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Title: Determination of Technetium and its Speciation by Surface Enhanced Raman Spectroscopy

Abstract

Technetium-99 (Tc) is an important radionuclide of concern, and there is a great need for its detection and speciation analysis in the environment. For the first time, we report that surface-enhanced Raman spectroscopy (SERS) is capable of detecting an inorganic radioactive anion, pertechnetate (TcO4-), at ~10-7 M concentration levels. More importantly, the technique allows the detection of various species of Tc such as oxidized Tc(VII) and reduced or complexed Tc(IV) species using gold nanoparticles as a SERS substrate. The primary Raman scattering band of Tc(VII) occurs at about 904 cm-1, whereas reduced Tc(IV) and its humic and EDTA complexes show scattering bands at about 866 and 870 cm-1, respectively. Results also indicate that Tc(IV)-humic complexes are unstable and re-oxidize to TcO4- upon exposure to oxygen. This study demonstrates that SERS could potentially offer a new tool and opportunity in studying Tc and its speciation and interactions in the environment at low concentrations.

Authors:
 [1];  [1]
  1. ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Laboratory Directed Research and Development (LDRD) Program; USDOE Office of Science (SC)
OSTI Identifier:
930865
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Analytical Chemistry; Journal Volume: 79; Journal Issue: 4
Country of Publication:
United States
Language:
English
Subject:
38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY; DETECTION; PERTECHNETATES; RAMAN SPECTROSCOPY; TECHNETIUM 99; TECHNETIUM OXIDES; TECHNETIUM COMPLEXES; ENVIRONMENTAL MATERIALS; CHEMICAL ANALYSIS; Pertechnetate; SERS detection; Raman; Tc(VII); reduced Tc(IV)

Citation Formats

Gu, Baohua, and Ruan, Chuanmin. Determination of Technetium and its Speciation by Surface Enhanced Raman Spectroscopy. United States: N. p., 2007. Web. doi:10.1021/ac062052y.
Gu, Baohua, & Ruan, Chuanmin. Determination of Technetium and its Speciation by Surface Enhanced Raman Spectroscopy. United States. doi:10.1021/ac062052y.
Gu, Baohua, and Ruan, Chuanmin. Mon . "Determination of Technetium and its Speciation by Surface Enhanced Raman Spectroscopy". United States. doi:10.1021/ac062052y.
@article{osti_930865,
title = {Determination of Technetium and its Speciation by Surface Enhanced Raman Spectroscopy},
author = {Gu, Baohua and Ruan, Chuanmin},
abstractNote = {Technetium-99 (Tc) is an important radionuclide of concern, and there is a great need for its detection and speciation analysis in the environment. For the first time, we report that surface-enhanced Raman spectroscopy (SERS) is capable of detecting an inorganic radioactive anion, pertechnetate (TcO4-), at ~10-7 M concentration levels. More importantly, the technique allows the detection of various species of Tc such as oxidized Tc(VII) and reduced or complexed Tc(IV) species using gold nanoparticles as a SERS substrate. The primary Raman scattering band of Tc(VII) occurs at about 904 cm-1, whereas reduced Tc(IV) and its humic and EDTA complexes show scattering bands at about 866 and 870 cm-1, respectively. Results also indicate that Tc(IV)-humic complexes are unstable and re-oxidize to TcO4- upon exposure to oxygen. This study demonstrates that SERS could potentially offer a new tool and opportunity in studying Tc and its speciation and interactions in the environment at low concentrations.},
doi = {10.1021/ac062052y},
journal = {Analytical Chemistry},
number = 4,
volume = 79,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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