The behaviour of hyaluronan solutions in the presence of Hofmeister ions: A light scattering, viscometry and surface tension study

Lenka Musilová; Věra Kašpárková; Aleš Mráček; Antonín Minařík; Martin Minařík

doi:10.1016/j.carbpol.2019.02.032

The behaviour of hyaluronan solutions in the presence of Hofmeister ions: A light scattering, viscometry and surface tension study

Carbohydr Polym. 2019 May 15:212:395-402. doi: 10.1016/j.carbpol.2019.02.032. Epub 2019 Feb 19.

Authors

Lenka Musilová¹, Věra Kašpárková², Aleš Mráček³, Antonín Minařík¹, Martin Minařík⁴

Affiliations

¹ Tomas Bata University in Zlín, Faculty of Technology, Department of Physics and Material Engineering, nám. T.G. Masaryka 5555, 760 01 Zlín, Czech Republic; Centre of Polymer Systems, Tomas Bata University in Zlín, nám. T.G. Masaryka 5555, 760 01 Zlín, Czech Republic.
² Centre of Polymer Systems, Tomas Bata University in Zlín, nám. T.G. Masaryka 5555, 760 01 Zlín, Czech Republic; Tomas Bata University in Zlín, Faculty of Technology, Department of Fat, Surfactant and Cosmetics Technology, nám. T.G. Masaryka 5555, 760 01 Zlín, Czech Republic.
³ Tomas Bata University in Zlín, Faculty of Technology, Department of Physics and Material Engineering, nám. T.G. Masaryka 5555, 760 01 Zlín, Czech Republic; Centre of Polymer Systems, Tomas Bata University in Zlín, nám. T.G. Masaryka 5555, 760 01 Zlín, Czech Republic. Electronic address: mracek@ft.utb.cz.
⁴ Tomas Bata University in Zlín, Faculty of Technology, Department of Physics and Material Engineering, nám. T.G. Masaryka 5555, 760 01 Zlín, Czech Republic.

PMID: 30832872
DOI: 10.1016/j.carbpol.2019.02.032

Abstract

Dynamic light scattering (DLS), viscosity and surface tension (SFT) measurements were used to characterize influence of salts containing ions of Hofmeister series (Na₂SO₄, (NH₄)₂SO₄, NaSCN, NH₄SCN and NaCl) on the behaviour of hyaluronan in diluted solutions at a temperature range of 15-45 °C. The results of the study showed that chaotropic and kosmotropic ions notably influenced the folding and unfolding of hyaluronan coils due to interactions between a respective ion and hydrophilic or hydrophobic patches present in the backbone of the polymer chains. This was mainly proved by viscosity and light scattering measurements. The temperature dependence of the hydrodynamic diameter of the hyaluronan coil determined by DLS demonstrated that combinations of chaotropic and kosmotropic ions in one salt (NaCl, NaSCN and (HN₄)₂SO₄) can stabilize the size of the coil in a wide range of temperatures. Tensiometry measurements indicated that certain types of ions present in the solution caused an unfolding of the hyaluronan coils, leading to a decrease of SFT.

Keywords: Conformation; Hofmeister effect; Hyaluronan; Hydrodynamic diameter; Surface tension; Viscosity.