Chitosan Sponge Research Articles

Highly resilient, biocompatible, and antibacterial carbon nanotube/hydroxybutyl chitosan sponge dressing for rapid and effective hemostasis.

Uncontrolled hemorrhage is the leading cause of trauma death. The development of safe and efficient hemostatic agents that can rapidly and effectively control bleeding is of great significance to rescue the injured. However, the mechanical, absorptive, and antibacterial properties of conventional two-dimensional hemostatic agents are not satisfactory. Herein, a series of effective three-dimensional hemostatic dressings (JWCNT/HBC sponges) are developed by chemical modification of joint-welded carbon nanotube (JWCNT) sponges with hydroxybutyl chitosan (HBC) for hemorrhage hemostasis. The JWCNT/HBC sponges exhibit high elasticity, porous structure, and suitable blood-absorption and blood-maintaining performance. Moreover, the introduction of HBC endows the JWCNT/HBC sponges with favorable blood compatibility and good antibacterial activity. The sponge treated with 0.5% HBC (JWCNT/0.5%HBC sponge) displays better antiseptic capability, faster blood clotting ability in vitro and shorter hemostasis time in vivo than the commercial gelatin sponge. The JWCNT/HBC sponges combine the advantages of JWCNT sponges and HBC in the adhesion and activation of platelets and red blood cells, thus becoming a good medical material for trauma hemostasis.

Management of recurrent aphthous ulcers exploiting polymer-based Muco-adhesive sponges: in-vitro and in-vivo evaluation

Recurrent aphthous ulcer (RAU) is a well-known painful, inflammatory disease with uncertain etiology for which local symptomatic therapy is only available. The aim of this study was to formulate and characterize muco-adhesive sponges containing a mixture of tenoxicam and miconazole nitrate to manage pain, inflammation and avoid candida infection that may accompany RAU due to poor oral hygiene. Two polymers at different concentrations were used to prepare sponges applying simple freeze-drying. Medicated chitosan (2%) sponges (mC2) showed acceptable physical appearance, surface pH (6.3 ± 0.042), porosity (25.7% ± 1.8), swelling index (5.7 ± 0.11), in-vivo and ex-vivo muco-adhesion time (115 min.±0.813 and 155 min.±1.537, respectively), ex-vivo muco-adhesion force (0.09 N ± 0.002) and scanning electron microscope (SEM) images. For concurrent clear-cut determination of tenoxicam and miconazole nitrate from mC2, a new UPLC method was developed and validated. mC2 sponges exhibited superior in-vitro drug release profiles where ∼100% of tenoxicam released within 5 min for fast pain relief with a more prolonged miconazole nitrate release. Furthermore, in-vivo animal study revealed that mC2 caused a significant decrease in the acetic acid-induced ulcer size in rats after 6 days of treatment (p < .0001) compared to negative and positive controls. Additionally, histopathological examination showed faster healing with complete restoration of the normal oral histology in rats. The present study concludes that chitosan sponge loaded with a combination of tenoxicam and miconazole nitrate could improve healing of RAU cases.

One-step fabrication of chitosan sponge and its potential for rapid hemostasis in deep trauma

In this paper, a facile and efficient preparation strategy for a porous and hydrophilic chitosan sponge is demonstrated, combining a surfactant and a pore-foaming agent. The resulting chitosan sponge possesses an interconnected pore structure and soft texture, exhibits fast water absorption rate and capacity, and the compressed sponge can achieve full shape recovery 5 s after absorbing water. Moreover, our process removes the residual acid commonly found in chitosan sponges prepared by the acid method. In addition, the results demonstrate the useful characteristics of our chitosan sponge, in terms of its contribution to improved blood coagulation, together with its compression strength and biocompatibility. It also demonstrates effective antibacterial properties in relation to both Escherichia coli and Staphylococcus aureus. Further testing via animal experimentation reveals that rapid hemostasis can be achieved within 50 s using our chitosan sponge.

