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Title: Photophysics of (CdSe)ZnS Colloidal Quantum Dots in an Aqueous Environment Stabilized with Amino Acids and Genetically-Modified Proteins

Abstract

Using a combination of two amino acids, histidine and N-acetyl-cysteine, to replace the original organic capping groups of (CdSe)ZnS quantum dots, water-soluble and highly luminescent (CdSe)ZnS quantum dots have been successfully prepared at pH 8. Characterization by steady-state and time-resolved photoluminescence spectroscopy, and transient absorption spectroscopy, demonstrate that the electronic properties of these quantum dots exceed those of the original as-synthesized samples dissolved in a more-conventional organic solvent. Furthermore, these amino acid-stabilized quantum dots have been assembled onto a cellulose substrate via cellulose binding proteins that specifically bind to cellulose and was genetically engineered to harbor dual hexahistidine tags at the N- and C-termini to confer binding with the zinc(II) on the quantum dot surface. The spectroscopic measurements show that the protein-bound quantum dots continue to retain their desirable electronic properties when bound on the substrate. Meanwhile, the specific and very selective binding properties of the proteins have remained effective. (1)Select optimal greenhouse gas (GHG) and petroleum reduction strategies for each fleet location, (2)Meet or exceed Federal fleet GHG and petroleum reduction requirements outlined in the Guidance, (3)Acquire vehicles to support these strategies while minimizing fleet size and vehicle miles traveled (VMT), (4)Refine strategies based on agency performance.

Authors:
; ; ; ; ; ; ;
Publication Date:
Research Org.:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
982271
DOE Contract Number:
AC36-08GO28308
Resource Type:
Journal Article
Resource Relation:
Journal Name: Photochemical & Photobiological Sciences; Journal Volume: 6; Journal Issue: 2007
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; 59 BASIC BIOLOGICAL SCIENCES; 77 NANOSCIENCE AND NANOTECHNOLOGY; ABSORPTION SPECTROSCOPY; AMINO ACIDS; CELLULOSE; ENVIRONMENT; HARBORS; HISTIDINE; ORGANIC SOLVENTS; PHOTOLUMINESCENCE; PROTEINS; QUANTUM DOTS; SPECTROSCOPY; SUBSTRATES; TRANSIENTS; Basic Sciences

Citation Formats

Ai, X., Xu, Q., Jones, M., Song, Q., Ding, S.-Y., Ellingson, R. J., Himmel, M., and Rumbles, G.. Photophysics of (CdSe)ZnS Colloidal Quantum Dots in an Aqueous Environment Stabilized with Amino Acids and Genetically-Modified Proteins. United States: N. p., 2007. Web. doi:10.1039/b706471c.
Ai, X., Xu, Q., Jones, M., Song, Q., Ding, S.-Y., Ellingson, R. J., Himmel, M., & Rumbles, G.. Photophysics of (CdSe)ZnS Colloidal Quantum Dots in an Aqueous Environment Stabilized with Amino Acids and Genetically-Modified Proteins. United States. doi:10.1039/b706471c.
Ai, X., Xu, Q., Jones, M., Song, Q., Ding, S.-Y., Ellingson, R. J., Himmel, M., and Rumbles, G.. Mon . "Photophysics of (CdSe)ZnS Colloidal Quantum Dots in an Aqueous Environment Stabilized with Amino Acids and Genetically-Modified Proteins". United States. doi:10.1039/b706471c.
@article{osti_982271,
title = {Photophysics of (CdSe)ZnS Colloidal Quantum Dots in an Aqueous Environment Stabilized with Amino Acids and Genetically-Modified Proteins},
author = {Ai, X. and Xu, Q. and Jones, M. and Song, Q. and Ding, S.-Y. and Ellingson, R. J. and Himmel, M. and Rumbles, G.},
abstractNote = {Using a combination of two amino acids, histidine and N-acetyl-cysteine, to replace the original organic capping groups of (CdSe)ZnS quantum dots, water-soluble and highly luminescent (CdSe)ZnS quantum dots have been successfully prepared at pH 8. Characterization by steady-state and time-resolved photoluminescence spectroscopy, and transient absorption spectroscopy, demonstrate that the electronic properties of these quantum dots exceed those of the original as-synthesized samples dissolved in a more-conventional organic solvent. Furthermore, these amino acid-stabilized quantum dots have been assembled onto a cellulose substrate via cellulose binding proteins that specifically bind to cellulose and was genetically engineered to harbor dual hexahistidine tags at the N- and C-termini to confer binding with the zinc(II) on the quantum dot surface. The spectroscopic measurements show that the protein-bound quantum dots continue to retain their desirable electronic properties when bound on the substrate. Meanwhile, the specific and very selective binding properties of the proteins have remained effective. (1)Select optimal greenhouse gas (GHG) and petroleum reduction strategies for each fleet location, (2)Meet or exceed Federal fleet GHG and petroleum reduction requirements outlined in the Guidance, (3)Acquire vehicles to support these strategies while minimizing fleet size and vehicle miles traveled (VMT), (4)Refine strategies based on agency performance.},
doi = {10.1039/b706471c},
journal = {Photochemical & Photobiological Sciences},
number = 2007,
volume = 6,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
  • Abstract not provided.
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