Polysaccharide-Based Injectable Bioadhesive Hydrogel for Local Arterial Occlusion

Injectable hydrogels offer a promising material platform for local filling and sealing by enabling needle delivery, in situ network formation, and conformal adaptation to irregular biological spaces. In vascular occlusion applications, effective material localization requires cohesive post-injection network recovery and stable retention at the target site after blood flow restoration. Here, we developed a polysaccharide-based injectable bioadhesive hydrogel, termed CCOD-gel, composed of chitosan, catechol-modified chitosan, oxidized dextran, and 3,4-dihydroxybenzaldehyde through dynamic Schiff-base crosslinking. The dynamic network enabled shear-thinning injection and rapid post-injection recovery, whereas catechol and aldehyde groups contributed to interfacial anchoring to vascular tissue. Together with mild pro-coagulant activity, low hemolysis, and favorable biological compatibility, CCOD-gel was evaluated in rabbit and porcine arterial models. In a rabbit femoral artery model, CCOD-gel achieved local arterial occlusion and maintained loss of detectable Doppler flow signals for up to 27 days, accompanied by luminal fibrosis. In porcine arterial models of different calibers, the hydrogel remained localized after injection and resisted subsequent arterial washout. These findings establish CCOD-gel as a proof-of-concept bioadhesive polysaccharide hydrogel strategy for vascular occlusion in locally accessible arterial settings.