Publication detail

Molecular organization and conformational changesof humic acids in dependence on their concentrationin various aqueous solutions

KLUČÁKOVÁ, M. VĚŽNÍKOVÁ, K.

Original Title

Type

conference paper

Language

English

Original Abstract

Conformational changes of humic acids in different aqueous solutions were studied by means of two novelty methods: high resolution ultrasound spectrometry (HRUS) and micro-rheology (mR). Obtained results were compared with those of more conventional method of dynamic light scattering (DLS). The HRUS method is based on the measurement of parameters of ultrasonic waves propagating through the sample. The attenuation describes the decay of the amplitude of the ultrasonic wave with the distance travelled. The velocity is the speed of this wave and is related to the wavelength and the frequency of oscillation of the deformation. It is determined by the density and elasticity of the sample, which is strongly influenced by the molecular arrangement. The mR technics (in contrast to conventional rheology) relies on tracking the motions of the micro-sized tracer particles embedded in the sample. It can give information about a local inhomogeneity especially in the ultra-small scale materials. Our results showed that the organization of particles in diluted and concentrated solutions of humic acids is different. The conformational arrangement was strongly influence both the concentration and the character of surrounding medium. The decrease in compressibility indicated the formation of a more rigid structure, which could lead to the decrease in the binding ability of humic acids. Changes in sizes of particles detected using DLS resulted in their different mobility and obtained micro-rheological parameters. It was confirmed that both novelty methods employed were very sensitive and could be utilized as indicators of conformational changes in humic systems.

Keywords

Humic substances, molecular organization, conformation, ultrasound spectrometry, micro-rheology

Authors

KLUČÁKOVÁ, M.; VĚŽNÍKOVÁ, K.

RIV year

2015

Released

14. 10. 2015

Publisher

Tanger

Location

Ostrava

ISBN

978-80-87294-63-5

Book

NANOCON 2015 7th Internatonal Conference

Edition

Edition number

Pages from

645

Pages to

650

Pages count

BibTex

@inproceedings{BUT117937,
  author="Martina {Klučáková} and Kateřina {Věžníková}",
  title="Molecular organization and conformational changesof humic acids in dependence on their concentrationin various aqueous solutions",
  booktitle="NANOCON 2015 7th Internatonal Conference",
  year="2015",
  series="1",
  number="1",
  pages="645--650",
  publisher="Tanger",
  address="Ostrava",
  isbn="978-80-87294-63-5"
}