Preparation of Platelet Membrane‐Coated Gelatin Nanoparticle Toward Alternative to Platelet Preparation

Platelets play a critical role in hemostasis and tissue repair; however, their short shelf life of approximately four days poses a major challenge to their supply. This limitation underscores the need for long-term storage alternatives. In this study, we developed and characterized platelet membrane-coated gelatin nanoparticles (PL-GNPs) as potential platelet substitutes. PL-GNPs were prepared by coating gelatin nanoparticles (GNPs) with platelet-derived membrane vesicles. Cryo-electron microscopy revealed the formation of a core-shell structure, and immunoblotting demonstrated that key platelet surface proteins, CD41 and CD61, were preserved on the PL-GNP surface in the same orientation as in platelets. The membrane coating improved the stability of the nanoparticles against collagenase-dependent degradation. Moreover, PL-GNPs bound effectively to fibrinogen, an essential interaction in thrombus formation, and retained this function even after one month of storage at 4°C. Collectively, these findings indicate that PL-GNPs recapitulate the critical structural and functional properties of native platelets and hold promise as a stable, long-term storable alternative to conventional platelet preparations for therapeutic use.