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One of the essential characteristics of an ideal wound dressing is rapid hemostasis.This study aims to investigate the preparation and the characterization of electrospun poly(lactic acid) and halloysite nanotubes (PLA/HNTs) bionanocomposites with either different percentage of pristine and amino-modified HNTs (i.e., 5, 10, and 20 wt%).The effects of HNT's presence, amount, and modification are evaluated on the physicochemical and biological properties which are essential for hemostatic wound dressing. The energy dispersive spectroscopy indicates HNTs are well embedded and dispersed on PLA nanofibers to induce functional interfacial interactions. The addition of HNTs to the PLA in a concentration of 10 wt% improves moisture properties and increases the Young modulus of mats from 26.4 ± 1.66 to 31.62 ± 1.91 and 40.7 ± 1.99 MPa for pristine and modified HNTs, respectively. Also, the surface charge as an influential factor on hemostasis is increased from À39.1 ± 0.3 to À48.4 ± 0.5 and À43.6 ± 0.2 mV for PLA/pristine and modified HNTs bionanocomposites, respectively. Accordingly, blood clotting formation accelerated from 9 to 4 min for the bionanocomposite mat. Furthermore, biological evaluations show that bionanocomposites have suitable cell supporting. It seems that PLA/amino-modified HNTs bionanocomposite have potential application for hemostatic wound healing.

The main challenge in treating injuries is excessive bleeding whereas intervention is required if the body's hemostatic systems fail to control the bleeding. Herein, a novel nanocomposite consisting of poly(lactic acid) (PLA) and poly(amidoamine) (PAMAM) dendrimer functionalized halloysite nanotube (HNT) with a highly porous structure via electrospinning is developed. HNT is functionalized by PAMAM via divergent synthetic routes from zero to third‐generation numbers. The effect of different percentages and generation numbers of PAMAM dendrimer (G1, G2, and G3) functionalized HNT on PLA is studied using physicochemical nanocomposite characteristics. These resultant nanocomposites provide a nanofibrous structure with appropriate physicochemical characteristics such as mechanical properties, surface wettability, and water permeability. The hemostatic assays indicate that nanocomposite with PAMAM G3 functionalized HNT have the quickest blood clotting time due to the abundant amino functional group. Furthermore, the nanocomposites with 10 wt% of nanoparticles significantly promote cellular behavior in vitro. The in vivo study demonstrates that PLA/PAMAM G3 functionalized HNT promotes angiogenesis, collagen deposition, and re‐epithelialization in the wound sites of the rat model, as well as inhibiting inflammatory response. The findings indicate that nanofibrous structure and the presence of dendrimer functionalized HNT have a synergetic effect on the enhanced nanocomposite wound healing performance.

Several ongoing investigations have been founded on the development of an optimized therapeutic strategy for the COVID-19 virus as an undeniable acute challenge for human life. Cell-based therapy and particularly, mesenchymal stem cells (MSCs) therapy has obtained desired outcomes in decreasing the mortality rate of severe acute respiratory syndrome coronavirus 2 (SARS-COV-2), mainly owing to its immunoregulatory impact that prevents the overactivation of the immune system. Also, these cells with their multipotent nature, are capable of repairing the damaged tissue of the lung which leads to reducing the probability of acute respiratory distress syndrome (ARDS). Although this cell-based method is not quite cost-effective for developing countries, regarding its promising results in order to treat SARS-COV-2, more economical evaluation as well as clinical trials should be performed for improving this therapeutic approach. Here in this article, the functional mechanism of MSCs therapy for the treatment of COVID-19 and the clinical trials based on this method will be reviewed. Moreover, its economic efficiency will be discussed.