Permeability of pig urinary bladder wall: the effect of chitosan and the role of calcium.

Chitosan is a cationic polysaccharide widely employed as an absorption enhancer. The aim of this work was to examine the effect of chitosan on the permeability of isolated pig urinary bladder wall as well as to determine the role of calcium ions in this process. Besides permeability studies, scanning electron microscopy and fluorescent microscopy were applied to get an insight into the mechanism by which chitosan increases the permeability of urinary bladder wall.

The correlation between zeta potential and mucoadhesion strength on pig vesical mucosa.

The detachment forces of various polymers are frequently measured to determine their mucoadhesion strength. As the process of mucoadhesion is a consequence of interactions between the mucus layer on mucosa and mucoadhesive polymers, it is greatly dependent on mucus and polymer structure including their charge. It is also known that the glycosaminoglycan layer, which covers the urinary bladder mucosa surface, is highly negatively charged.