Mucoadhesive matrix tablets

Arora G, Malik K, Singh I, Arora S. Formulation and evaluation of controlled release mucoadhesive matrix tablets Assessment of myrrh oleo gum resin as a natural pharmaceutical excipient. Int J Pharm Sci Drug Res. 3 (2) 84-88, 2011. 

Langoth et al. [86] studied the properties of matrix-based tablets containing the novel pentapeptide leu-enkephalin (Tyr-Gly-Gly-Phe-Leu) that has been shown to have pain-modulating properties. The matrix-based tablets were made with the thiolated polymer PCP. The covalent attachment of cysteine to the anionic polymer PCP leads to an improvement of the stability of matrix tablets, enhances the mucoadhesive properties, and increases the inhibitory potency of PCP towards buccal enzymes. All these factors lead to stability of the peptide and a controlled drug release for the peptide was obtained for more than 24 h. Also, the tablets based on thiolated PCP remained attached on freshly excised porcine mucosa 1.8 times longer than the corresponding unmodified polymer. 

Extracted from the stem of different Commiphora spp.—C. myrrha (Nees) Engl., C. habessinica (O. Berg) Engl, C. wightii (Arn.) Bhandari—Burseraceae family, myrrh oleo gum resin has been known since ancient times due to its medicinal properties [397], In the drug industry, myrrh oleo gum resin may be used as directly compressible tablet excipient and release retardant [398] and as binder, release retardant and mucoadhesive for the preparation and evaluation of controlled release bioadhesive matrix tablets of domperidone [399]. 

Bioadhesive tablets can be made by the compression of polymers or can consist of a matrix base or bilayers, with an impermeable backing layer covering the layer with the drug and the mucoadhesion polymer. Examples of these systems are discussed below. 

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