Molecular Origin of the Elastic State of Aqueous Hyaluronic Acid

Research output: Contribution to journalArticlepeer-review


  • Giulia Giubertoni
  • Federica Burla
  • Cristina Martinez-Torres
  • Biplab Dutta
  • Galja Pletikapic
  • Yves L.A. Rezus
  • Gijsje H. Koenderink
  • Huib J. Bakker

Colleges, School and Institutes

External organisations

  • FOM Institute for Atomic and Molecular Physics (AMOLF)
  • Unilever Research and Development


The macroscopic mechanical properties of biological hydrogels are broadly studied and successfully mimicked in synthetic materials, but little is known about the molecular interactions that mediate these properties. Here, we use two-dimensional infrared spectroscopy to study the pH-induced gelation of hyaluronic acid, a ubiquitous biopolymer, which undergoes a transition from a viscous to an elastic state in a narrow pH range around 2.5. We find that the gelation originates from the enhanced formation of strong interchain connections, consisting of a double amide-COOH hydrogen bond and an N-D-COO- hydrogen bond on the adjacent sugars of the hyaluronan disaccharide unit. We confirm the enhanced interchain connectivity in the elastic state by atomic force microscopy imaging.

Bibliographic note

Publisher Copyright: © 2019 American Chemical Society.


Original languageEnglish
Pages (from-to)3043-3049
Number of pages7
JournalJournal of Physical Chemistry B
Issue number14
Publication statusPublished - 11 Apr 2019