In vitro biological response of human osteoblasts in 3D chitosan sponges with controlled degree of deacetylation and molecular weight

We have studied the effect of chitosan sponges, produced from chitosan batches with distinct degree of deacetylation (DDA) and molecular weight (Mw), on the adhesion, growth and differentiation of primary human osteoblasts with an aim to offer a suitable tool for guided bone regeneration. All the chitosan sponges revealed similar microstructure, irrespective of the DDA (58, 73, 82, 88, and 91 %) and Mw (749, 547, 263, 215, and 170 kDa, respectively). Cell spreading was higher on sponges having a higher DDA. Higher DDA induced a more pronounced increase in alkaline phosphatase activity, osteopontin (OPN), vascular endothelial growth factor-A (VEGF), interleukin-6 (IL-6), and reduction in monocyte chemoattractant protein-1 (MCP-1), sclerostin (SOST) and dickkopf related protein-1 as compared to lower DDA. Lower DDA induced the increased secretion of osteoprotegerin and SOST as compared to higher DDA. The combination of higher DDA and Mw induced an increased secretion of VEGF and IL-6, however reduced the secretion of OPN as compared to chitosan with similar DDA but with lower Mw. In summary, the variations in cellular responses to the different chitosan sponges indicate a potential for individual tailoring of desired responses in guided bone regeneration.

Multifunctional Tissue-Adhesive Cryogel Wound Dressing for Rapid Nonpressing Surface Hemorrhage and Wound Repair.

Cryogels with tissue adhesion have great potential as wound dressings for rapid hemostasis for uncontrollable nonpressing surface hemorrhage and wound healing, but their use has not been reported previously. Herein, we designed a series of antibacterial and antioxidant tissue-adhesive cryogels based on quaternized chitosan (QCS) and polydopamine (PDA). These cryogels had good blood cell and platelet adhesion, enrichment, and activation properties for rapid nonpressing surface hemostasis and wound healing. The cryogels exhibited outstanding mechanical strength and easy removability, antioxidant activity, and NIR photothermal-enhanced antibacterial performance. The cryogels showed much better hemostasis than gauze and gelatin sponge in a standardized strip rat liver injury model, a standardized circular rabbit liver section model, and a pig skin laceration model. Furthermore, the excellent hemostatic performance of the QCS/PDA2.0 cryogel (containing 20 mg/mL QCS and 2.0 mg/mL PDA) for coagulopathic hemorrhages was confirmed in a standardized coagulation disorder rabbit circular liver section model. In addition, the QCS/PDA2.0 cryogel promoted rapid hemostasis in a deep noncompressible wound and a much better wound healing effect than a chitosan sponge and Tegaderm film in a full-thickness skin defect model. Overall, these multifunctional tissue-adhesive cryogels with excellent hemostatic performance and enhanced wound healing properties are suitable candidates for tissue-adhesive hemostat and wound healing dressings.

Injectable dry cryogels with excellent blood-sucking expansion and blood clotting to cease hemorrhage for lethal deep-wounds, coagulopathy and tissue regeneration

Designing expandable dry cryogels with biodegradability, rapid blood-sucking expansion and hemostasis for lethal non-compressible hemorrhage and coagulopathy hemorrhage still remains a challenge. Herein, we designed a series of antioxidant, photo-thermal and antibacterial expandable dry cryogels based on polydopamine crosslinked chitosan. The cryogels presented excellent antioxidant activity, outstanding NIR-enhanced antibacterial activity, rapid thrombin release, better blood clotting capacity, and higher blood cells/platelets adhesion and activation than Combat Gauze and gelatin sponge. Besides, all the cryogels showed less blood losses than Combat Gauze and gelatin sponge in mouse liver trauma model, and CS20/PDA4.5 (prepared by 20 mg chitosan and 4.5 mg dopamine) showed the least blood loss. Moreover, CS20/PDA4.5 presented much better hemostatic performance than Combat Gauze and gelatin sponge in rabbit liver non-compressible hemorrhage model with and without administrating anticoagulant. Especially, CS20/PDA4.5 presented excellent hemostatic performance in lethal non-compressible swine subclavian artery and vein transection model. Furthermore, the cryogel showed better wound healing performance than chitosan sponge and Tegaderm™ film. This facile approach opens up new avenue to develop expandable dry cryogels hemostats for lethal non-compressible hemorrhage, coagulopathy hemorrhage and tissue engineering.

