{Reference Type}: Journal Article {Title}: O-carboxymethyl chitosan in biomedicine: A review. {Author}: Chen L;Xie Y;Chen X;Li H;Lu Y;Yu H;Zheng D; {Journal}: Int J Biol Macromol {Volume}: 275 {Issue}: 0 {Year}: 2024 Aug 28 {Factor}: 8.025 {DOI}: 10.1016/j.ijbiomac.2024.133465 {Abstract}: O-carboxymethyl chitosan (O-CMC) is a chitosan derivative produced through the substitution of hydroxyl (-OH) functional groups in glucosamine units with carboxymethyl (-CH2COOH) substituents, effectively addressing the inherent solubility issues of chitosan in aqueous solutions. O-CMC has garnered significant interest due to its enhanced solubility, elevated viscosity, minimal toxicity, and advantageous biocompatibility properties. Furthermore, O-CMC demonstrates antibacterial, antifungal, and antioxidant characteristics, rendering it a promising candidate for various biomedical uses such as wound healing, tissue engineering, anti-tumor therapies, biosensors, and bioimaging. Additionally, O-CMC is well-suited for the fabrication of nanoparticles, hydrogels, films, microcapsules, and tablets, offering opportunities for effective drug delivery systems. This review outlines the distinctive features of O-CMC, offers analyses of advancements and future potential based on current research, examines significant obstacles for clinical implementation, and foresees its ongoing significant impacts in the realm of biomedicine.