The formulation of materials for 3D bioprinting involves more than meeting isolated technical specifications. It demands a coordinated understanding of flow behavior, structural integrity, and biological performance. In extrusion-based biofabrication, this complexity becomes particularly visible: a printable hydrogel must deform under pressure, recover its shape after deposition, and remain stable long enough to support tissue formation. This thesis addresses that challenge through the development of a hybrid hydrogel based on alginate and xanthan gum. These polymers were selected for their complementary roles: alginate offers biocompatibility and ionic crosslinking capacity, while xanthan gum modulates viscosity and enhances mechanical response. The formulation process was guided by a systematic rheological framework, incorporating both rotational and oscillatory tests to characterize s...