Fast Expandable Chitosan‐Fibers Cryogel from Ambient Drying for Noncompressible Bleeding Control and In Situ Tissue Regeneration

Abstract

Hemorrhage control, especially noncompressible wound hemostasis, is a tremendous challenge in military injuries and other traumas worldwide. Here, a cryogelation strategy and subsequent solvent exchange are developed for the hydrogen bond-induced self-assembly of chitosan fibers and the production of fast expandable chitosan cryogel. Importantly, the ambient drying process facilitates the repeatable deformation performance of the shape-memory cryogel with a response time of ≈1.7 s. Due to the capillary-like structure of the cryogel and high hydrophilicity, rapid shape recovery is accompanied by 41 times water absorption ability. It is further demonstrated that chitosan cryogel is beneficial for in situ tissue regeneration by taking advantage of the biodegradability and biocompatibility of chitosan. Thus, chitosan cryogels prepared by this simple and benign method should have efficient hemostatic effect on noncompressible bleeding and severe fatal high-pressure hemorrhage.

A 3D‐Printed Cuttlefish Bone Elastomeric Sponge Rapidly Controlling Noncompressible Hemorrhage

“…Taken together, the printed structure with a 30% filling rate was more suited for use as a noncompressible hemostatic material based on its liquid absorptivity and deformability. [ 52 ] The results of anti‐fatigue cyclic compression experiments showed that after 50 compression cycles at a high strain of 60%, the CBES with a 30% filling rate virtually maintained its original volume, indicating the structural stability and effective shape recovery performance of the CBES. Moreover, the compression stress‒strain curves showed that the elastic modulus of the constructs increased with increasing CBp content (Figure 2K).…”

Preparation and Application of Hemostatic Hydrogels

“…Furthermore, the absence of the cryogelation process during freezing compromises the mechanical strength of the structures, thereby restricting their applications in hemostasis. In contrast, the room temperature drying process employed by Qi et al [89] proves to be a more cost-effective and straightforward alternative, yielding a cryogel with favorable mechanical properties.…”

“…In contrast, the room temperature drying process employed by Qi et al. [ 89 ] proves to be a more cost‐effective and straightforward alternative, yielding a cryogel with favorable mechanical properties.…”

Emerging Smart Micro/Nanofiber‐Based Materials for Next‐Generation Wound Dressings

“…Owing to the synergistic effect of microfibers and nanofibers, the obtained cryogel exhibited superior compressibility and fatigue resistance. Based on this strategy, Shi et al [137] conducted ethanol solvent exchange and shape fixation under compression treatments to develop a shapememory CS cryogel, which rapidly expanded to its original shape within 1.7 s upon contact with water. Benefited from hemostatic nature of CS, microporous structure, and rapid water-sucking capability, the cryogel exhibited excellent hemostatic properties, which was demonstrated in the rat liver defect model, rat femoral artery injury model, rabbit axillary artery and rabbit vein complete transection model.…”