Si nanocrystals are then coated with an amphiphilic polymer for dispersion in aqueous media with the pH ranging between 7 and 10 and an ionic strength between 30 mM and 2 M, while maintaining a bright and stable photoluminescence and a hydrodynamic radius of only 20 nm. Fluorescence imaging of polymer‐coated Si nanocrystals in biological tissue is demonstrated, showing the potential for in vivo imaging.This publication has 49 references indexed in Scilit:
- Multifunctional nanoparticles as biocompatible targeted probes for human cancer diagnosis and therapyJournal of Materials Chemistry, 2009
- Biodegradable luminescent porous silicon nanoparticles for in vivo applicationsNature Materials, 2009
- Near-infrared narrow-band imaging of gold/silica nanoshells in tumorsJournal of Biomedical Optics, 2009
- Biocompatible Luminescent Silicon Quantum Dots for Imaging of Cancer CellsACS Nano, 2008
- Kupffer cells are central in the removal of nanoparticles from the organismParticle and Fibre Toxicology, 2007
- Renal clearance of quantum dotsNature Biotechnology, 2007
- Si nanocrystals in SiO2 films analyzed by small angle X-ray scatteringThin Solid Films, 2007
- A new solution route to hydrogen-terminated silicon nanoparticles: synthesis, functionalization and water stabilityNanotechnology, 2007
- Process for Preparing Macroscopic Quantities of Brightly Photoluminescent Silicon Nanoparticles with Emission Spanning the Visible SpectrumLangmuir, 2003
- Assembly and Self-Organization of Silver Nanocrystal Superlattices: Ordered “Soft Spheres”The Journal of Physical Chemistry B, 1998