TY - JOUR
T1 - The use of high resolution graphite furnace molecular absorption spectrometry (HR -MAS) for total fluorine determination in extractable organofluorines (EOF)
AU - Akhdhar, Abdullah
AU - Schneider, Mauana
AU - Orme, Alice
AU - Schultes, Lara
AU - Raab, Andrea
AU - Krupp, Eva M.
AU - Benskin, Jonathan P.
AU - Welz, Bernhard
AU - Feldmann, Jörg
N1 - Acknowledgment
A.A. would like to thank the Ministry of Education and University of Jeddah in Saudi Arabia through the Cultural Bureau of Saudi Arabia, London for their financial support during the study period. A.O. wishes to thank the Royal Society of Chemistry Analytical Trust Fund for funding. M.S. would like to thank the Conselho Nacional de Desenvolvimento Científico e Tecnológico - CNPq for the financial support. L.S., J.B. and J.F. thank Formas for financial support (Grant number 2013–00794).
PY - 2020/3/1
Y1 - 2020/3/1
N2 - The determination of total fluorine content using high-resolution graphite furnace continuum source molecular absorption spectrometry (HR- MAS) has been employed in a variety of samples for over 10 years. However, most of the samples analysed by HR- MAS are rich in fluoride, with negligible levels of organic fluorinated species. With an increase in concern surrounding per- and polyfluoroalkyl substances (PFASs), new methods to measure total fluorine of organofluorine using different techniques have been developed. However, no studies focused on PFASs behaviour in HR-MAS have been performed. As these compounds encompass a wide range of different structures, boiling points, decomposition temperatures and matrix interactions, a loss of accuracy can occur when an aqueous external calibration is performed using only one compound. To overcome this issue, an investigation into permanent modifiers for the graphite furnace was performed. After optimisation similar sensitivity for different PFCA was achieved when 400 μg of W was used as a permanent modifier together with an optimised temperature program. The relative deviation between the different PFCA standard slopes relative to the PFOA slope was lower than 15%. The instrumental limit of detection and quantification (LOD and LOQ, respectively) of total fluorine as total PFCA was 0.1 mg L−1 and 0.3 mg L−1, respectively, while the method LOD and LOQ (using solid phase extraction) was 0.3 μg L−1 and 1.0 μg L−1, respectively. The developed method gave satisfactory recoveries for the spiked PFCA into seawater, river water and effluent using PFOA calibration standards. The optimised method is useful for measuring extractable organofluorines (EOF) when only ionic PFASs such as PFCA are expected. When other organofluorines are expected, the results using HR GF-MAS should be taken with caution.
AB - The determination of total fluorine content using high-resolution graphite furnace continuum source molecular absorption spectrometry (HR- MAS) has been employed in a variety of samples for over 10 years. However, most of the samples analysed by HR- MAS are rich in fluoride, with negligible levels of organic fluorinated species. With an increase in concern surrounding per- and polyfluoroalkyl substances (PFASs), new methods to measure total fluorine of organofluorine using different techniques have been developed. However, no studies focused on PFASs behaviour in HR-MAS have been performed. As these compounds encompass a wide range of different structures, boiling points, decomposition temperatures and matrix interactions, a loss of accuracy can occur when an aqueous external calibration is performed using only one compound. To overcome this issue, an investigation into permanent modifiers for the graphite furnace was performed. After optimisation similar sensitivity for different PFCA was achieved when 400 μg of W was used as a permanent modifier together with an optimised temperature program. The relative deviation between the different PFCA standard slopes relative to the PFOA slope was lower than 15%. The instrumental limit of detection and quantification (LOD and LOQ, respectively) of total fluorine as total PFCA was 0.1 mg L−1 and 0.3 mg L−1, respectively, while the method LOD and LOQ (using solid phase extraction) was 0.3 μg L−1 and 1.0 μg L−1, respectively. The developed method gave satisfactory recoveries for the spiked PFCA into seawater, river water and effluent using PFOA calibration standards. The optimised method is useful for measuring extractable organofluorines (EOF) when only ionic PFASs such as PFCA are expected. When other organofluorines are expected, the results using HR GF-MAS should be taken with caution.
KW - Per- and polyfluoroalkyl substances
KW - HR-MAS
KW - Fluorine determination
KW - POP
KW - PFAS
KW - LIQUID-CHROMATOGRAPHY
KW - PERFLUOROOCTANE SULFONATE
KW - WATER
UR - http://www.scopus.com/inward/record.url?scp=85075355840&partnerID=8YFLogxK
U2 - 10.1016/j.talanta.2019.120466
DO - 10.1016/j.talanta.2019.120466
M3 - Article
C2 - 31892068
VL - 209
JO - Talanta
JF - Talanta
SN - 0039-9140
M1 - 120466
ER -