An in-vitro investigation of mucosa-adhesive materials for use in controlled drug delivery.

An in-vitro test system was developed to investigate the adhesiveness of various materials to mucus. The results obtained showed good agreement with the findings of previous in-vivo evaluations of mucosa-adhesives. Further investigations found that these materials become adhesive on hydration. Chain length, and the presence of ionizable groups in the molecule, were found to be determinate factors. The physical nature of the gel, and the location at which the mucoadhesive materials hydrated, were of less importance.