The strategy for the development of oral biomolecules has always been a challenge for researchers due to their high molecular weight, chemical or enzymatic degradation and impermeability through the intestinal mucosa. Thiolate polymers – thiomers appear to be the most promising excipients for non-parenteral administration of very poorly absorbing drug hydrophilic macromolecules such as peptides, proteins and nucleic acids, which would improve the bioavailability of these therapeutic agents. Due to the immobilization of thiol groups on well-established multifunctional polymers such as polyacrylates and chitosans, their mucoadhesive, releasecontrolling, permeation enhancement and enzyme-inhibiting properties are significantly improved.
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