Carbohydrate polymer derivatives as gastrointestinal pH-responsive oral drug delivery systems: A review

Abstract

PH-responsive carbohydrate polymers have gained significant attention as promising candidates for next-generation oral drug delivery systems. This review focuses on the use of pH-sensitive carbohydrate polymers as a platform for controlled drug delivery. The unique ability of these polymers to undergo a conformational or structural change in response to specific pH ranges makes them ideal for targeted drug release. The gastrointestinal tract, with its distinct pH environments ranging from the highly acidic stomach to the neutral small intestine, presents a perfect scenario for these intelligent delivery systems. The design principles of these systems, including the chemical modification of natural carbohydrate polymers and the synthesis of new pH-sensitive materials, are explored. Furthermore, this review summarizes recent advancements and challenges in the application of carbohydrate polymers for oral drug delivery, particularly in enhancing drug bioavailability, protecting acid-labile drugs, and enabling site-specific release in the colon. The review concludes by highlighting the immense potential of these biocompatible and biodegradable materials in developing advanced, patient-friendly pharmaceutical formulations. In addition, the primary limitations of these materials are discussed with respect to enzymatic degradation, scaling up, cost-effectiveness, and regulatory approval.

Keywords

Carbohydrate polymer derivatives / Drug delivery systems / pH-sensitivity

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