Mucoadhesive drug delivery systems

Flávia Chiva Carvalho,Marcos Luciano Bruschi,Maria Palmira Daflon Gremião,Raul Cesar Evangelista

doi:10.1590/s1984-82502010000100002

Abstract

Drug actions can be improved by developing new drug delivery systems, such as the mucoadhesive system. These systems remain in close contact with the absorption tissue, the mucous membrane, releasing the drug at the action site leading to a bioavailability increase and both local and systemic effects. Mucoadhesion is currently explained by six theories: electronic, adsorption, wettability, diffusion, fracture and mechanical. Several in vitro and in vivo methodologies are proposed for studying its mechanisms. However, mucoadhesion is not yet well understood. The aim of this study was to review the mechanisms and theories involved in mucoadhesion, as well as to describe the most-used methodologies and polymers in mucoadhesive drug delivery systems.

Highlights

The effect of a drug can be reinforced as a result of the development of new release systems
During the 1980s, this concept began to be applied to drug delivery systems
An extensive review on mucoadhesive systems was compiled by Andrews, Laverty and Jones (2008)

Summary

INTRODUCTION

The effect of a drug can be reinforced as a result of the development of new release systems. It is believed that the adhesion force increases with the degree of penetration of the polymer chains (Mathiowitz, Chickering, Lehr, 1999) This penetration rate depends on the diffusion coefficient, flexibility and nature of the mucoadhesive chains, mobility and contact time (Hägerström, 2003; Huang et al, 2000; Lee, Park, Robinson, 2000; Smart, 2005). These novel multifunctional mucoadhesive systems are classified as second generation polymers (Lee, Park, Robinson, 2000) They are an alternative to non-specific bioadhesives (Smart, 2005) because they bind or adhere to specific chemical structures on the cell or mucus surface. The percent adhesion rate of the release system onto the sac is determined by subtracting the residual mass from the initial mass (Santos et al, 1999)

METHODS

Rheological methods

CONCLUSIONS