Characteristic features of the major components of freshwater colloidal organic matter revealed by transmission electron and atomic force microscopy

Wilkinson, Kevin J.; Balnois, Eric; Leppard, Gary G.; Buffle, Jacques

doi:10.1016/s0927-7757(98)00874-7

Cited by 183 publications

(153 citation statements)

References 45 publications

Supporting

Mentioning

143

Contrasting

Order By: Relevance

“…Many complementary investigative techniques have been deployed including sedimentation (17), rheology (18b, 19a), electrokinetics (18b, 19a), imaging (16,25,26,27,28), and various forms of light scattering (20), particularly photon correlation spectroscopy (13,15,29). One unintentional consequence of the use of optical techniques (and indeed sedimentation and some atomic force microscopy) is that the length scales (ie, particle sizes) probed are typically hundreds to thousands of nm.…”

mentioning

confidence: 99%

Exploring How Organic Matter Controls Structural Transformations in Natural Aquatic Nanocolloidal Dispersions

King

Jarvie

2012

Environ. Sci. Technol.

View full text Add to dashboard Cite

show abstract

mentioning

confidence: 99%

Exploring How Organic Matter Controls Structural Transformations in Natural Aquatic Nanocolloidal Dispersions

King

Jarvie

2012

Environ. Sci. Technol.

View full text Add to dashboard Cite

show abstract

“…Maurice et al [29,30] , for example, have imaged aggregate structures of humic substances in aqueous solutions, and reported small spheres (10-50 nm) and "sponge-like ring structures". Wilkinson et al [31,32] performed both transmission electron and atomic force microscopy imaging on the freshwater colloidal organic matters and investigated the effects of solution pH and ionic strength on the size and conformation of two different HS on mica. Plaschke et al [33][34][35] performed in situ Fluid-AFM imaging on the sorbed humic acid colloids and investigated the influence of different pH conditions and Eu(III) ions on the agglomeration of humic acid.…”

mentioning

confidence: 99%

“…Recently, Gerin and Dufrêne [28] developed a procedure for probing the native surface structure of natural soil particles and characterized the properties of the adsorbed organic matter by combining AFM imaging and X-ray photoelectron spectrometry (XPS) analysis. A few reports have also described the use of AFM to characterize the structure of humic substances on mica after isolation from water streams and soils [29][30][31][32][33][34][35][36] . Maurice et al [29,30] , for example, have imaged aggregate structures of humic substances in aqueous solutions, and reported small spheres (10-50 nm) and "sponge-like ring structures".…”

mentioning

confidence: 99%

AFM study on the adsorption and aggregation behavior of dissolved humic substances on mica

Zhou

Lü

et al. 2006

SCI CHINA SER B

View full text Add to dashboard Cite

Humic substances constitute the major organic fractions of soils, sediments and natural waters, and play a dominant role in the binding, mobilization, transport and ultimate fate of organic contaminants in subsurface systems. In this paper, two humic acid samples, Guanting and Tianjin, with different origin and chemical compositions have been investigated with AFM imaging for their adsorption and aggregation behaviors on mica. While the Tianjin humic sample is found to form small spheres with 250 to 330 nm in diameter at lower concentrations, irregular loop-chain assemblies of hundreds of nanometer in diameter with the chain width of about 40 nm are dominant for the Guanting humic sample, which may attribute to the more polar aliphatic fractions in the chemical composition in the latter. The heterogeneous and polydisperse nature of humic substances with multiple structural features, such as sponge-like structures, perforated sheets, aggregate of spheres, branches and chain-like assemblies etc., is apparent at higher concentrations for both humic samples, showing morphologically new evidence for the dominant view of the humic dual-mode sorption model. With naphthalene introduced, the assemblies of Guanting humic substances clearly become more compact with significantly narrowed branches and less porous the perforated sheet-like structures. It is indicative of that smaller nanometer scale rings present along the perforated assemblies could potentially represent hydrophobic domains, which may facilitate the adsorption and aggregation of naphthalene onto the natural particle surfaces and therefore lead to an important role of dissolved humic substances in the sorption of environmental pollutants.Keywords: atomic force microscopy (AFM), dissolved humic substances, morphology, aggregation, adsorption.Humic substances (HS) are a category of naturally occurring, biogenic, heterogeneous organic materials found in or extracted from soils, sediments, and natural waters that can generally be characterized as being yellow-to-black in color, of highly variable relative molecular masses, and refractory [1,2] . Derived from a variety of organic precursors (plant biopolymers such as lignin etc.), plant residues and animal debris via both transformation and synthesis processes [3] under the profound geochemical alteration, including the microbiological and chemical degradation, sedimentation and diagenesis as well, humic substances com-AFM study on the adsorption and aggregation behavior of dissolved HS on mica 257 prise highly complex composites of partially or completely degraded biomolecules, carbohydrates, lipids, and proteins etc. However, they cannot be classified into any of the normal, easily defined categories of discrete materials such as proteins, polysaccharides, and polynucleotides. As the major organic constituents of soils, sediments and waters, humic substances are ubiquitous in all terrestrial and aquatic environments. They can form molecular aggregates, dispersed in different colloidal states in solutio...

show abstract

“…Fig. 4 ; (Santschi et al 1998;Wilkinson et al 1999)) show that their total length may be larger than 1 µm, whereas their thickness is often only a few nm. Furthermore, because they are often charged molecules (i.e.…”

Section: Autochthonous Macromolecules: Proteins Lipids and Polysacchmentioning

confidence: 99%

Contrasting Roles Of Natural Organic Matter On Colloidal Stabilization And Flocculation In Freshwaters

Reinhardt¹

2004

Flocculation in Natural and Engineered Environmental Systems

View full text Add to dashboard Cite

Characteristic features of the major components of freshwater colloidal organic matter revealed by transmission electron and atomic force microscopy

Cited by 183 publications

References 45 publications

Exploring How Organic Matter Controls Structural Transformations in Natural Aquatic Nanocolloidal Dispersions

Exploring How Organic Matter Controls Structural Transformations in Natural Aquatic Nanocolloidal Dispersions

AFM study on the adsorption and aggregation behavior of dissolved humic substances on mica

Contrasting Roles Of Natural Organic Matter On Colloidal Stabilization And Flocculation In Freshwaters

Contact Info

Product

Resources

About