Mucoadhesive hydrogels

By definition, mucoadhesive hydrogels are a elass of polymeric biomaterials that exhibit the basic characteristic of an hydrogel to swell by absorbing water and interacting by means of adhesion with the mucus that covers epithelia. 

The eoneept of mueoadhesion in drug delivery was introduced in the field of controlled-release drug delivery systems in the early 1980s [2,3]. Thereafter, several researchers have focused on the investigations of the interfacial phenomena of mucoadhesive hydrogels (and of other type mucoadhesive compounds) with the mucus. Several techniques of studying these interactions were evaluated both in vitro and... 

Tensiometry Force required to dislodge two surfaces, one coated with mucus, the other solid dosage form consisting of mucoadhesive hydrogel... 

Specific type of mucoadhesive compounds, like lectins, have been evaluated to solve the difficulties presented by conventional mucoadhesive hydrogel systems, for instance in the gastrointestinal route. Since these compoimds do not belong to the class of hydrogels, they are not extensively discussed here. 

The electronic theory is based on the assumption that the mucoadhesive hydrogel and the target biological tissue have different electronic structures. When two materials come into contact with each other, electron transfer occurs, causing the formation of a double layer of electrical charge at the bioadhesive-biological interface. The bioadhesive force is believed to be due to attractive forces across this electrical double layer. 

In this article a large number of polymer modifications have been described as novel drug delivery platforms, being second-generation mucoadhesive hydrogels. These polymers, both as safe absorption enhancers [75] or as improved mucoadhesive hy-... 

Maya Thanou, Ph.D. Division of Pharmaceutical Technology, Leiden/Amsterdam Center for Drug Research, Leiden University, Leiden, The Netherlands Mucoadhesive Hydrogels in Drug Delivery... 

By definition, mucoadhesive hydrogels are a class of polymeric biomaterials that exhibit the basic character- 2. 

A mucoadhesive hydrogel used as a drug delivery system should... 

During the last decade research was particularly focused on the delivery of mucoadhesive dosage forms in the gastrointestinal tract, which is the most favorable route of delivery with regard to patient compliance and ease of application. For this reason microparticulate formulations, consisting of mucoadhesive hydrogels. 

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