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Direct Observation of Intrachain Hydrogen Bonds in Aqueous Hyaluronan.

ABSTRACT: We use two-dimensional infrared spectroscopy to study the interactions between the amide and carboxylate anion groups of hyaluronan polymers at neutral pH. The spectra reveal the presence of intrachain hydrogen bonds between the amide and carboxylate anion groups in aqueous solution. We determine the relative orientation of the amide and carboxylate anion groups when forming this hydrogen bond and quantify the fraction of amide groups that participate in hydrogen bonding. We find that a variation of the pH and/or temperature has a negligible effect on this fraction, whereas the persistence length of the hyaluronan chains and the associated viscosity of hyaluronan solutions are known to change significantly. We conclude that the hydrogen bonding between the amide and carboxylate anion groups does not significantly contribute to the chain rigidity of hyaluronan polymers.

SUBMITTER: Giubertoni G

PROVIDER: S-EPMC6767362 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature

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Direct Observation of Intrachain Hydrogen Bonds in Aqueous Hyaluronan.

Giubertoni Giulia G Koenderink Gijsje H GH Bakker Huib J HJ

The journal of physical chemistry. A 20190912 38

We use two-dimensional infrared spectroscopy to study the interactions between the amide and carboxylate anion groups of hyaluronan polymers at neutral pH. The spectra reveal the presence of intrachain hydrogen bonds between the amide and carboxylate anion groups in aqueous solution. We determine the relative orientation of the amide and carboxylate anion groups when forming this hydrogen bond and quantify the fraction of amide groups that participate in hydrogen bonding. We find that a variatio ...[more]

PMID: 31478665

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