Publication detail

Fluorescence analysis of Cu(II), Pb(II) and Hg(II) ion binding to humic and fulvic acids

ENEV, V. TÜRKEOVÁ, I. SZEWIECZKOVÁ, J. DOSKOČIL, L. KLUČÁKOVÁ, M.

Original Title

Fluorescence analysis of Cu(II), Pb(II) and Hg(II) ion binding to humic and fulvic acids

Czech Title

Studium vazby a komplexace iontů těžkých kovů Cu(II), Pb(II) a Hg(II) s huminovými a fulvinovými kyselinami pomocí fluorescenční spektrometrie

English Title

Fluorescence analysis of Cu(II), Pb(II) and Hg(II) ion binding to humic and fulvic acids

Type

abstract

Language

en

Original Abstract

Various methods and techniques have been used for studying humic substances binding to metal ions, among which steady-state fluorescence spectroscopy has proven to be one of the most promising and productive. The aim of this work was study molecular and quantitative analysis of metal ion binding to humic substances (HS). The object of our study was two standards of humic substances (Elliott Soil standard HA 1S102H and Elliott Soil standard FA 2S102F). All samples of IHSS standards HS were characterized by elemental analysis (EA), ultraviolet-visible spectroscopy (UV/Vis), Fourier transform infrared spectroscopy (FTIR) and steady-state fluorescence spectroscopy. UV/Vis spectra of aqueous solutions HS were measured by spectrophotometer Hitachi U-3900 in the wavelength range of 200–900 nm. Absorption coefficients (EET/EBz and E465/E665) of HS were calculated from the absorbance values. Infrared spectroscopy is a useful technique in characterization of structure, functional groups and formation modes of HS. For the fluorescence experiments the final concentration of the HS was adjusted to 10 and 15 mg∙L–1. All fluorescence spectra were performed on a Horiba Scientific Fluorolog. The fluorescence intensity (IF) values (in CPS) of samples were corrected using method of Lakowicz. A fluorescence titration method was used for determining metal ion complexing capacities and stability constants of metal ion complexes of standards HS. Titration with Cu(II), Pb(II) and Hg(II) ions decreased fluorescence intensities of HS. Chemical parameters on the complexation of Cu(II), Pb(II) and Hg(II) ions, including the conditional stability constants and the percentage of fluorophores participating in the complexation, were estimated by the modified Stern–Volmer equation.

Czech abstract

Předložená práce se zabývá studiem vazebných možností půdních HL s vybranými ionty těžkých kovů. Předmětem naši studie byly standardy půdních HL (Elliott Soil HK 1S102H a Elliott Soil FK 2S102F), které jsou dodávány společností International Humic Substances Society – IHSS. Všechny vzorky půdních HL byly charakterizovány pomocí elementární analýzy (EA) se zaměřením na obsah biogenních prvků (C, H, N, S, O), UV/Vis spektrometrie, infračervené spektrometrie s Fourierovou transformací a "steady-state" fluorescenční spektrometrie. Absorpční koeficienty (EET/EBz, a E465/E665) půdních HL byly vypočteny z příslušných hodnot absorbancí naměřených UV/Vis spekter. Infračervená spektrometrie byla využita k charakterizaci struktury a funkčních skupin, které se významně zapojují do vazby a imobilizace těžkých kovů těmito unikátními biokoloidními sloučeninami. Roztoky půdních HL byly připraveny o hmotnostní koncentraci 15 mg/dm3 v roztoku KNO3 při hodnotě pH ≈ 6. Všechny fluorescenční spektra byly měřeny na luminiscenčním spektrofotometru Horiba Scientific Fluorolog. Hodnoty fluorescenčních intenzit – IF (CPS) byly korigovány podle Lakowicze pro odstranění filtračních efektů prvního a druhého druhu roztoků huminových látek. Z naměřených experimentálních dat byly pomocí upravené Stern-Volmerovy rovnice získány parametry komplexace standardů HL s Cu(II), Pb(II) a Hg(II) ionty.