Utilization of biodegradable chitosan-derived sponges as oil retainers.

An innovative approach of chitosan-derived biodegradable sponges with high sorption capacity, excellent recyclability, and inherent oleophilic properties have been developed for the first time to remove the crude oil polluting the environment. Chitosan-nitrogen mustard ionic carbonate-β-cyclodextrin (CH-NMIC-CD), chitosan-nitrogen mustard ionic carbonate (CH-NMIC), and chitosan (CH) sponges with macropores were prepared using tripolylphosphate (TPP) by adopting subsequent lyophilization. Detailed characterization such as FTIR, TGA, XRD, and SEM has been done to confirm the formation, stability, crystalline nature, and morphology of the prepared sponges. The FTIR spectra confirmed the successful incorporation of NMIC in CH-NMIC-CD and CH-NMIC and the presence of β-CD in the (CH-NMIC-CD). It was found from the TGA results that the presence of β-CD makes the sponge CH-NMIC-CD stable. SEM analysis showed the morphology of the sponges found to be highly porous with interconnected macropores. The oil absorption capacity was 12.30 goil/gns higher for the sponge CH-NMIC-CD followed by CH-NMIC and CH. The sponges showed reusability excellently even after consecutive sorption-desorption separation cycles for five times. Moreover, the sponges were completely biodegraded within 25days. The finding holds a promising future to use CH-NMIC-CD sponges in pollutant entrapment particularly in the removal of crude oil and allied area.

Influence of the Introduced Chitin Nanofibrils on Biomedical Properties of Chitosan-Based Materials.

Hemorrhage occurring during and after surgery still remains one of the biggest problems in medicine. Although a large number of hemostatic products have been created, there is no universal preparation; thus, the development of new materials is an urgent task. The aim of this research is to increase hemostatic properties of chitosan by introducing chitin nanofibrils (ChNF). The blood absorbance by ChNF-containing chitosan sponges and time-until-arrest of bleeding were studied. Non-woven materials containing 0.5% of ChNF and materials without chitin were obtained. The studies of ζ-potential showed that the material containing 0.5% ChNF had relatively a high positive charge, but efficiencies of both materials for hemorrhage arrest were comparable to those of commercial hemostatic products (Surgicel and TachoComb). To investigate the interaction between the materials and living organism, histological studies and optical microscopy studies were conducted after implantation of fibers. Despite bioinertness of fibers, implantation of non-woven materials led to formation of significant granulomas.

Effective decontamination of 99TcO4−/ReO4− from Hanford low-activity waste by functionalized graphene oxide–chitosan sponges

Treatment and recycling of radioactive waste are major challenges for the nuclear energy sector. Pertechnetate anions, 99TcO4−, occur in nuclear waste and are formed mainly during nuclear fission. 99TcO4− is a very hazardous contaminant due to its long half-life and high solubility and mobility in water. The effective capture of 99Tc contamination at legacy nuclear sites remains a serious and unsolved environmental issue. In this work, 99TcO4−/ReO4− was adsorbed by compressible graphene–chitosan sponges with grafted tertiary amine groups. Moreover, the hydrophobic branched chains strongly reduced the interference of competitive anions during adsorption. Results show that 99TcO4−/ReO4− can be effectively removed even under highly acidic conditions and in the presence of competing anions. More than 98% of 99TcO4−/ReO4− was removed using simulated nuclear wastes.

