Antibacterial and thermosensitive chitosan-g-poly(N-isopropylacrylamide) copolymer hydrogel containing tannic acid: An injectable therapy for bleeding control

Developing advanced wound dressings improves tissue repair and reduces recovery times. This study introduces a thermo-sensitive hydrogel composed of Chitosan-g-poly (N-isopropylacrylamide) and Tannic acid (CS-PNIPAm-TA), synthesized and characterized using Fourier Transform Infrared Spectroscopy (FTIR) and thermal analysis to confirm successful copolymerization and tannic acid integration. Swelling tests indicated a high capacity for blood absorption, supporting its potential for wound exudate management. Antibacterial testing confirmed the hydrogel's efficacy, with more substantial antibacterial effects observed at higher tannic acid concentrations. Cytotoxicity assessments demonstrated over 90 % cell viability, indicating biocompatibility and fibroblast proliferation. Hemostasis tests in a rat tail injury model showed reduced blood loss and coagulation time, attributed to tannic acid's catalytic effect on the coagulation cascade. In vivo, wound healing assays in a rat model revealed accelerated wound closure compared to controls. These findings suggest that the CS-PNIPAm-TA hydrogel is promising for promoting hemostasis, ensuring biocompatibility, and accelerating wound healing, positioning it as a strong candidate for clinical applications in advanced wound care.