Naturally Occurring Polyelectrolytes and Their Use for the Development of Complex-Based Mucoadhesive Drug Delivery Systems: An Overview

Abstract

Biopolymers have several advantages for the development of drug delivery systems, since they are biocompatible, biodegradable and easy to obtain from renewable resources. However, their most notable advantage may be their ability to adhere to biological tissues. Many of these biopolymers have ionized forms, known as polyelectrolytes. When combined, polyelectrolytes with opposite charges spontaneously form polyelectrolyte complexes or multilayers, which have great functional versatility. Although only one natural polycation—chitosan has been widely explored until now, it has been combined with many natural polyanions such as pectin, alginate and xanthan gum, among others. These polyelectrolyte complexes have been used to develop multiple mucoadhesive dosage forms such as hydrogels, tablets, microparticles, and films, which have demonstrated extraordinary potential to administer drugs by the ocular, nasal, buccal, oral, and vaginal routes, improving both local and systemic treatments. The advantages observed for these formulations include the increased bioavailability or residence time of the formulation in the administration zone, and the avoidance of invasive administration routes, leading to greater therapeutic compliance.

Polyelectrolyte Multilayer Films as a Potential Buccal Platform for Drug Delivery

“…Recently, polyelectrolyte complexes of polysaccharides and proteins have been extensively investigated for biomedical applications [18,19]. Chitosan-based complexes have proved to be favorable in various aspects.…”

Biocompatible and Biomaterials Application in Drug Delivery System in Oral Cavity

“…HyA-based scaffolds of bone regenerative are more active and compatible in biological environments with biomimetic mechanisms. HyA as a matrix constituent, particularly sulfated HyA, may promote modulation of cell behavior through many signaling pathways, which leads faster and better bone formations [ 61 ]. HyA-based carriers and scaffolds are formed into colloids or solid shapes.…”

Applications of Chitosan in Surgical and Post-Surgical Materials

“…Among the most frequent diluted acids used to dissolve chitosan, acetic acid, formic acid, hydrochloric acid, and lactic acid can be highlighted, while sulfuric acid and phosphoric acid do not dissolve chitosan [22,23]. Its positive charge in acid media allows chitosan to interact with polyanions through electrostatic interactions [15,21]. In addition, protonated amino groups can interact with the sialic groups of mucin, conferring this polymer the ability to bind mucosal surfaces, directly depending on the degree of deacetylation [16,24,25].…”