Long-wavelength emitting nanocrystals for bioassay applications

Valerie J. Leppert; Ashley S. Harvey; Geoff D. McCool; Forest T. Quinlan; Jun Feng; Guomin Shan; Pieter Stroeve; Subhash H. Risbud; Bruce D. Hammock; Ian M. Kennedy

doi:10.1117/12.451573

Translator Disclaimer

4 November 2002 Long-wavelength-emitting nanocrystals for bioassay applications

Valerie J. Leppert, Ashley S. Harvey, Geoff D. McCool, Forest T. Quinlan, Jun Feng, Guomin Shan, Pieter Stroeve, Subhash H. Risbud, Bruce D. Hammock, Ian M. Kennedy

Author Affiliations +

Proceedings Volume 4809, Nanoscale Optics and Applications; (2002) https://doi.org/10.1117/12.451573
Event: International Symposium on Optical Science and Technology, 2002, Seattle, WA, United States

Abstract

New fluorophores that can be excited using visible or near-infrared radiation are of considerable interest for application in environmental and complex bioassays, where background fluorescence is exacerbated by ultra-violet or blue excitation. Useful labels for biomolecules include infrared emitting semiconductor nanoparticles that can be blue-shifted into the near-infrared and visible through quantum confinement effects, oxides of iron, and rare earth oxides. In this work, the synthesis of 6 nm average diameter lead selenide nanocrystals (well below the Bohr exciton diameter of 92 nm) through a reverse micelle technique; and the synthesis of iron and europium oxides with particles less than 5 nm in diameter by pulsed laser ablation is reported. The europium oxide nanoparticles' emission showed a large Stokes shift (144 nm or 216 nm, depending on excitation wavelength); a narrow, symmetric emission line at 610 nm (FWHM of 8 nm); and long lifetime (300 μs). The Eu₂O₃ nanoparticles, which were coated with silica for functionalization, displayed a greatly enhanced sensitivity over a conventional ELISA (0.025 ng ml^-1 vs. 0.1 ng ml^-1) when run in an atrazine immunoassay.

Citation Download Citation

Valerie J. Leppert, Ashley S. Harvey, Geoff D. McCool, Forest T. Quinlan, Jun Feng, Guomin Shan, Pieter Stroeve, Subhash H. Risbud, Bruce D. Hammock, and Ian M. Kennedy "Long-wavelength-emitting nanocrystals for bioassay applications", Proc. SPIE 4809, Nanoscale Optics and Applications, (4 November 2002); https://doi.org/10.1117/12.451573

ACCESS THE FULL ARTICLE