English abstract

Various methods and techniques have been used for studying humic substances binding to metal ions, among which steady-state fluorescence spectroscopy has proven to be one of the most promising and productive. The aim of this work was study molecular and quantitative analysis of metal ion binding to humic substances (HS). The object of our study was two standards of humic substances (Elliott Soil standard HA 1S102H and Elliott Soil standard FA 2S102F). All samples of IHSS standards HS were characterized by elemental analysis (EA), ultraviolet-visible spectroscopy (UV/Vis), Fourier transform infrared spectroscopy (FTIR) and steady-state fluorescence spectroscopy. UV/Vis spectra of aqueous solutions HS were measured by spectrophotometer Hitachi U-3900 in the wavelength range of 200–900 nm. Absorption coefficients (EET/EBz and E465/E665) of HS were calculated from the absorbance values. Infrared spectroscopy is a useful technique in characterization of structure, functional groups and formation modes of HS. For the fluorescence experiments the final concentration of the HS was adjusted to 10 and 15 mg∙L–1. All fluorescence spectra were performed on a Horiba Scientific Fluorolog. The fluorescence intensity (IF) values (in CPS) of samples were corrected using method of Lakowicz. A fluorescence titration method was used for determining metal ion complexing capacities and stability constants of metal ion complexes of standards HS. Titration with Cu(II), Pb(II) and Hg(II) ions decreased fluorescence intensities of HS. Chemical parameters on the complexation of Cu(II), Pb(II) and Hg(II) ions, including the conditional stability constants and the percentage of fluorophores participating in the complexation, were estimated by the modified Stern–Volmer equation.

Keywords

humic substances, titration, steady-state fluorescence spectroscopy, Stern-Volmer equation, fluorescence quenching

Released

02.09.2015

Publisher

Brno University of Technology, Faculty of Chemistry, Purkyňova 464/118, CZ-61200, Brno

Location

Brno, Czech Republic

ISBN

978-80-214-5228-2

Book

Chemistry & Life 2015, Brno University of Technology, Faculty of Chemistry, September 2–4, 2015, Book of Abstracts

Edition number

First

Pages from

61

Pages to

62

Pages count

2

BibTex


@misc{BUT116018,
  author="Vojtěch {Enev} and Irena {Solná} and Jana {Burdíková} and Leoš {Doskočil} and Martina {Klučáková}",
  title="Fluorescence analysis of Cu(II), Pb(II) and Hg(II) ion binding to humic and fulvic acids",
  annote="Various methods and techniques have been used for studying humic substances binding to metal ions, among which steady-state fluorescence spectroscopy has proven to be one of the most promising and productive.
The aim of this work was study molecular and quantitative analysis of metal ion binding to humic substances (HS). The object of our study was two standards of humic substances (Elliott Soil standard HA 1S102H and Elliott Soil standard FA 2S102F). All samples of IHSS standards HS were characterized by elemental analysis (EA), ultraviolet-visible spectroscopy (UV/Vis), Fourier transform infrared spectroscopy (FTIR) and steady-state fluorescence spectroscopy. UV/Vis spectra of aqueous solutions HS were measured by spectrophotometer Hitachi U-3900 in the wavelength range of 200–900 nm. Absorption coefficients (EET/EBz and E465/E665) of HS were calculated from the absorbance values. Infrared spectroscopy is a useful technique in characterization of structure, functional groups and formation modes of HS. For the fluorescence experiments the final concentration of the HS was adjusted to 10 and 15 mg∙L–1. All fluorescence spectra were performed on a Horiba Scientific Fluorolog. The fluorescence intensity (IF) values (in CPS) of samples were corrected using method of Lakowicz. A fluorescence titration method was used for determining metal ion complexing capacities and stability constants of metal ion complexes of standards HS. Titration with Cu(II), Pb(II) and Hg(II) ions decreased fluorescence intensities of HS. Chemical parameters on the complexation of Cu(II), Pb(II) and Hg(II) ions, including the conditional stability constants and the percentage of fluorophores participating in the complexation, were estimated by the modified Stern–Volmer equation.
",
  address="Brno University of Technology, Faculty of Chemistry, Purkyňova 464/118, CZ-61200, Brno",
  booktitle="Chemistry & Life 2015, Brno University of Technology, Faculty of Chemistry, September 2–4, 2015, Book of Abstracts",
  chapter="116018",
  howpublished="print",
  institution="Brno University of Technology, Faculty of Chemistry, Purkyňova 464/118, CZ-61200, Brno",
  year="2015",
  month="september",
  pages="61--62",
  publisher="Brno University of Technology, Faculty of Chemistry, Purkyňova 464/118, CZ-61200, Brno",
  type="abstract"
}