Strategies to Overcome the Enzymatic Barrier

  • Martin WerleEmail author
  • Hirofumi Takeuchi


Enzymatic degradation of various hydrophilic macromolecules including peptide- or protein drugs by enzymes present in the gastrointestinal tract can be regarded as one main reason for their poor bioavailability after peroral administration. Within the current chapter, strategies to overcome the so-called enzymatic barrier are described. Besides formulations that can protect the drug from enzymatic digestion via, e.g., drug encapsulation and chemical modifications of the drug itself, an emphasis has been put forward on enzyme inhibitors.


Ethylene Glycol Tetraacetic Acid Ethylene Glycol Tetraacetic Acid Ethylene Glycol Tetraacetic Acid Oral Drug Delivery Modify Amino Acid 
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© Springer Science+Business Media, LLC 2009

Authors and Affiliations

  1. 1.Laboratory of Pharmaceutical Engineering, Department of Drug Delivery Technology and ScienceGifu Pharmaceutical UniversityGifuJapan

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