Emerging trends in chitosan based colloidal drug delivery systems: A translational journey from research to practice

Abstract

Chitosan, a natural polymer derived from chitin, has garnered significant interest in pharmaceutical and biomedical applications due to its distinctive properties, such as controlled drug release, mucoadhesive capabilities, in situ gelling property, enhancement of permeation, and efflux pump inhibitory effect. In this review, various types of chitosan based colloidal drug delivery systems such as vesicular, and particulate systems were discussed along with their role in pre-clinical biomedical applications. Some important clinical applications of chitosan-based drug delivery systems in treating major chronic diseases were also discussed. Using Chitosan in delivery of drugs and gene therapy had many beneficial outcomes, however, obtaining clinical acceptance and regulatory approval requires a careful approach for proving efficacy and safety. In order to present the current status of chitosan-based drug delivery systems, filled patents employing chitosan derivatives were also part of this review. This will help forward the use of chitosan-based drug delivery system from research to practice. Finally, the future prospects for chitosan-based delivery systems were discussed.

Introduction

Chitosan, a natural polysaccharide extracted from chitin, is occasionally referred as deacetylated chitin. Chitin is one of the most significant biopolymers, playing a vital role in the carbon and nitrogen biogeochemical cycles, particularly in aquatic ecosystems (unes & Philipps-Wiemann, 2018). It is produced by various invertebrate animals and represents the principal exoskeleton constituent in arthropods, including crustaceans and insects. Besides animals, several microorganisms have been identified as sources of chitin, such as fungi, bacteria, and protozoa. It is assumed that annual synthesis of chitin equals that of cellulose and thus it is a potential source for a new functional material with high possibilities of applications in different fields, with recent advancements in chitin chemistry being particularly exceptional (Terkula Iber et al., 2022). Chitosan is composed of β-(1-4)-linked d-glucosamine and N-acetyl-d-glucosamine randomly distributed within the polymer (Soni et al., 2023).

Their application primarily as excipients in drug formulations and drug delivery systems, focusing on replacing potentially harmful compounds with natural alternatives. This transition was met with optimism, and the pharmaceutical industry quickly recognized the benefits of utilizing chitosan. Chitosan and its derivatives have remained a subject of extensive research, attracting both the scientific community and industry players. Key areas of interest revolve around chitosan’s bioactivities. Another study highlights its crucial properties and advantages, while derivatisation expanded its application possibilities and reduced toxicity (Bernkop-Schnürch & Dünnhaupt, 2012).

In the pharmaceutical realm, chitosan’s significant properties include controlled drug release, mucoadhesive characteristics, in situ gelling abilities, transfection enhancement, and permeation enhancement. Notably, chitosan forms stable complexes with Deoxyribonucleic Acid (DNA) and Ribonucleic Acid (RNA)-based drugs, contributing to efficient transfection. It also inhibits efflux pumps like other polysaccharides. Chitosan and its derivatives can take various forms, such as solutions, gels, tablets, capsules, films, fibres, and sponges, allowing versatile administration routes like oral, ocular, nasal, vaginal, buccal, parenteral, intravesical, and transdermal (Ma et al., 2022) (Yin et al., 2025) (Narayanan et al., 2022) (Arpa et al., 2023) (Conde et al., 2024) (Nieto González et al., 2024). They are also applicable in implantable and injectable drug delivery, detailed in various preparation methods (Ali & Ahmed, 2018).