Structure of chitosan determines its interactions with mucin

Area of Science:

• Biomaterials Science
• Polymer Chemistry
• Drug Delivery

Background:

• Mucoadhesive biomaterials, like chitosan (CS), are crucial for transmucosal drug delivery.
• The precise molecular mechanisms of chitosan-mucin interactions and the influence of its structural properties remain unclear.

Purpose of the Study:

• To elucidate the molecular interactions between chitosan and mucin.
• To investigate the role of chitosan's degree of acetylation (DA) in these interactions.

Main Methods:

• Microviscosimetry
• Zeta potential analysis
• Isothermal titration calorimetry (ITC)
• Fluorescence quenching

Main Results:

• Chitosan interacts with porcine stomach mucin via a stoichiometric process.
• Electrostatic binding is the primary interaction force, supplemented by hydrogen bonds and hydrophobic associations.
• The degree of acetylation (DA) of chitosan significantly influences its conformation and the resulting complex formation.

Conclusions:

• Chitosan-mucin interactions are primarily driven by electrostatic forces, modulated by chitosan's DA.
• Understanding these interactions enables the rational design of chitosan-based nanostructured materials for transmucosal drug delivery.
• This research has implications for targeted therapies, such as for Helicobacter pylori infections.