Applications of polysaccharides in topical and transdermal drug delivery: A recent update of literature

Abstract The main aim of transdermal drug delivery (TDD) is to deliver a specific dose of drug across the skin and to reach systemic circulation at a controlled rate. On the other hand skin is the target for topical drug delivery. Mentioned drug delivery systems (DDS) have numerous advantages compared to oral and parenteral routes. Avoidance of first-pass metabolism, prevent drug degradation due to harsh environment of the stomach, allow controlled drug delivery, provide patient compliance, and pain-free administration are a few of them. To achieve all of them, a DDS with suitable polymer is the primary requisite. Based on the recent trends, natural polymers have been more popular in comparison to synthetic polymers because the former possesses favourable properties including nontoxic, biodegradable, biocompatible, low cost, sustainable and renewable resources. In this context polysaccharides, composed of chains of monosaccharides bound together by glycosidic bonds, have been successfully employed to augment drug delivery into and across the skin with various formulations such as gel, membrane, patches, nanoparticles, nanofibres, nanocomposite, and microneedles. In this chapter, various polysaccharides such as cellulose, chitosan, and their semisynthetic derivatives, alginate, pectin, carrageenan etc, were discussed with their diverse topical and TDD applications. In addition, various formulations based on polysaccharides and limitations of polysaccharides were also briefly discussed.

摘要 经皮给药（Transdermal Drug Delivery, TDD）的核心目标是通过皮肤递送特定剂量的药物，并以可控速率进入体循环；另一方面，皮肤亦是局部给药的作用靶点。上述给药系统（Drug Delivery Systems, DDS）相较于口服与注射给药途径，具备诸多优势：具体包括避免首过代谢、防止药物因胃部严苛的化学环境发生降解、实现可控给药、提升患者顺应性以及无痛给药等。要达成上述全部优势，搭载适宜聚合物的给药系统是核心必要条件。从当前研究趋势来看，天然聚合物相较于合成聚合物更受青睐，因为前者具备无毒、可生物降解、生物相容性佳、成本低廉以及可持续可再生等优良特性。在此背景下，由通过糖苷键连接的单糖链构成的多糖已被成功应用于多种制剂形式中，以增强药物经皮递送与透皮吸收效果，这些制剂包括凝胶、膜剂、贴剂、纳米粒、纳米纤维、纳米复合材料以及微针等。本章将探讨多种多糖及其在局部给药与经皮给药中的多样化应用，所涉及的多糖包括纤维素、壳聚糖及其半合成衍生物、藻酸盐、果胶、角叉菜胶等。此外，本章还将简要探讨基于多糖的各类制剂以及多糖本身存在的局限性。