All-natural aerogel of nanoclay/cellulose nanofibers with hierarchical porous structure for rapid hemostasis

Developing an effective and user-friendly hemostatic agent is highly desired in the treatment of hemorrhage. Inspired by the natural nanostructure and abundant hydroxyl groups of cellulose and clay minerals, we designed an aerogel (HNTs/TOCNs) composed of halloysite nanotubes (HNTs) and TEMPO-oxidized cellulose nanofibers (TOCNs) with a hierarchical porous structure for the treatment of bleeding, using a simple and environmentally friendly self-assembly method. TOCNs formed a three-dimensional porous scaffold with excellent water-holding capacity. The incorporation of HNTs enhanced the hemostatic efficiency and mechanical properties of the 3D framework. The large interlayer spaces and wide channels within the HNTs/TOCNs aerogel provided rapid passage for blood, facilitating blood concentration and offering ample room for interactions between the HNTs/ TOCNs aerogel and platelets, erythrocytes, and coagulation factors, thereby promoting hemostasis. Benefiting from the natural hemostatic properties and well-designed structure, the HNTs/TOCNs aerogel displayed excellent hemostatic performance both in vitro and in vivo. Notably, the hemostatic time of HNTs/TOCNs-2 was only 74 +/- 8 s, which is approximately 50% shorter than the blank control (151 +/- 20 s) in liver femoral artery injury model. This design of an HNTs/TOCNs aerogel presents a unique opportunity to enhance hemostatic efficacy by synergizing the advantages of natural materials.