Mucosa-plate for direct evaluation of mucoadhesion of drug carriers.

The method to prepare mucosa-plates, glass slides covalently coated with mucin, is demonstrated. The use of the plate to evaluate mucoadhesion of nanocarriers made from different four polymeric materials, N-succinylchitosan (NS-chitosan), alginate (ALG), ethylcellulose (EC), and a blend of EC and methylcellulose (EC/MC), was demonstrated. While different mucoadhesion of the four carriers could be detected using mucosa-plate, the conventional viscosity measurement could not differentiate their mucin-binding ability. ALG and NS-chitosan nanospheres showed the best attachment to the mucosa-plate compared to the EC/MC and EC spheres. Capsaicin, a model hydrophobic drug, was loaded into the carriers and the ability of the different polymeric carriers to retain capsaicin at the stomach tissue was compared using an ex vivo fresh porcine stomach assay. Ability to retain capsaicin at the stomach tissue correlated well with binding affinity toward the mucosa-plate and the loading capacity of the carriers.