Mucoadhesive Drug Delivery Systems

Mucoadhesive drug delivery systems are comprised of administration of drug across the mucosal membrane using a mucoadhesive/bioadhesive polymer through various noninvasive routes such as peroral, ocular, buccal, nasal, stomach, intestinal, colon, vaginal, rectal, cervical or vulval. The drug delivery systems, which have made use of chitosan as a carrier for administration through various routes, have been represented in Table 2.2. 

The mucoadhesive property of chitosan has been exploited in designing various mucoadhesive dosage forms as it prolongs the contact time of the active drug at its requisite site of absorption, thus often enhancing its bioavailabihty and exhibiting a sustained drug release effect [112-114]. 

Chitosan, being cationic in nature, interacts with the negatively charged mucosal surface, yielding mucoadhesive property due to strong electrostatic interaction [115]. 

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In the gastrointestinal tract, a mucoadhesive drug delivery system provides advantages in prolonging the residence time of devices. The use of pH-sensitive bioadhesive polymers has been proposed [26], An extensive review of pH-sensi-tive hydrogels is given by Brpndsted and Kopecek [27],... 

The failure in increasing residence time of mucoadhesive systems in the human intestinal tract has led scientists to the evaluation of multifunctional mucoadhesive polymers. Research in the area of mucoadhesive drug delivery systems has shed light on other properties of some of the mucoadhesive polymers. One important class of mucoadhesive polymers, poly(acrylic acid) derivatives, has been identified as potent inhibitors of proteolytic enzymes [72-74]. The interaction between various types of mucoadhesive polymers and epithelial cells has a direct influence on the permeability of mucosal epithelia by means of changing the gating properties of the tight jrmctions. More than being only adhesives, some mucoadhesive polymers can therefore be considered as a novel class of multifunctional macromolecules with a number of desirable properties for their use as delivery adjuvants [72,75]. 

Wang, J., et al. 2000. Positively charged gelatin microspheres as gastric mucoadhesive drug delivery system for eradication of H. pylori. Drug Deliv 1 231. 

Mucus. The cells of internal epithelia throughout the body are surrounded by an intercellular ground substance known as mucus. The principal components of mucus are complexes composed of proteins and carbohydrates. These complexes may be free of association or may be attached to certain regions on cell surfaces. This matrix may play a role in cell-cell adhesion, as well as acting as a lubricant, allowing cells to move relative to one another.99 Moreover, mucus is believed to play a role in bioadhesion of mucoadhesive drug delivery systems.100... 

Takeuchi H, Thongborisute J, Matsui Y, Sugihara H, Yamamoto H, Kawashima Y (2005b) Novel mucoadhesion tests for polymers and polymer-coated particles to design optimal mucoadhesive drug delivery systems. Adv Drug Del Rev 57(11) 1583-1594... 

A mucoadhesive drug delivery system can enhance oral drag absorption in a variety of ways, by ... 

Ugwoke, M. I., Exaud, S., Van Den Mooter, G., Verbeke, N., and Kinget, R. (1999), Bioavailability of apomorphine following intranasal administration of mucoadhesive drug delivery systems in rabbits, Eur. J. Pharm. Sci., 9,213-219. 

Llabot JM, Manzo RH, Allemandi DA. Drug release from carbomer carbomer sodium salt matrices with potential use as mucoadhesive drug delivery system. Int J Pharm 2004 276 59-66. 

Glyceryl monooleate gels in excess water, forming a highly ordered cubic phase that can be used to sustain the release of various water-soluble drugs.It is also the basis of mucoadhesive drug delivery systems. 

Akiyama, Y., Nagahara, N. Novel formulation approaches to oral mucoadhesive drug delivery systems. In Bioadhesive Drug Delivery Systems—Fundamentals, Novel Approaches and Development. Mathiowitz, E., Chickering, D.E., Lehr, C.M. (Eds.) Marcel Dekker, New York, 1998, p. All. 

Ahuja, Alka, Roop K. Khar, Javed Ali. Mucoadhesive drug delivery systems. 7)n/g Development and Industrial Pharmacy 23, no. 5 (1997), 489-515. 

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