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bioRxiv · 10.1101/2023.03.16.532902

Production of isotopically enriched high molecular weight hyaluronic acid and characterization by solid-state NMR

Rampratap, P.·Lasorsa, A.·Perrone, B.·van der Wel, P. C. A.·Walvoort, M.
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Abstract

Hyaluronic acid (HA) is a naturally occurring polysaccharide that is abundant in the extracellular matrix (ECM) of all vertebrate cells. HA-based hydrogels have attracted great interest for biomedical applications due to their high viscoelasticity and biocompatibility. In both ECM and hydrogel applications, high molecular weight (HMW)-HA can absorb a large amount of water to yield matrices with a high level of structural integrity. To understand the molecular underpinnings of structural and functional properties of HA-containing hydrogels, few techniques are available. Nuclear magnetic resonance (NMR) spectroscopy is a powerful tool for such studies, e.g. 13C NMR measurements can reveal the structural and dynamical features of (HMW) HA. However, a major obstacle to 13C NMR is the low natural abundance of 13C, necessitating the generation of HMW-HA that is enriched with 13C isotopes. Here we present a convenient method to obtain 13C- and 15N-enriched HMW-HA in good yield from Streptococcus equi subsp. zooepidemicus. The labeled HMW-HA has been characterized by solution and magic angle spinning (MAS) solid-state NMR spectroscopy, as well as other methods. These results will open new ways to study the structure and dynamics of HMW-HA-based hydrogels, and interactions of HMW-HA with proteins and other ECM components, using advanced NMR techniques.

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Rampratap, P., Lasorsa, A., Perrone, B., van der Wel, P. C. A., Walvoort, M.. 2023-03-20. Production of isotopically enriched high molecular weight hyaluronic acid and characterization by solid-state NMR. https://doi.org/10.1101/2023.03.16.532902

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