Development of rapid hypoxia-detectable artificial oxygen carriers with a core–shell structure and erythrocyte mimetic shape

Abstract

Human red blood cells (RBCs) play a crucial role in delivering oxygen to tissues, and this function is closely linked to the fate of these cells, including their growth, differentiation, and survival. Inspired by RBCs, we propose a concave-shaped deformable perfluorocarbon-based oxygen carrier (cDFC) with a hypoxia-detectable function, based on a novel (PDMS) thermoplastic elastomer (PDMS-TPE), called a bifunctional cDFC, with a morphology similar to that of human RBCs. We prepared (PFOB)/PDMS-TPE cDFCs via Shirasu porous glass membrane emulsification (SPG ME), while adding tris(4,7-diphenyl-1,10-phenanthroline)ruthenium(II) (Ru(dpp)), platinum(II) octaethylporphine (PtOEP), and platinum(II) octaethylporphine (PtTFPP) to the dispersed phase to be immobilized in the PDMS-TPE shell as oxygen sensors. Among the three oxygen probes, PtOEP-loaded PFOB/PDMS-TPE exhibited the highest sensitivity to the dissolved oxygen concentration, with a K_sv value of 14. The bifunctional cDFCs also exhibited high biocompatibility in vitro, high stability, and negligible leaching of probe molecules in cell culture. Bifunctional cDFCs have potential for precise oxygenation in biomedical applications. Moreover, the illuminance response of cDFCs to a sudden drop of dissolved oxygen was fast, which was supported by numerical predictions using a diffusion equation model. The bifunctional cDFCs showed both rapid oxygen release and absorption and prompt detection of the oxygen concentration based on experiments and mathematical modeling.