Chitosan-catechol: a polymer with long-lasting mucoadhesive properties

Area of Science:

• Biomaterials Science
• Polymer Chemistry
• Drug Delivery Systems

Background:

• Mucoadhesive polymers enhance drug residence time but often lack sufficient mucoadhesion.
• Existing modifications like thiolation and lectin functionalization present challenges such as disulfide bond reversibility and lectin toxicity.
• Improved mucoadhesive strategies are needed for effective mucosal drug delivery.

Purpose of the Study:

• To develop improved mucoadhesive polymers by chemically modifying existing ones.
• To investigate the potential of conjugating catechol moieties to chitosan for enhanced mucoadhesion.
• To evaluate the gastrointestinal (GI) tract retention of the modified polymer.

Main Methods:

• Conjugation of mussel-derived catechols to chitosan, a known mucoadhesive polymer.
• Assessment of the mucoadhesive properties and GI tract retention of the resulting chitosan-catechol conjugate.
• Analysis of the crosslinking mechanism between catechol and mucin.

Main Results:

• Chitosan-catechol demonstrated significantly improved GI tract retention compared to unmodified chitosan.
• The enhanced retention is attributed to irreversible catechol-mediated crosslinking with mucin.
• This modification strategy offers a promising approach for developing advanced mucoadhesive polymers.

Conclusions:

• Catechol modification of mucoadhesive polymers, specifically chitosan, enhances mucoadhesion through irreversible crosslinking.
• This approach represents a novel strategy for creating a new generation of mucoadhesive polymers for mucosal drug delivery.
• The findings suggest a potential for improved therapeutic efficacy through prolonged drug residence time at target sites.