A Sponge-Like Double-Layer Wound Dressing with Chitosan and Decellularized Bovine Amniotic Membrane for Promoting Diabetic Wound Healing.

The diabetic wounds do not heal easily in part because they are susceptible to infection due to environmental influences. Wound dressing is crucial to wound healing, as it can basically protect the wound from external damages and provide a suitable microenvironment for tissue regeneration. In this study, a double-layer membrane that consists of chitosan sponge and decellularized bovine amniotic membrane (dBAM) has been developed by freeze-casting method. The results showed that the porous structure of the sponge layer improved the performances of blood coagulation and swelling. The dense dBAM can optimize the mechanical property of wound dressing. In vitro studies revealed that the bilayer membrane had favorable biocompatible, especially for human foreskin fibroblast cells (HFF-1) cell adhesion and proliferation. Moreover, the full-thickness skin defects of diabetic model mice that treated with bilayer membrane showed over 80% closure in 8 days. Our findings imply that the double-layer dressing has great potentials to be used in diabetic patients.

Antibacterial, mechanical and physical properties of collagen - chitosan sponges from aquatic source

Collagen and chitosan, used for the preparation of sponges, were isolated from the residues of aquatic origin, and co-adjuvant material alginate was added. All sponges are light-colored, but those formulated with chitosan have a yellow hue. The chemical interaction between the components was confirmed by Fourier-transform infrared spectroscopy. The porosity of the sponges is in the range from 88 to 95%. The sponges based on collagen/chitosan/alginate exhibited the highest capacity for absorption in water at 25 °C, with values of up to 2838%. Collagen-chitosan sponges have less rigidity and mechanical strength than collagen-alginate sponges. Collagen-alginate sponges contained the highest maximum stress and Young's modulus, with values of 0.5463 MPa and 0.0086 MPa, respectively. Collagen sponges with chitosan have a greater elongation at break (6.1566%). The sponges with the highest antimicrobial activity were collagen-chitosan mixtures, with inhibition zones of up to 46.62% against Staphylococcus aureus. We anticipate that the sponges based on fish collagen and shrimp chitosan can serve as an alternative of biomaterial for the healing of cutaneous wounds due to their mechanical and antibacterial properties.

Removal of fluoride from fertilizer industry effluent using carbon nanotubes stabilized in chitosan sponge

Adsorption of fluoride from fertilizer industry effluent using carbon nanotubes stabilized in chitosan sponge as adsorbent was evaluated. The effluent was produced in the washing of acid gases during the reaction in fertilizer production and all assays were performed using this hazardous material. Adsorbent characterization and ions interactions were elucidated from differential scanning calorimetry, thermal gravimetric analyses, X–ray diffraction, scanning electron microscopy dispersive energy X–ray spectroscopy, atomic force microscopy and X-ray photoelectron spectroscopy. The effluent presented pH 3 and its value not changed in the adsorption assays, maintaining the conditions of the process. The kinetics assays of fluoride from industry effluent were performed in different stirring rates from 100 to 300 rpm. It was observed that adsorption was initially fast reaching the equilibrium at 300 rpm in 20 min. The adsorption capacity was around 975.4 mg g−1, showing the potential of the hybrid material to remove fluoride from a real matrix. The high adsorption capacity was attributed to the chitosan functional groups and the high interaction area promoted by sponge form and the carbon nanotube. Reuse and regeneration of the CNT-CS were investigated and 5 cycles were obtained. The adsorption capacity kept similar values in all cycles.

HGF Gene Delivering Alginate/Galactosylated Chitosan Sponge Scaffold for Three-Dimensional Coculture of Hepatocytes/3T3 Cells.

