Multivariate curve resolution of multidimensional excitation-emission quenching matrices of a Laurentian soil fulvic acid

• Type: Article in International Scientific Journal
• Date: 2006

Authors

Joaquim C G E Esteves da Silva (Author) FCUP; Maria J C G Tavares (Author) Other; Roma Tauler (Author) Other

Journal

Title: Chemosphere

Vol. 64 No. 3

Pages: 1939-1948

ISSN: 0045-6535

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 20 Citations

Scopus - 23 Citations

Scientific classification

FOS: Natural sciences > Earth and related Environmental sciences

Other information

Authenticus ID: P-004-HD7

DOI: 10.1016/j.chemosphere.2006.01.027

Abstract (EN): Fluorescence excitation-emission matrices (EEM) of aqueous solutions of Laurentian soil fulvic acid (LFA) at three concentrations (50, 75 and 100 mg/l) were obtained at two pH values (pH = 4.0 and 6.0) and as function of the Cu(II) ion concentration. The presence of Cu(II) ion provokes quenching of the intrinsic LFA fluorescence due to complex formation. Multivariate curve resolution (MCR-ALS) was used to successfully decompose single EEM into excitation and emission spectra for the detected components. Moreover, multidimensional (up to six dimensions) data matrices were generated by adding EEM collected as function of the LFA and Cu(II) concentrations and pH. MCR-ALS was able to resolve the excitation and emission spectra from these multidimensional data matrices given further information about the spectral variation profiles induced by the experimental factors. Conditional stability constants (logK(LFACu)) were calculated from the quenching profiles observed as function of the Cu(II) concentration, as well as, their trends as function of pH and LFA concentration were obtained - average (and standard deviation) of logK(LFACu) = 4.6 +/- 0.2. This EEM/MCR-ALS methodology constitutes a new tool for the study of natural organic matter under varying experimental conditions that characterize natural environmental systems.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 10