Mucoadhesive Polymers in Medical Forms

Abstract

Mucoadhesive polymers are constitutive parts in formulations of mucoadhesive medical forms. These advanced formulations allow to extend the time of persistence of the drug on the mucosa of oral cavity, eyeball, nasal mucosa, respiratory tract, gastrointestinal tract or female genitals, to maintain high drug concentration on the application site and to ensure good bioavailability of the drug for the treatment of a local disease as well as for systemic drug absorption. Well established mucoadhesive polymers include hydrophilic polymers forming hydrogels, Carbomer, Polycarbophil, xanthan gum, sodium alginate, chitosan and cellulose derivatives. Thiolated polymers simulating the binding of glycoproteins to sialic and sulfonic acids to the mucosa show stronger mucoadhesive properties. Second-generation mucoadhesives, the substances with the ability to specifically link to epithelial cells through a receptor-ligand mediated mechanism, are lectins. They form a new fast type of adhesion without previous binding to mucous layer, called cytoadhesion. Mucoadhesive polymers, such as mucoadhesive proteins of mussels, are tested particularly in tissue engineering. Bacterial mucoadhesives are investigated as carriers for targeted drug delivery systems acting through the mucous membranes of the digestive tract.