Thiomers, Mucoadhesion and Oral Delivery of Biomacromolecules

Dramatic advancement in the field of oral delivery of biomacromolecules occurred within the last decades. Recently, a novel class of multifunctional polymers has risen in the pharmaceutical literature. These thiolated polymers designated thiomers are based on a variety of well-known polymers such as alginate, poly(acrylic acid) or chitosan. They are synthesized via covalent attachment of sulfhydryl group bearing ligands to the polymeric backbone. Forming disulfide bonds with mucus substructures, these thiomers offer the advantage of more pronounced mucoadhesive features in comparison with their unmodified polymers. This review enhances a comprehensive insight on thiomers history, mucoadhesion process as a complex phenomenon and oral drug delivery of biomacromolecules.