Gene delivery from tissue engineering scaffold is a novel strategy in regulating long-term growth and function of cells in vitro culture. In this study, a hepatocyte growth factor plasmid/polyetherimide (pHGF/PEI) polyplex delivering alginate (AL)/galactosylated chitosan (GC) (pHGF/PEI-AL/GC) sponge scaffold was prepared for the in vitro coculture of hepatocytes/3T3 cells. The pHGF/PEI polyplex released for 6 days in the sponge scaffold with weight ratio of AL/GC being 3:1 and fixed amount of pHGF being 40 μg (24-well scaffold). In addition, the 3T3 cells culturing in the pHGF/PEI-AL/GC sponge scaffold could be continually transfected and expressed the exogenous HGF for 6 days. Furthermore, the albumin secretion and urea synthesis of hepatocytes were significantly enhanced when cocultured with 3T3 cells in the pHGF/PEI-AL/GC sponge scaffold compared with that in the AL/GC sponge without pHGF. In summary, the preparation of AL/GC sponge scaffold delivering pHGF/PEI polyplex is a critical significance for maintaining the long-term survival and function of primary hepatocytes in vitro.

Разработка костно-пластического материала, импрегнированного плазмидой с геном костного морфогенетического белка-2

The biological properties of a new gene-activated osteoplastic material based on chitosan sponges impregnated with plasmids with the gene for the bone morphogenetic protein-2 (BMP2) have been studied. The optimal conditions for transfection of multipotent mesenchymal stromal cells with TurboFect reagent were selected. The in vitro osteoinducing effect of the developed material associated with an increase in the expression of osteogenic markers in mesenchymal stromal cells was shown. The designed gene-activated material can be used to repair bone defects. gene-activated material, plasmids, BMP-2, gene therapy, bone regeneration The work was supported by the Russian Science Foundation (Grant no. 16-15-00298).

The use of chitosan-based biomaterials for the treatment of hard-healing wounds

Wound healing is a complex process that engages skin cells, the blood, the immune system and a number of circulating substances in the body. Infections, contamination of the wound or a vast area of damage complicate and delay the natural process of skin regeneration. The incidence of hard-to-heal wounds is an increasingly common problem, because they can significantly impair the quality of life of the patient. For this reason, it is extremely important to look for factors (drugs, dressings or other substances) that could accelerate and relieve wound healing. Among many compounds in the area of medical engineering interest, attention should be paid to natural polysaccharides, e.g. chitosan and alginate. This article is devoted to biomaterials that play an important role in the treatment of chronic wounds. These include the following: hydrogels, non-wovens, membranes and chitosan sponges as well as chitosan-alginate composites or chitosan composites combined with zinc oxide and nanosilver. The material, which has chitosan as a base, works on all stages of the healing process. Many in vitro, in vivo and clinical studies that provide the basis for using chitosan materials as a substitute for conventional bandages and dressings have been carried out. At the stage of hemostasis, it accelerates platelet aggregation and the formation of a fibrin clot. In the inflamed stage, they cause the proliferation of neutrophils and macrophages that cleanse the wound, releasing cytokines at the wound site. Studies have shown that chitosan mimics the native extracellular matrix, providing the optimal microenvironment for the wound.

Characterization of dexamethasone loaded collagen-chitosan sponge and in vitro release study

The aim of the present work is the development of porous mucoadhesive bio-sponge as a vehicle for release of dexamethasone for the treatment of oral mucositis. The influence of mixing collagen with chitosan on crystallinity structure and thermal behavior of both polymers were investigated. The polymer blends and dexamethasone-loaded polymers were characterized by FT-IR, SEM scanning, and swelling ability. The release study of the drug from chitosan, collagen, and collagen-chitosan (1:1) sponges was carried out in vitro. X-Ray diffraction of the collagen-chitosan film showed a semi-crystalline structure, that has a great influence on drug release. DSC curve showed one endothermal peak for neat and hybrid polymer sponges, confirming there was no denaturation of collagen fiber, and there was no phase separation between polymers. FT-IR results showed the forming of electrostatic and H-bonding between collagen and chitosan and the forming of H-bonding between dexamethasone and studied polymers. SEM for sponges showed that adding collagen to chitosan increased pores size, dexamethasone was clearly shown immobilized on the surface of polymer films. Drug release from the hybrid sponge was faster than the chitosan sponge, which ended in 16 h, and was slower than the collagen sponge which ended in 5 h. The formulation based on collagen-chitosan (1:1) blend was able to control drug release within 10 h.

