New light on a dark subject

Comment

Matthew P. Miller, Bailey E. Simone, Diane M. McKnight, Rose M. Cory, Mark W. Williams, Elizabeth Weeks Boyer

Research output: Contribution to journalArticle

43 Citations (Scopus)

Abstract

In their article, "New light on a dark subject: On the use of fluorescence data to deduce redox states of natural organic matter," Macalady and Walton-Day (2009) subjected natural organic matter (NOM) samples to oxidation, reduction, and photochemical transformation. Fluorescence spectra were obtained on samples, which were diluted "to bring maximum uvvisible absorbance values below 1.0." The spectra were fit to the Cory and McKnight (2005) parallel factor analysis (PARAFAC) model, and consistent variation in the redox state of quinone-like moieties was not detected. Based on these results they concluded that fitting fluorescence spectra to the Cory and McKnight (2005) PARAFAC model to obtain information about the redox state of quinone-like moieties in NOM is problematic. Recognizing that collection and correction of fluorescence spectra requires consideration of many factors, we investigated the potential for inner-filter effects to obscure the ability of fluorescence spectroscopy to quantify the redox state of quinone-like moieties. We collected fluorescence spectra on Pony Lake and Suwannee River fulvic acid standards that were diluted to cover a range of absorbance wavelengths, and fit these spectra to the Cory and McKnight (2005) PARAFAC model. Our results suggest that, in order for the commonly used inner-filter correction to effectively remove inner-filter effects, samples should be diluted such that the absorbance at 254 nm is less than 0.3 prior to the collection of fluorescence spectra. This finding indicates that inner-filter effects may have obscured changes in the redox signature of fluorescence spectra of the highly absorbing samples studied by Macalady and Walton-Day (2009).

Original languageEnglish (US)
Pages (from-to)269-275
Number of pages7
JournalAquatic Sciences
Volume72
Issue number3
DOIs
StatePublished - Jun 1 2010

Fingerprint

fluorescence
quinones
absorbance
factor analysis
filter
organic matter
fluorescence emission spectroscopy
sampling
fulvic acids
fluorescence spectroscopy
fulvic acid
wavelengths
oxidation
horses
lakes
rivers
wavelength
lake
river
effect

All Science Journal Classification (ASJC) codes

  • Ecology, Evolution, Behavior and Systematics
  • Aquatic Science
  • Ecology
  • Water Science and Technology

Cite this

Miller, M. P., Simone, B. E., McKnight, D. M., Cory, R. M., Williams, M. W., & Boyer, E. W. (2010). New light on a dark subject: Comment. Aquatic Sciences, 72(3), 269-275. https://doi.org/10.1007/s00027-010-0130-2
Miller, Matthew P. ; Simone, Bailey E. ; McKnight, Diane M. ; Cory, Rose M. ; Williams, Mark W. ; Boyer, Elizabeth Weeks. / New light on a dark subject : Comment. In: Aquatic Sciences. 2010 ; Vol. 72, No. 3. pp. 269-275.
@article{8144e377417a4e3892aff731492c8981,
title = "New light on a dark subject: Comment",
abstract = "In their article, {"}New light on a dark subject: On the use of fluorescence data to deduce redox states of natural organic matter,{"} Macalady and Walton-Day (2009) subjected natural organic matter (NOM) samples to oxidation, reduction, and photochemical transformation. Fluorescence spectra were obtained on samples, which were diluted {"}to bring maximum uvvisible absorbance values below 1.0.{"} The spectra were fit to the Cory and McKnight (2005) parallel factor analysis (PARAFAC) model, and consistent variation in the redox state of quinone-like moieties was not detected. Based on these results they concluded that fitting fluorescence spectra to the Cory and McKnight (2005) PARAFAC model to obtain information about the redox state of quinone-like moieties in NOM is problematic. Recognizing that collection and correction of fluorescence spectra requires consideration of many factors, we investigated the potential for inner-filter effects to obscure the ability of fluorescence spectroscopy to quantify the redox state of quinone-like moieties. We collected fluorescence spectra on Pony Lake and Suwannee River fulvic acid standards that were diluted to cover a range of absorbance wavelengths, and fit these spectra to the Cory and McKnight (2005) PARAFAC model. Our results suggest that, in order for the commonly used inner-filter correction to effectively remove inner-filter effects, samples should be diluted such that the absorbance at 254 nm is less than 0.3 prior to the collection of fluorescence spectra. This finding indicates that inner-filter effects may have obscured changes in the redox signature of fluorescence spectra of the highly absorbing samples studied by Macalady and Walton-Day (2009).",
author = "Miller, {Matthew P.} and Simone, {Bailey E.} and McKnight, {Diane M.} and Cory, {Rose M.} and Williams, {Mark W.} and Boyer, {Elizabeth Weeks}",
year = "2010",
month = "6",
day = "1",
doi = "10.1007/s00027-010-0130-2",
language = "English (US)",
volume = "72",
pages = "269--275",
journal = "Aquatic Sciences",
issn = "1015-1621",
publisher = "Birkhauser Verlag Basel",
number = "3",

