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Current decellularization methods often rely on harsh chemicals compromising the extracellular matrix (ECM) biochemical structure, particularly in soft tissues like pancreas. Supercritical carbon dioxide (scCO₂) offers a sustainable, non-toxic alternative, preserving structural and biochemical integrity, while improving immune tolerance [1]. This study establishes an integrated scCO₂-based workflow for porcine pancreas decellularization and sterilization, aiming at developing an immunocompetent decellularized ECM (dECM) platform for diabetes cell-based therapies. Pancreas decellularization was achieved using a scCO₂-assisted method (scCO2-dECM) and compared with a conventional detergent-based protocol. Its efficiency and ECM preservation were assessed through DNA quantification, histology (H&E, Masson’s Trichrome, Alcian Blue), SEM/TEM, biochemical assays (glycosaminoglycans (GAGs), collagens) and proteomics. ScCO2-assisted sterilization was validated through turbidity assay. Pyrogenic safety was studied through endotoxin quantification. Cytotoxicity was evaluated following ISO 10993-5:2009 through metabolic activity, proliferation assays, and immunofluorescence imaging. Both methods achieved DNA levels below 50 ng/mg of dry tissue [2]. However, scCO2-dECM preserved higher GAGs content, with enhanced collagen-network preservation. Proteomics revealed that scCO₂-dECM better preserves functional, pancreas- and insulin pathway-related proteins, along with elastic fibers, indicating enhanced retention of tissue-specific biomolecules. ScCO₂-assisted decellularization was more effective in reducing endotoxin content (0.027 EU/mg in scCO₂ vs. 0.413 EU/mg in detergent-treated samples). ScCO₂ sterilization ensured Bacillus subtilis inactivation. Non-cytotoxicity was confirmed by metabolic activity and cell proliferation over time. DAPI/Phalloidin staining confirmed normal morphology and cytoskeleton organization. Ongoing study investigates whether Damage-Associated Molecular Patterns (DAMPs) trigger macrophage inflammation. Overall, scCO₂ enables fast and efficient decellularization, preserving dECM integrity and showing cytocompatibility. This greener approach delivers functional pancreatic dECM, as potential platform towards pancreatic tissue engineering for diabetes.