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The development of highly effective chitosan-based hemostatic materials that can be utilized for deep wound hemostasis remains a considerable challenge. In this study, a hemostatic antibacterial chitosan/N-hydroxyethyl acrylamide (NHEMAA)/Ti 3 C 2 T x (CSNT) composite cryogel was facilely prepared through the physical interactions between the three components and the spontaneous condensation of NHEMAA. Because of the formation of strong crosslinked network, the CSNT cryogel showed a developed pore structure (~ 99.07 %) and superfast water/blood-triggered shape recovery, enabling it to fill the wound after contacting the blood. Its capillary effect, amino groups, negative charges, and affinity with lipid collectively induced rapid hemostasis, which was confirmed by in vitro and in vivo analysis. In addition, CSNT cryogel showed excellent photothermal antibacterial activities, high biosafety, and in vivo wound healing ability. Furthermore, the presence of chitosan effectively prevented the oxidation of MXene, thus enabling the long-term storage of the MXene-reinforced cryogel. Thus, our hemostatic cryogel demonstrates promising potential for clinical application and commercialization, as it combines high resilience, rapid hemostasis, efficient sterilization, long-term storage, and easy mass production., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

Accidental bleeding is an unavoidable problem in daily life. To avoid the risk of excessive blood loss, it is urgent to design a functional material that can quickly stop bleeding. In this study, an efficient wound dressing for hemostasis was investigated. Based on the characteristics that Ca 2+ and fish skin collagen (FSC) could activate the coagulation mechanism, hemostatic cotton was prepared by solvent replacement method using CaCl 2 , FSC, soluble starch (SS), and polyvinyl alcohol (PVA) as raw materials. The cytotoxicity test showed the Ca 2+ PVA/FSC-SS hemostatic cottons had good biocompatibility. The activated partial thromboplastin time (APTT) of Ca 2+ PVA/FSC-SS(4) was 35.34 s, which was 22.07 s faster than that of PVA/FSC-SS, indicating Ca 2+ PVA/FSC-SS mediated the endogenous coagulation system. In vitro coagulation test, Ca 2+ PVA/FSC-SS(4) could stop bleeding rapidly within 39.60 ± 5.16 s, and the ability of wound healing was higher than commercial product (Celox). This study developed a rapid procoagulant and hemostatic material, which had a promising application in a variety of environments., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Chitin is a popular hemostatic material, but there are still many deficiencies in its ability to effectively stop bleeding, prevent infection, and fit wounds. Herein, AgNP@zeolite/chitin/bamboo (AgZ-CB) composite sponges with shape recovery are prepared to minimize blood loss, kill bacteria, and promote wound healing. Notably, the bamboo powder is used for the first time to remarkably enhance the softness of the composite sponge (volumetric expansion ratio >5). The fabricated AgZ-CB sponge exhibits an excellent killing effect (≈100% bactericidal rate) against both Escherichia coli and Staphylococcus aureus and activates internal and external coagulation pathways to accelerate hemostasis without causing thermal damage (≈5 °C temperature difference). Moreover, the AgZ-CB sponge shows less blood loss (26 mg) and a shorter time to hemostasis (42 s) than the commercial polyvinyl formal sponge (84 mg and 76 s) in the full-thickness liver injury model. The in vivo wound healing and biodegradation experiment indicate that AgZ-CB with excellent biocompatibility can close wounds efficiently. Overall, the AgZ-CB sponge has great potential in combating a series of obstacles in wound healing., (© 2023 Wiley-VCH GmbH.)