}

Miller, MP, Simone, BE, McKnight, DM, Cory, RM, Williams, MW & Boyer, EW 2010, 'New light on a dark subject: Comment', Aquatic Sciences, vol. 72, no. 3, pp. 269-275. https://doi.org/10.1007/s00027-010-0130-2

New light on a dark subject : Comment. / Miller, Matthew P.; Simone, Bailey E.; McKnight, Diane M.; Cory, Rose M.; Williams, Mark W.; Boyer, Elizabeth Weeks.

In: Aquatic Sciences, Vol. 72, No. 3, 01.06.2010, p. 269-275.

Research output: Contribution to journalArticle

TY - JOUR

T1 - New light on a dark subject

T2 - Comment

AU - Miller, Matthew P.

AU - Simone, Bailey E.

AU - McKnight, Diane M.

AU - Cory, Rose M.

AU - Williams, Mark W.

AU - Boyer, Elizabeth Weeks

PY - 2010/6/1

Y1 - 2010/6/1

N2 - In their article, "New light on a dark subject: On the use of fluorescence data to deduce redox states of natural organic matter," Macalady and Walton-Day (2009) subjected natural organic matter (NOM) samples to oxidation, reduction, and photochemical transformation. Fluorescence spectra were obtained on samples, which were diluted "to bring maximum uvvisible absorbance values below 1.0." The spectra were fit to the Cory and McKnight (2005) parallel factor analysis (PARAFAC) model, and consistent variation in the redox state of quinone-like moieties was not detected. Based on these results they concluded that fitting fluorescence spectra to the Cory and McKnight (2005) PARAFAC model to obtain information about the redox state of quinone-like moieties in NOM is problematic. Recognizing that collection and correction of fluorescence spectra requires consideration of many factors, we investigated the potential for inner-filter effects to obscure the ability of fluorescence spectroscopy to quantify the redox state of quinone-like moieties. We collected fluorescence spectra on Pony Lake and Suwannee River fulvic acid standards that were diluted to cover a range of absorbance wavelengths, and fit these spectra to the Cory and McKnight (2005) PARAFAC model. Our results suggest that, in order for the commonly used inner-filter correction to effectively remove inner-filter effects, samples should be diluted such that the absorbance at 254 nm is less than 0.3 prior to the collection of fluorescence spectra. This finding indicates that inner-filter effects may have obscured changes in the redox signature of fluorescence spectra of the highly absorbing samples studied by Macalady and Walton-Day (2009).

AB - In their article, "New light on a dark subject: On the use of fluorescence data to deduce redox states of natural organic matter," Macalady and Walton-Day (2009) subjected natural organic matter (NOM) samples to oxidation, reduction, and photochemical transformation. Fluorescence spectra were obtained on samples, which were diluted "to bring maximum uvvisible absorbance values below 1.0." The spectra were fit to the Cory and McKnight (2005) parallel factor analysis (PARAFAC) model, and consistent variation in the redox state of quinone-like moieties was not detected. Based on these results they concluded that fitting fluorescence spectra to the Cory and McKnight (2005) PARAFAC model to obtain information about the redox state of quinone-like moieties in NOM is problematic. Recognizing that collection and correction of fluorescence spectra requires consideration of many factors, we investigated the potential for inner-filter effects to obscure the ability of fluorescence spectroscopy to quantify the redox state of quinone-like moieties. We collected fluorescence spectra on Pony Lake and Suwannee River fulvic acid standards that were diluted to cover a range of absorbance wavelengths, and fit these spectra to the Cory and McKnight (2005) PARAFAC model. Our results suggest that, in order for the commonly used inner-filter correction to effectively remove inner-filter effects, samples should be diluted such that the absorbance at 254 nm is less than 0.3 prior to the collection of fluorescence spectra. This finding indicates that inner-filter effects may have obscured changes in the redox signature of fluorescence spectra of the highly absorbing samples studied by Macalady and Walton-Day (2009).

UR - http://www.scopus.com/inward/record.url?scp=77952957068&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=77952957068&partnerID=8YFLogxK

U2 - 10.1007/s00027-010-0130-2

DO - 10.1007/s00027-010-0130-2

M3 - Article

VL - 72

SP - 269

EP - 275

JO - Aquatic Sciences

JF - Aquatic Sciences

SN - 1015-1621

IS - 3

ER -

Miller MP, Simone BE, McKnight DM, Cory RM, Williams MW, Boyer EW. New light on a dark subject: Comment. Aquatic Sciences. 2010 Jun 1;72(3):269-275. https://doi.org/10.1007/s00027-010-0130-2