Water-Soluble Ln(3+)-doped LaF(3) nanoparticles: retention of strong luminescence and potential as bio-labels.

J Fluoresc

Department of Chemistry, University of Victoria, P.O. Box 3065, Victoria, British Columbia, Canada V8W 3V6.

Published: July 2005

The use of optically robust, luminescent lanthanide-based particles is becoming an area of interest for bio-label-related chemistry, due to their long lifetimes and range of non-overlapping absorption and emission lines from the visible to the near-infrared. We report the synthesis and optical properties of water-soluble, luminescent Ln(3+)-doped nanoparticles (NPs) coordinated with a hydrophilic (RO)PO(3) (2-) ligand that facilitates the stabilization of the NPs in aqueous conditions, and that regulates particle growth to the nanometer range. The use of lanthanide ions as dopants, in particular Eu(3+) and Er(3+) ions, yields optically robust particles with narrow emission lines in the visible (591 nm) and in the near-infrared (1530 nm), respectively. Luminescent lifetimes range from the microsecond to the millisecond for Er(3+) and Eu(3+) ions, respectively, and the NPs are not expected to be susceptible to photo-bleaching due to the fact that the emissions arise from intra-4f transitions of the lanthanide ions.

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http://dx.doi.org/10.1007/s10895-005-2827-5DOI Listing

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