A New Hyaluronan Modified with β-Cyclodextrin on Hydroxymethyl Groups Forms a Dynamic Supramolecular Network

Area of Science:

• Polymer Chemistry
• Supramolecular Chemistry
• Biomaterials Science

Background:

• Hyaluronan is a naturally occurring polysaccharide with significant biological importance.
• Modifying hyaluronan can impart new functionalities for advanced applications.
• Cyclodextrins are known for their ability to form host-guest complexes.

Purpose of the Study:

• To synthesize a novel hyaluronan derivative functionalized with beta-cyclodextrin units (CD-HA).
• To investigate the supramolecular assembly capabilities of CD-HA with multitopic guests.
• To evaluate the potential of CD-HA in constructing chemical stimuli-responsive materials.

Main Methods:

• Preparation of CD-HA via click chemistry between propargylated hyaluronan and monoazido-cyclodextrin.
• Characterization using 1H-nuclear magnetic resonance (NMR) spectroscopy and size exclusion chromatography.
• Assessment of host-guest complexation using isothermal titration calorimetry.

Main Results:

• A CD-HA derivative with a 4% degree of substitution was successfully synthesized.
• CD-HA formed virtual 1:1, 1:2, and 1:3 complexes with adamantane-based guests of varying sites.
• CD-HA chains formed supramolecular cross-linked networks with multitopic guests.
• The cross-linked network was reversible upon addition of a competing macrocycle.

Conclusions:

• The synthesized CD-HA polymer exhibits controllable supramolecular network formation.
• The reversibility of the network highlights its potential for stimuli-responsive applications.
• CD-HA is a promising component for designing advanced chemical stimuli-responsive supramolecular architectures.