Developing an excellent hemostatic material with good biocompatibility and high blood absorption capacity for rapid hemostasis of deep non-compressible hemorrhage remains a significant challenge. Herein, a novel conjugate electrospinning strategy to prepare an ultralight 3D gelatin sponge consisting of continuous interconnected nanofibers. This unique fluffy nanofiber structure endows the sponge with low density, high surface area, compressibility, and ultrastrong liquid absorption capacity. In vitro assessments show the gelatin nanofiber sponge has good cytocompatibility, high cell permeability, and low hemolysis ratio. The rat subcutaneous implantation studies demonstrate good biocompatibility and biodegradability of gelatin nanofiber sponge. Gelatin nanofiber sponge aggregates and activates platelets in large quantities to accelerate the formation of platelet embolism, and simultaneously escalates other extrinsic and intrinsic coagulation pathways, which collectively contribute to its superior hemostatic capacity. In vivo studies on an ear artery injury model and a liver trauma model of rabbits demonstrate that the gelatin nanofiber sponge rapidly induce stable blood clots with least blood loss compared to gelatin nanofiber membrane, medical gauze, and commercial gelatin hemostatic sponge. Hence, the gelatin nanofiber sponge holds great potential as an absorbable hemostatic agent for rapid hemostasis.

Electrospinning is a versatile strategy for creating nanofiber materials with various structures, which has broad application for a myriad of areas ranging from tissue engineering, energy harvesting, filtration and has become one of the most important academic and technical activities in the field of material science in recent years. In addition to playing a significant role in the construction of two-dimensional (2D) nanomaterials, electrospinning holds great promise as a robust method for producing three-dimensional (3D) aerogels and scaffolds. This article reviews and summarizes the recent advanced methods for fabricating electrospun three-dimensional nanofiber aerogels and scaffolds, including gas foaming, direct electrospinning of 3D nanofibrous scaffold, short nanofibers assembling into 3D aerogels/scaffolds, 3D printing, electrospray, origami and cell sheet engineering, centrifugal electrospinning, and other methods. Besides, intriguing formation process, crosslinking pathway, properties, and applications of 3D aerogels and scaffolds are also introduced. Taken together, these aerogels and scaffolds with various excellent features present tremendous potential in various fields.

Diabetic wound (DW) healing is a major clinical challenge due to multifactorial complications leading to prolonged inflammation. Electrospun nanofibrous (NF) membranes, due to special structural features, are promising biomaterials capable to promote DW healing through the delivery of active agents in a controlled manner. Herein, we report a multifunctional composite NF membrane loaded with ZnO nanoparticles (NP) and oregano essential oil (OEO), employing a new loading strategy, capable to sustainedly co-deliver bioactive agents. Physicochemical characterization revealed the successful fabrication of loaded nanofibers with strong in vitro anti-bacterial and anti-oxidant activities. Furthermore, in vivo wound healing confirmed the potential of bioactive NF membranes in epithelialization and granulation tissue formation. The angiogenesis was greatly prompted by the bioactive NF membranes through expression of vascular endothelial growth factor (VEGF). Moreover, the proposed NF membrane successfully terminated the inflammatory cycle by downregulating the pro-inflammatory cytokines interleukin −6 (IL-6) and matrix metalloproteinases-9 (MMP-9). In vitro and in vivo studies revealed the proposed NF membrane is a promising dressing material for the healing of DW.

Zinc oxide nanoparticles (ZnO NPs) are known for their antibacterial, antioxidant, and anti-inflammatory activities.

Repairing irregular-shaped bone defects poses enormous challenges. Scaffolds that can fully fit the defect site and simultaneously induce osteogenesis and angiogenesis hold great promise for bone defect healing. This study aimed to produce superelastic organic/inorganic composite aerogel scaffolds by blending silica nanofibers (SiO 2 ) and poly (lactic acid)/gelatin (PLA/gel) nanofibers; the content of SiO 2 nanofibers is varied from 0-60 wt% (e.g., PLA/gel, PLA/gel/SiO 2 -L, PLA/gel/SiO 2 -M, and PLA/gel/SiO 2 -H for 0%, 20%, 40%, and 60% of SiO 2 nanofibers, respectively) to produce a range of scaffolds. The PLA/gel/SiO 2 -M scaffold has excellent elasticity and good mechanical properties. In vitro experiments demonstrate that the silicon ions released from PLA/gel/SiO 2 -M scaffolds promote the differentiation of rat bone marrow-derived mesenchymal stem cells into osteoblasts, enhancing alkaline phosphatase activity and bone-related genes expressions. The released silicon ions also promote the proliferation of human umbilical vein endothelial cells and the expression of vascular endothelial growth factors, thereby promoting angiogenesis. The assessment of these scaffolds in a calvarial defect model in rats shows good potential of PLA/gel/SiO 2 -M to induce bone regeneration as well as promote osteogenesis and angiogenesis. Overall, these organic/inorganic composite scaffolds have good biological activity, which may have broad applications for tissue engineering.