Lanthanides to Quantum Dots Resonance Energy Transfer in Time-Resolved Fluoro-Immunoassays and Luminescence Microscopy
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- 作者：Loï ; c J. Charbonniè ; re ; Niko Hildebrandt ; Raymond F. Ziessel ; Hans-Gerd Lö ; hmannsrö ; ben
- 刊名：Journal of the American Chemical Society
- 出版年：2006
- 出版时间：October 4, 2006
- 年：2006
- 卷：128
- 期：39
- 页码：12800 - 12809
- 全文大小：883K
- 年卷期：v.128,no.39(October 4, 2006)
- ISSN：1520-5126
文摘
A time-resolved fluoro-immunoassay (TR-FIA) format is presented based on resonance energytransfer from visible emitting lanthanide complexes of europium and terbium, as energy donors, tosemiconductor CdSe/ZnS core/shell nanocrystals (quantum dots, QD), as energy acceptors. The spatialproximity of the donor-acceptor pairs is obtained through the biological recognition process of biotin, coatedat the surface of the dots (Biot-QD), and streptavidin labeled with the lanthanide markers (Ln-strep). Theenergy transfer phenomenon is evident from simultaneous lanthanide emission quenching and QD emissionsensitization with a 1000-fold increase of the QD luminescence decay time reaching the hundred 
s regime.Delayed emission detection allows for quantification of the recognition process and demonstrated a nearlyquantitative association of the biotins to streptavidin with sensitivity limits reaching 1.2 pM of QD. Spectralcharacterization permits calculation of the energy transfer parameters. Extremely large Förster radii (R0)values were obtained for Tb (104 Å) and Eu (96 Å) as a result of the relevant spectral overlap of donoremission and acceptor absorption. Special attention was paid to interactions with the varying constituentsof the buffer for sensitivity and transfer efficiency optimization. The energy transfer phenomenon was alsomonitored by time-resolved luminescence microscopy experiments. At elevated concentration (>10-5 M),Tb-strep precipitated in the form of pellets with long-lived green luminescence, whereas addition of Biot-QD led to red emitting pellets, with long excited-state decay times. The Ln-QD donor-acceptor hybridsappear as highly sensitive analytical tools both for TR-FIA and time-resolved luminescence microscopyexperiments.
s regime.Delayed emission detection allows for quantification of the recognition process and demonstrated a nearlyquantitative association of the biotins to streptavidin with sensitivity limits reaching 1.2 pM of QD. Spectralcharacterization permits calculation of the energy transfer parameters. Extremely large Förster radii (R0)values were obtained for Tb (104 Å) and Eu (96 Å) as a result of the relevant spectral overlap of donoremission and acceptor absorption. Special attention was paid to interactions with the varying constituentsof the buffer for sensitivity and transfer efficiency optimization. The energy transfer phenomenon was alsomonitored by time-resolved luminescence microscopy experiments. At elevated concentration (>10-5 M),Tb-strep precipitated in the form of pellets with long-lived green luminescence, whereas addition of Biot-QD led to red emitting pellets, with long excited-state decay times. The Ln-QD donor-acceptor hybridsappear as highly sensitive analytical tools both for TR-FIA and time-resolved luminescence microscopyexperiments.