Advances in Stimuli‐Responsive Chitosan Hydrogels for Drug Delivery Systems

Abstract

Sustainable and controllable drug transport is one of the most efficient ways of disease treatment. Due to high biocompatibility, good biodegradability, and low costs, chitosan and its derivatives are widely used in biomedical fields. Specifically, chitosan hydrogel enables drugs to pass through biological barriers because of their abundant amino and hydroxyl groups that can interact with human tissues. Moreover, the multi‐responsive nature (pH, temperature, ions strength, and magnetic field, etc.) of chitosan hydrogels makes precise drug release a possibility. Here, the synthesis methods, modification strategies, stimuli‐responsive mechanisms of chitosan‐based hydrogels, and their recent progress in drug delivery are summarized. Chitosan hydrogels that carry and release drugs through subcutaneous (dealing with wound dressing), oral (dealing with gastrointestinal tract), and facial (dealing with ophthalmic, ear, and brain) are reviewed. Finally, challenges toward clinic application and the future prospects of stimuli‐responsive chitosan‐based hydrogels are indicated.

Tragacanth gum-based hydrogels for drug delivery and tissue engineering applications

“…The pH-responsive nature of hydrogels derived from tragacanth gel opens up diverse applications. In drug delivery systems, the controlled release of therapeutic agents can be achieved by exploiting the pH-dependent swelling behavior (Xia et al, 2023). Additionally, these hydrogels find applications in sensors, responsive coatings, and environmental remediation, where pH changes can be leveraged for specific functionalities.…”

Preparation of Biodegradable Chitosan Semi-Interpenetrating Network Hydrogel and Its Application for Gastric Retention

“…The dried hydrogel can be taken orally, and upon contact with gastric uid, its network structure rapidly absorbs water, causing the hydrogel to swell and remain in the stomach for an extended period without rapid emptying. Chitosan molecules interpenetrate within the network structure, forming hydrogen bonds [11], which enhance the mechanical performance of the hydrogel, preventing easy disruption by gastric peristalsis.…”

Antioxidative, Anti-Inflammatory, Antibacterial, Photo-Cross-Linkable Hydrogel of Gallic Acid–Chitosan Methacrylate: Synthesis, In Vitro, and In Vivo Assessments

“…Similar to many other commonly used natural polymers, such as gelatin, collagen, and hyaluronic acid, CS is cost-effective with good biocompatibility and unique antibacterial activity, making it attractive for a wide range of applications in the biomedical field. Especially, CS-based hydrogels have gained increasing attention for drug delivery, wound healing, health monitoring, and bioadhesives …”