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Title: Location deterministic biosensing from quantum-dot-nanowire assemblies

Abstract

Semiconductor quantum dots (QDs) with high fluorescent brightness, stability, and tunable sizes, have received considerable interest for imaging, sensing, and delivery of biomolecules. In this research, we demonstrate location deterministic biochemical detection from arrays of QD-nanowire hybrid assemblies. QDs with diameters less than 10 nm are manipulated and precisely positioned on the tips of the assembled Gold (Au) nanowires. The manipulation mechanisms are quantitatively understood as the synergetic effects of dielectrophoretic (DEP) and alternating current electroosmosis (ACEO) due to AC electric fields. The QD-nanowire hybrid sensors operate uniquely by concentrating bioanalytes to QDs on the tips of nanowires before detection, offering much enhanced efficiency and sensitivity, in addition to the position-predictable rationality. This research could result in advances in QD-based biomedical detection and inspires an innovative approach for fabricating various QD-based nanodevices.

Authors:
 [1];  [2];  [1];  [3]
  1. Materials Science and Engineering Program, Texas Materials Institute, University of Texas at Austin, Austin, Texas 78712 (United States)
  2. Department of Mechanical Engineering, University of Texas at Austin, Austin, Texas 78712 (United States)
  3. (United States)
Publication Date:
OSTI Identifier:
22310977
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 105; Journal Issue: 8; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
77 NANOSCIENCE AND NANOTECHNOLOGY; ALTERNATING CURRENT; BRIGHTNESS; EFFICIENCY; ELECTRIC FIELDS; FLUORESCENCE; GOLD; NANOSTRUCTURES; NANOWIRES; QUANTUM DOTS; QUANTUM WIRES; SEMICONDUCTOR MATERIALS; SENSITIVITY; SENSORS

Citation Formats

Liu, Chao, Kim, Kwanoh, Fan, D. L., E-mail: dfan@austin.utexas.edu, and Department of Mechanical Engineering, University of Texas at Austin, Austin, Texas 78712. Location deterministic biosensing from quantum-dot-nanowire assemblies. United States: N. p., 2014. Web. doi:10.1063/1.4893878.
Liu, Chao, Kim, Kwanoh, Fan, D. L., E-mail: dfan@austin.utexas.edu, & Department of Mechanical Engineering, University of Texas at Austin, Austin, Texas 78712. Location deterministic biosensing from quantum-dot-nanowire assemblies. United States. doi:10.1063/1.4893878.
Liu, Chao, Kim, Kwanoh, Fan, D. L., E-mail: dfan@austin.utexas.edu, and Department of Mechanical Engineering, University of Texas at Austin, Austin, Texas 78712. Mon . "Location deterministic biosensing from quantum-dot-nanowire assemblies". United States. doi:10.1063/1.4893878.
@article{osti_22310977,
title = {Location deterministic biosensing from quantum-dot-nanowire assemblies},
author = {Liu, Chao and Kim, Kwanoh and Fan, D. L., E-mail: dfan@austin.utexas.edu and Department of Mechanical Engineering, University of Texas at Austin, Austin, Texas 78712},
abstractNote = {Semiconductor quantum dots (QDs) with high fluorescent brightness, stability, and tunable sizes, have received considerable interest for imaging, sensing, and delivery of biomolecules. In this research, we demonstrate location deterministic biochemical detection from arrays of QD-nanowire hybrid assemblies. QDs with diameters less than 10 nm are manipulated and precisely positioned on the tips of the assembled Gold (Au) nanowires. The manipulation mechanisms are quantitatively understood as the synergetic effects of dielectrophoretic (DEP) and alternating current electroosmosis (ACEO) due to AC electric fields. The QD-nanowire hybrid sensors operate uniquely by concentrating bioanalytes to QDs on the tips of nanowires before detection, offering much enhanced efficiency and sensitivity, in addition to the position-predictable rationality. This research could result in advances in QD-based biomedical detection and inspires an innovative approach for fabricating various QD-based nanodevices.},
doi = {10.1063/1.4893878},
journal = {Applied Physics Letters},
number = 8,
volume = 105,
place = {United States},
year = {Mon Aug 25 00:00:00 EDT 2014},
month = {Mon Aug 25 00:00:00 EDT 2014}
}
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