Mixed matrix microspheres for improving storage quality of red blood cells via removing lactate metabolites

The objective of this study is to optimize the storage conditions for red blood cells (RBCs) by reducing levels of metabolic byproducts lactic acid. Herein, we develop a novel mixed matrix microsphere (MMM) for removing lactic acid. A polysulfone porous shell was encapsulating polystyrene ion exchange resins, providing transport channels for lactic acid diffusion and adsorption while protecting red blood cells from intense contact. The MMM exhibited a highly porous surface with exceptional lactic acid adsorption capacity (287.3 mg·g −1 ) and excellent hemocompatibility that inhibits thrombosis and production of inflammatory factors upon long-term contact with blood. Consequently, these microspheres were tested for blood containers storage for over 35 days. The significant reduction in lactic acid levels within the bloodstream helps maintaining an optimal pH environment for normal RBC metabolism and preserves their oxygen-carrying capacity over time without rapid decay. In summary, MMM shows its practicality for improving long-term storage quality of RBCs while mitigating symptoms associated with transfusion-transmitted infectious diseases.