Interactions between Cationic Ion Pair Amphiphile Vesicles and Hyaluronan-A Physicochemical Study

Area of Science:

• Materials Science
• Biochemistry
• Physical Chemistry

Background:

• Catanionic ion pair amphiphiles form vesicles with potential applications in drug delivery.
• Hyaluronan is a biocompatible polysaccharide with significant biological roles.
• Understanding the interaction between hyaluronan and vesicles is crucial for developing advanced materials.

Purpose of the Study:

• To characterize the interactions between hyaluronan and catanionic ion pair amphiphile vesicles.
• To investigate the effect of charge ratio and hyaluronan molecular weight on vesicle structure.
• To determine the thermodynamic driving forces of these interactions.

Main Methods:

• High-resolution ultrasound spectroscopy (HR-US) for structural analysis.
• Size and ζ-potential titrations to monitor vesicle size and surface charge.
• Isothermal titration calorimetry (ITC) to quantify binding thermodynamics.
• Visual observations for qualitative assessment of vesicle morphology.

Main Results:

• A strong correlation was observed between HR-US, size titration, and visual observation.
• Hyaluronan-coated vesicles formed at lower charge ratios.
• Vesicle disintegration into larger structures (~2000 nm) occurred at higher charge ratios.
• Interaction intensity and disaggregation were dependent on hyaluronan molecular weight.
• ITC revealed strong exothermic interactions, confirming binding from the initial addition.

Conclusions:

• Hyaluronan effectively interacts with catanionic vesicles, influencing their structural integrity.
• The molecular weight of hyaluronan plays a critical role in the outcome of these interactions.
• The observed exothermic nature suggests favorable binding thermodynamics between hyaluronan and the vesicle system.