The hemorrhage in daily life was a great challenge for the life health. Before hospitalization and infection, stopping traumatic bleeding timely is an important measure to decrease the death threat. The high crystallinity and low porous structure of chitin (CH) make texture of sole CH sponge not soft enough, which limit its hemostatic properties. In this work, loose corn stalk (CS) was used to modify the structures and properties of sole CH sponge. The novel hemostatic composite sponge of CH/CS4 was prepared by cross-linking and freeze-drying process of chitin and corn stalk suspension. The composite sponge obtained best physical and hemostatic properties at the 1:1 volume ratio of chitin and corn stalk. Thanks to the porous structures, CH/CS4 possessed high water/blood absorption ability (34 ± 2 g/g and 32.7 ± 2 g/g), rapid hemostatic time (31 s) and low blood loss (0.31 g), allowing it to be delivered into the wound bleeding sites to reduce the wound bleeding by robust physical barrier and pressure effect. Furthermore, CH/CS4 displayed excellent hemostatic performance than sole CH and commercial polyvinyl fluoride sponge (PVF). Moreover, CH/CS4 displayed superior wound healing ability and cytocompatibility. Therefore, the CH/CS4 has high potential application in medical hemostatic field., Competing Interests: Declaration of competing interest The authors declare no competing financial interests and any non-financial competing interests., (Copyright © 2023. Published by Elsevier B.V.)

The development of shape-memory sponge dressings with functions, such as hemostasis, antibacterial activity, and wound healing, is of great significance in clinical applications. Herein, a novel AuNPs@corn stalk/chitin composite sponge (CCAu) was fabricated by crosslinking the chitin matrix with corn stalk-embedded gold nanoparticles (AuNPs). The addition of AuNPs@corn stalk gave the porous chitin sponge shape-recovery ability with improved softness, porosity, and water absorption. Correspondingly, the composite sponge showed better hemostatic effects than commercial PVF sponges. The photothermal effect of AuNPs endowed the composite sponge with excellent antibacterial activity. In addition, the wound treated with composite sponge containing antioxidant AuNPs exhibited a significantly faster wound healing rate (reaching 41.6 % on day 3) than the CH (33.2 %) and control (12.6 %) group through promoting cell migration, angiogenesis and collagen deposition. Therefore, the multifunctional composite sponge with great biocompatibility in this work provides a potential strategy for wound healing., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

This study shows the effective use of MXene-based nanomaterials to improve the performance of biocomposite sponges in wound healing. In this way, diverse chitin/MXene composite sponges are fabricated by incorporating MXene-based nanomaterials with various morphology (accordion-shaped, intercalated, single-layer, gold nanoparticles (AuNPs)-loaded single-layer) into the network of chitin sponge (CH), which can prevent massive blood losses and promote the healing process of bacterial-infected wounds. With the addition of MXene-based nanomaterials, the hemostatic efficacy of CH is enhanced due to the improved hemophilicity and accelerated blood coagulation kinetics. Furthermore, the composite sponges show a predominant antibacterial activity through the synergy between the capture and the photothermal effects. Importantly, the addition of AuNPs to composite sponges further improves hemostatic performance and promotes normal skin cell migration to heal the infected wound, achieving wound closure rates of 84% on day 9. These initial studies expand the applications of MXene-based nanomaterials in biomedical fields., (© 2022 Wiley-VCH GmbH.)

