Multifunctional Polymeric Excipients in Oral Macromolecular Drug Delivery



More recently polymers exhibiting multifunctional properties such as mucoadhesive, enzyme inhibitory, permeation-enhancing properties and/or high buffer capacity turned out to be a powerful platform for oral delivery of macromolecular drugs. Several polymers are known to exhibit multifunctional properties such as chitosans, polyacrylates and cellulose derivatives. Chemical modification of these well-established polymers including the attachment of enzyme inhibitors, chelating agents or thiol moieties leads to further improvement or enlargement of their multifunctional profile. Delivery system based on multifunctional polymers can protect the incorporated drug from pH- and enzyme-dependent degradation down its way through the GI tract and can provide high drug concentrations at the target site and tight contact with the absorption membrane due to mucoadhesion. Furthermore, sustained or delayed release due to cohesive properties of the polymeric carrier system offers new possibilities for targeted macromolecular drug delivery.


Drug Release Disulphide Bond Permeation Enhancer Incorporated Drug Mucoadhesive Property 


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Copyright information

© Springer Science+Business Media, LLC 2009

Authors and Affiliations

  1. 1.Thiomatrix Forschungs Beratungs GmbHAustria

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