Mucoadhesive Drug Delivery Systems in Pharmaceutical Applications

Mucoadhesive drug delivery systems (MDDS) exploit the natural adhesive properties of polymers to attach therapeutic formulations to mucosal surfaces, including the oral, nasal, ocular, vaginal, rectal and gastrointestinal epithelia. By forming intimate contact with mucin‐rich layers, these systems prolong residence time at the site of action or absorption, enabling sustained or controlled release and reducing dosing frequency. Central to MDDS design are polymers capable of interpenetrating the mucus network and forming non‐covalent bonds—electrostatic, hydrogen‐bonding and hydrophobic interactions—with glycoprotein constituents. Commonly employed materials include chitosan and its derivatives, thiolated polysaccharides, carbomers and alginates, each offering distinct mucoadhesive strength, swelling behaviour and pH sensitivity. Advances in formulation engineering have yielded nano‐ and microparticulate carriers, in situ gelling systems and stimuli‐responsive hydrogels that further enhance drug stability, bioavailability and patient compliance. Key challenges remain in overcoming mucus turnover, variability in mucin composition, enzymatic degradation and ensuring reproducible performance across diverse physiological conditions. Emerging trends focus on biomimetic strategies that replicate the hierarchical structure of native mucus, integration of self-healing hydrogel networks and optimisation of polymer–drug interactions to achieve precision delivery and minimal systemic exposure.

Research from Nature Portfolio

Recent studies have elucidated the hierarchical assembly of intestinal mucin into viscoelastic gels that closely mimic the biophysical properties of native mucus. It has been shown that non-mucin proteins and calcium-mediated cross-links act in concert with disulfide bridges to form microscale domains which aggregate into a heterogeneous yield-stress fluid. Proteomic analysis has identified candidate proteins that drive this assembly, and rheological measurements confirm that the resulting gel exhibits mechanical and flow characteristics nearly identical to those of unaltered intestinal mucus. Insights from this work inform the rational design of mucoadhesive carriers that can emulate the selective barrier function and protective role of the mucosal lining.

Mucoadhesive Drug Delivery Systems in Pharmaceutical Applications publication trend

The graph below shows the total number of articles in mucoadhesive drug delivery systems in pharmaceutical applications across all publications each year (not limited to Nature Index journals).

Technical terms

Mucoadhesion: The process by which a material binds to mucosal membranes via non-covalent interactions.

Mucin: High-molecular-weight glycoproteins that form the gel network of mucus on epithelial surfaces.

Thiolated chitosan: Chitosan chemically modified to introduce sulfhydryl groups, enhancing mucoadhesion and cross-linking capacity.

Viscoelasticity: The property of a material to exhibit both viscous flow and elastic deformation under stress.

Transmucosal delivery: Drug administration through mucosal tissues to achieve local or systemic therapeutic effects.

References

1. Mucus‐Inspired Self‐Healing Hydrogels: A Protective Barrier for Cells against Viral Infection. Advanced Materials (2024).
2. Chitosan and Its Derivatives for Application in Mucoadhesive Drug Delivery Systems. Polymers (2018).
3. Interaction Between Chitosan and Mucin: Fundamentals and Applications. Biomimetics (2019).
4. Mucin gel assembly is controlled by a collective action of non-mucin proteins, disulfide bridges, Ca2+-mediated links, and hydrogen bonding. Scientific Reports (2018).