Production of oxygen-generating collagen gel and quantitative analysis of oxygen generation ability

Tissue engineering of thick hepatic tissues is limited by an inadequate oxygen supply, which causes hypoxia and cell death. Oxygen-generating materials have emerged to temporarily relieve hypoxia. However, quantitative analysis of their ability to generate oxygen is still lacking, hindering the precise evaluation of their efficacy. In this study, we developed an oxygen-generating collagen gel (oxy CG) containing calcium peroxide (CaO₂) and quantitatively analyzed its oxygen release dynamics by measuring the oxygen generation rate and calculating its volumetric oxygen transfer coefficient (k_La). Using this method, we derived a theoretical threshold for cultivable cell density that was experimentally validated under hypoxic conditions using primary rat hepatocytes (PRHs). Oxy CG sustained oxygen release, while maintaining pH stability, supporting hepatocyte viability and liver-specific functions, such as urea synthesis and albumin secretion, within the predicted cell density range. This study provides a quantitative framework that balances oxygen supply and cellular demand, providing valuable insights for optimizing oxygen delivery in liver tissue engineering to overcome diffusion limitations in 3D constructs and improve clinical applicability.