Hydrogels are functional materials that are similar to human skin and have received much attention in recent years for biomedical applications. However, the preparation of nontoxic, highly adhesive, and antimicrobial hydrogels in an efficient way remains a great challenge. Inspired by adhesive mussel foot proteins (mfps) which consist of abundant catecholic amino acids and lysine (Lys) residues, gallic acid-modified ε-poly-L-lysine (EPL/GA) was synthesized, and an active functional monomer (AA-EPL/GA) was then created through a reaction with acrylic acid (AA). The polymerization of AA-EPL/GA occurred rapidly (30-160 s) under blue light (λ = 405 nm) irradiation to produce a biomimetic PAA-EPL/GA hydrogel under mild conditions. The biomimetic pyrogallol-Lys distribution endowed the PAA-EPL/GA hydrogels with superior adhesion in humid environments (with an adhesive strength of 50.02 kPa toward wet porcine skin) and tunable mechanical and self-healing properties. Additionally, the PAA-EPL/GA hydrogels exhibited outstanding antibacterial ability due to the inherent characteristics of GA and EPL. In a mouse model, PAA-EPL/GA adhered firmly around the wound tissues. Photographs of the wound and the histological results demonstrated the ability of the hydrogel to promote wound healing, control wound infection, and suppress scar formation. Moreover, the hydrogel had a good hemostatic effect on liver bleeding. Our results highlighted the promising application potential of GA-based hydrogels, which were easily, harmlessly, and efficiently fabricated by blue light irradiation., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Wound bleeding and infection are two of the major threats to patients' lives, but developing safe materials with high hemostasis efficiency and antibacterial activity remains a major challenge. Silver nanoparticles (AgNPs) are suitable as antibacterial agents in the hemostatic process, but the application is hampered because of easy accumulation of toxicity. Herein, thiol-modified chitosan (TMC) was prepared by modifying with mercaptosuccinic acid and then was used to immobilize AgNPs to obtain composite sponges (TMC/AgNPs) for stemming the bleeding and preventing infection. TMC/AgNPs sponges had complex interlaced tubular porous structure with high porosity (99.42%), indicating high absorption. TMC had high immobilization efficiency for AgNPs-the release rate of AgNPs was 14.35% after 14 days-but the TMC/AgNPs sponge still had excellent antibacterial activity against Staphylococcus aureus , Escherichia coli , and Pseudomonas aeruginosa . In vitro and in vivo experiments confirm that the TMC/AgNPs sponge had fast and efficient hemostatic performance in comparison with the PVF sponge, and its possible mechanism was the synergistic effect of high blood absorption capacity and the interaction between amino, sulfydryl, and blood cells. Furthermore, the TMC/AgNPs sponge can promote wound healing by preventing wound infection, while the PVF sponge cannot. More importantly, the sponges had good safety due to the immobilization of TMC for AgNPs.

Bacterial infection and uncontrolled bleeding are the major challenges facing the wound treatment. In order to solve these problems, we have devised a green nanocomposite hydrogel by introducing the aminated silver nanoparticles (Ag-NH 2 NPs) and gelatin (G) to carboxylated cellulose nanofibers (CNF). Interpenetrating polymeric network (IPN) was formed by interaction of multicomponent, leading to the non-covalent (dynamic ionic bridges) crosslinked hydrogel CNF/G/Ag. The produced hydrogel dressing with 0.5 mg/mL Ag-NH 2 NPs (CNF/G/Ag 0.5 ) demonstrated stronger mechanical, self-recovery, antibacterial properties, satisfactory hemostatic performance, and appropriate balance of fluids on the wound bed (2093.9 g/m 2 per day). More importantly, the wound healing model evaluation in vitro and in vivo of CNF/G/Ag 0.5 showed an outstanding biocompatibility (∼100% infected cell viability) and wound healing efficacy (∼90% healed and 83.3% survival after 14 days). Our study paved a highly promising approach to improve the performance of cellulose-based hydrogel dressing and would also be useful for developing ideal skin wound dressings by other green materials., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

We evaluated the effectiveness of a novel hemostatic powder called Tranexamic Acid-loaded Porous Starch (TAPS) developed recently on blood clotting activity and hemostasis. The effectiveness of TAPS was evaluated by comparing hemostatic properties with those of Quick-acting Styptic Powder (QSP) and Compound Microporous Polysaccharide Haemostatic powder (CMPHP). The blood clotting activities of human blood were analyzed by thromboela-stogram (TEG) assays in vitro. The hemostatic effectiveness in vivo was evaluated using a rat model with hepatic traumatic hemorrhage. The blood loss and standardized bleeding score, which reflects the degree of bleeding after treatment with styptic powder, were used to evaluate hemostatic efficacy. In vitro, the values of TEG parameters in TAPS group were significantly different, compared with untreated controls or CMPHP group (p < 0.05). In vivo, the application of QSP, CMPHP and TAPS led to significantly decreased post-treatment blood loss than in the control group (p < 0.01). The scores of the groups treated with QSP, CMPHP and TAPS (0, 0.2±0.422, 0.3±0.483, respectively) were significant lower than with gauze control (1.6±0.516) which success hemostatic was achieved at 5 minutes (p < 0.01). Hemostasis was achieved successfully within approximately 4 minutes after the application of TAPS. TAPS could help blood to form an artificial scab on a wound and to seal injuries for hemostasis to reduce blood loss in rats with hepatic trauma and hemorrhage. It was safe to use with no impact on blood clotting function or other apparent side effects.