HEPARIN IMMOBILIZATION OF THE VASCULAR GRAFTS BY LAYER-BY-LAYER (LBL) ASSEMBLY TECHNIQUE TO IMPROVE THROMBOGENICITY

Decellularized vascular grafts hold potential for small-diameter vascular reconstruction owing to the ECM integrity maintained and appropriate dimensions. However, the thrombogenicity of tissue-derived grafts represents a notable limitation for clinical application. This study focuses on assessing the effectiveness of heparin immobilization on cross-linked decellularized vascular grafts prepared from porcine carotid arteries. The Layer-by-Layer (LbL) assembly technique was applied to immobilize heparin on the graft surface to improve hemocompatibility. Following LbL treatment, the grafts were examined for heparin content and surface morphology using scanning electron microscopy (SEM). To assess their potential for vascular implantation, the biomechanical properties and hemocompatibility were further evaluated. SEM observations and heparin quantification confirmed successful heparin immobilization. Biomechanical testing was measured and found to be suitable for graft applications. In terms of hemocompatibility, in vitro anticoagulant activity assessment revealed a thromboresistant surface on the luminal surface of the grafts. In addition, hemolysis rates remained within the non-hemolytic threshold as defined by ISO 10993-4. In summary, the Layer-by-Layer heparin immobilization method effectively immobilized heparin onto reinforced decellularized vascular grafts, enhanced hemocompatibility, and represents a promising approach for the development of xenogeneic vascular graft materials.