Bioadhesive Polymers for Drug Delivery

Bioadhesion is commonly defined as the adhesion between two materials, at least one of which is biological in nature. Over the past few decades, bioadhesion-enhanced drug delivery has received a great deal of attention. Bioadhesive dosage forms may be designed to enable prolonged retention at the site of application, providing a controlled rate of drug release for improved therapeutic outcome. Application of dosage forms to mucosal surfaces may be of benefit to drug molecules not amenable to the oral route, such as those that undergo acid degradation or extensive first pass metabolism. The bioadhesive ability of a dosage form is dependent upon a variety of factors, including the nature of the mucosal tissue, and the physicochemical properties of the polymeric formulation. This chapter aims to provide an overview of the various aspects various aspects of bioadhesion, bioadhesive materials and their synthesis, factors affecting bioadhesion, evaluation methods, and finally, various bioadhesive drug delivery systems (buccal, nasal, ocular, gastro, vaginal, and rectal).