This thesis explores the potential of collagen-based hydrogels as biomimetic materials for biomedical applications, with a dual focus on mechanical characterization and magnetic resonance imaging (MRI) assessment. Collagen is the most abundant structural protein in the human body and a key component of the extracellular matrix, where it provides both mechanical support and biochemical cues essential for cell adhesion, migration, and differentiation. Alterations in collagen concentration, distribution, or organization are strongly associated with pathological processes such as fibrosis and cancer. For instance, in breast cancer, abnormal collagen deposition and stiffening of the surrounding matrix are recognized as hallmarks of tumor progression and metastasis.