Surface, interfacial and molecular aspects of polymer bioadhesion on soft tissues

Interfacial phenomena related to the adhesive properties of synthetic polymers, hydrocolloids and related systems in contact with soft, natural tissues are discussed. The nature of the adhesive interface, the surface roughness, the chemical structure of the bioadhesive-candidate material, the swelling (hydration) at the adhesive interface, and the dynamic development of the bioadhesive bond strength are analyzed in terms of molecular and surface theories. Available in vitro testing techniques for bioadhesion provide an indication of the efficiency of proposed polymers as bioadhesives. These theoretical analyses and experimental results are used to establish general guidelines for the development of bioadhesive controlled release systems of bioactive agents for buccal, nasal, gastric, intestinal, urinary and rectal uses.