ChemInform Abstract: Recent Progress on Silica Coating of Nanoparticles and Related Nanomaterials

Departamento de Química Física and Unidad Asociada CSIC Universidade de Vigo, Vigo 36310, Spain.
Advanced Materials (Impact Factor: 17.49). 03/2010; 22(11):1182-95. DOI: 10.1002/adma.200901263
Source: PubMed


In recent years, new strategies for silica coating of inorganic nanoparticles and organic nanomaterials, which differ from the classical methodologies, have emerged at the forefront of materials science. Silica as a coating material promises an unparalleled opportunity for enhancement of colloidal properties and functions by using core-shell rational designs and profiting from its synthetic versatility. This contribution provides a brief overview of recent progress in the synthesis of silica-coated nanomaterials and their significant impact in different areas such as spectroscopy, magnetism, catalysis, and biology.

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    • "Recently, epitaxial growth of an inorganic shell (mainly including CdS, ZnS, CdSe and SiO 2 ) on the surface of initial QD cores to prepare core/shell QDs has been explored for improving the quality of visible-emitting QDs in aqueous solution [16] [17] [18]. Among these core/shell structures, SiO 2 is one superior hydrophilic coating layer regarding their high stability , good biocompatibility and convenient processability in aqueous media [19] [20]. Nevertheless, the existence of a SiO 2 shell has its own limitation such as the decrease of fluorescence intensity [21] [22]. "
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    • "In the last decade, various methodologies for the silica coating of nanoparticles have been developed [21] [26]. Of these methods, reverse microemulsions, as thermodynamically stable, transparent , and isotropic liquid media with nanosized water pools, are particularly powerful [27] [28] [29]. "
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    • "Small molecule drugs, such as doxorubicin (Dox) and camptothecin, have been loaded onto mesoporous silica nanoparticles and studied for cancer treatment 4-7. Mesoporous silica has also been widely used as a coating material 8, 9. Nanoparticles made from a pyrolysis method, for instance, can be coated with a layer of silica and granted with good stability in aqueous solutions 3, 10-20. "
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