ABSTRACT
A major challenge confronting pharmaceutical technologists today is the successful delivery of drugs, especially in view of therapeutically active peptides, proteins and other macromolecular agents such as oligonucleotides or gene vectors. Due to hostile environments, conformational and structural changes or proteolytic degradation can inactivate proteinaceous drugs before they reach the site of absorption. Additionally, the large spatial extension and hydrophilicity of biopharmaceuticals restrict their passage of biological barriers. Altogether, these complications result in poor bioavailability of biopharmaceuticals. One promising approach to improve the bioavailability of drugs is to use bioadhesive drug delivery systems (Lehr, 1994).
