Highly curved and flexible SiO₂ fiber sponge via turbulence spinning for efficient and portable plasma/serum separation

Blood analysis is essential for managing critically ill patients, yet plasma/serum separation in point-of-care testing (POCT) remains centrifugation-dependent, hindering utility in resource-limited settings. Conventional filtration materials suffer from poor mechanical strength, fragile structures, and suboptimal separation performance. Herein, we fabricate a silica microfiber sponge (Turb-SiO₂) with a 3D disordered network via a turbulence spinning technique. The material exhibits exceptional flexibility, retaining >64% initial stress after 2500 compression cycles, and superior breathability (99.51% air permeability, 0.12 mm H₂O pressure drops) under compression. The Turb-SiO₂ achieves efficient plasma separation with filtrate hemoglobin at 15.7 mg dL^-1, matching centrifugation efficacy and outperforming commercial filters. Its crimped fiber structure minimizes hemolysis by eliminating sharp tips that can damage red blood cells. With advantages in weight, volume, cost and operability, the Turb-SiO₂ offers a high-performance solution for portable low-cost POCT blood separation.