Spectroscopic techniques for quantitative characterization of Cu (II) and Hg (II) complexation by dissolved organic matter from lake sediment in arid and semi-arid region

Combination of two-dimensional correlation spectroscopy and parallel factor analysis to characterize the binding of heavy metals with DOM in lake sediments

“…In contrast, fluorescence excitation-emission matrix (EEM) quenching titration can be used to characterize the binding properties of fluorescent substances [5,16]. Although the overlapped peaks also occurred usually in the raw EEM plots [4,17], a multivariate modeling approach called parallel factor (PARAFAC) analysis can be used to deconvolute the overlapped peaks and obtain the exact changes of fluorescence intensities [5,16,18,19]. Recent studies have shown that fluorescence EEM quenching titration and PARAFAC analysis could be a useful tool to characterize the metal binding properties of DOM from surface waters [5], algal exudates [20], and leachates [21].…”

“…For many long-term contaminated lakes, Cu(II) and Zn(II) were part of main HMs in sediments due to the inflow of untreated or partially treated wastewater from industry, agriculture and sewage [3]. As a small but reactive fraction, dissolved organic matter (DOM) in lake sediments can interact with HMs to form organometal complex, and thus significantly affect the behaviors of HMs such as form, distribution, biotoxicity, migration and transformation [4,5]. The binding ability of DOM with HMs can greatly impact the water quality in aquatic environments, and also the mobilization and transportation of HMs toward the groundwater [4].…”

“…UV-vis absorption is a sensitive and effective tool to characterize the DOMs in sediments [4,11]. Through determining the changes in UV-vis spectra including absorbance and wavelengths in response to metal addition, it is possible to explore the HM-DOM complexes.…”

“…As a small but reactive fraction, dissolved organic matter (DOM) in lake sediments can interact with HMs to form organometal complex, and thus significantly affect the behaviors of HMs such as form, distribution, biotoxicity, migration and transformation [4,5]. The binding ability of DOM with HMs can greatly impact the water quality in aquatic environments, and also the mobilization and transportation of HMs toward the groundwater [4]. Therefore, investigations on the HM-DOM interaction were essential for understanding the biogechemical cycling of HMs in lake ecosystems.…”

Detection of Copper (II) and Cadmium (II) binding to dissolved organic matter from macrophyte decomposition by fluorescence excitation-emission matrix spectra combined with parallel factor analysis

“…Quenching of tryptophan-like fluorescence by Cu (II) and Ni (II) has been reported for settling sewage samples (Reynolds and Ahmad, 1995). The vast majority of such studies on metal binding have been performed on soil solutions, aquatic systems, and landfill leachate (Knoth de Zarruk et al, 2007;Wu et al, 2011;Guo et al, 2012).…”