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Indexed by:期刊论文

Date of Publication:2010-09-01

Journal:ACS NANO

Included Journals:SCIE、EI、Scopus

Volume:4

Issue:9

Page Number:5389-5397

ISSN No.:1936-0851

Key Words:terbium chelate; tetramethylrhodamine; core-shell nanoparticle; luminescence resonance energy transfer

Abstract:The development of core-shell nanoparticles has shown a wide range of new applications in the fields of chemistry, bioscience, and materials science because of their improved physical and chemical properties over their single-component counterparts. In the present work, we took the core-shell nanoarchitectures as an example to research the luminescence resonance energy transfer (LRET) process between a luminescent Tb(3+) chelate, N,N,N(1),N(1)-[4`-phenyl-2,2`:6`,2`-terpyridine-6,6`-diyl]bis(methylenenitrilo)tetrakis(acetate)-Tb(3+) (PTTA-Tb(3+)), and an organic dye, 5-carboxytetramethylrhodamine (CTMR). PTTA-Tb(3+) and CTMR were chosen as the donor-acceptor pair of LRET in our model construction because of their effective spectral overlapping. The core shell nanoparticles featuring a CTMR-SiO(2) core surrounded by a concentric PTTA-Tb(3+)-SiO(2) shell were prepared using a reverse microemulsion method. These nanoparticles are spherical, uniform in size, and highly photostable. The results of LRET experiments show that the sensitized emission lifetime of the acceptor in the nanoparticles is significantly prolonged (similar to 246 mu s), which is attributed to the long emission lifetime of the Tb(3+) chelate donor. According to the results of the steady-state and time-resolved luminescence spectroscopy, an energy transfer efficiency of similar to 80% and a large Forster distance between the donor and the acceptor in the core-shell nanoparticles are calculated, respectively. The new core-shell nanoparticles with a high LRET efficiency and long Forster distance enable them to be promising optical probes for a variety of possible applications such as molecular imaging and multiplex signaling.