Chapter 13 - Carboxymethyl chitosan in advanced drug-delivery applications

Abstract

Chitosan (CS) is a biocompatible, biodegradable, nontoxic, and low-cost biomaterial, and, therefore, can be significantly used in the formulation of various drug-delivery systems, in tissue engineering applications, fabrication of various medical devices, and also in agricultural applications. However, the poor solubility of CS in alkaline or aqueous media has constrained its uses in the biomedical and pharmaceutical fields. Additionally, one of the most important drawbacks of CS, rather than poor solubility, is its fast adsorption and extended swelling rate in the aqueous media, which ultimately causes faster drug release. Further, to overcome these issues, CS-based derivative like carboxymethyl chitosan (CMCS) is used. Due to their immense biocompatibility, mucoadhesiveness, less toxicity, and competence to produce gels, these CMCS are highly useful for biomedical and pharmaceutical applications. It has been observed that involvement of a carboxymethyl group (–CH2–COOH) through chemical modifications is one of the most favorable techniques for enhancing the solubility of CS. Moreover, CMCS is proficiently used as an alternative source of CS for fabricating biomaterials and targeted drug-delivery systems. Also, CMCS efficiently interacts with the cells/tissues, and hence helps for cellular growth, tissue regeneration, cosmetics, and wound healing. In this review, we have tried to summarize the therapeutic applications of CMCS and its derivatives in drug-delivery approaches like antiinfective, anticancer, antitumor, antioxidant, antiinflammatory, and in various biomedical applications, including bone/cartilage tissue engineering, wound healing, bioimaging, targeted delivery, and cosmetics.