Evaluation of Chitosan-based Dressings in a Swine Model of Artery-Injury-Related Shock

Uncontrolled haemorrhage shock is the highest treatment priority for military trauma surgeons. Injuries to the torso area remain the greatest treatment challenge, since external dressings and compression cannot be used here. Bleeding control strategies may thus offer more effective haemostatic management in these cases. Chitosan, a linear polysaccharide derived from chitin, has been considered as an ideal material for bleeding arrest. This study evaluated the potential of chitosan-based dressings relative to commercial gauze to minimise femoral artery haemorrhage in a swine model. Stable haemostasis was achieved in animals treated with chitosan fibre (CF) or chitosan sponge (CS), resulting in stabilisation of mean arterial pressure and a substantially higher survival rate (100% vs. 0% for gauze). Pigs receiving treatment with CF or CS dressings achieved haemostasis within 3.25 ± 1.26 or 2.67 ± 0.58 min, respectively, significantly more rapidly than with commercial gauze (>100 min). Moreover, the survival of animals treated with chitosan-based dressings was dramatically prolonged (>180 min) relative to controls (60.92 ± 0.69 min). In summary, chitosan-based dressings may be suitable first-line treatments for uncontrolled haemorrhage on the battlefield, and require further investigation into their use as alternatives to traditional dressings in prehospital emergency care.

Transforming Growth Factor-β3/Chitosan Sponge (TGF-β3/CS) Facilitates Osteogenic Differentiation of Human Periodontal Ligament Stem Cells.

Periodontal disease is the main reason for tooth loss in adults. Tissue engineering and regenerative medicine are advanced technologies used to manage soft and hard tissue defects caused by periodontal disease. We developed a transforming growth factor-β3/chitosan sponge (TGF-β3/CS) to repair periodontal soft and hard tissue defects. We investigated the proliferation and osteogenic differentiation behaviors of primary human periodontal ligament stem cells (hPDLSCs) to determine the bioactivity and potential application of TGF-β3 in periodontal disease. We employed calcein-AM/propidium iodide (PI) double labeling or cell membranes (CM)-Dil labeling coupled with fluorescence microscopy to trace the survival and function of cells after implantation in vitro and in vivo. The mineralization of osteogenically differentiated hPDLSCs was confirmed by measuring alkaline phosphatase (ALP) activity and calcium content. The levels of COL I, ALP, TGF-βRI, TGF-βRII, and Pp38/t-p38 were assessed by western blotting to explore the mechanism of bone repair prompted by TGF-β3. When hPDLSCs were implanted with various concentrations of TGF-β3/CS (62.5–500 ng/mL), ALP activity was the highest in the TGF-β3 (250 ng/mL) group after 7 d (p < 0.05 vs. control). The calcium content in each group was increased significantly after 21 and 28 d (p < 0.001 vs. control). The optimal result was achieved by the TGF-β3 (500 ng/mL) group. These results showed that TGF-β3/CS promotes osteogenic differentiation of hPDLSCs, which may involve the p38 mitogen-activated protein kinase (MAPK) signaling pathway. TGF-β3/CS has the potential for application in the repair of incomplete alveolar bone defects.

Preparation of Chitosan, Sodium Alginate, Gelatin and Collagen Biodegradable Sponge Composites and their Application in Wound Healing and Curcumin Delivery

This research aimed to produce three chitosan-based biodegradable sponge composites from collagen, gelatin, and sodium alginate and through addition of curcumin to investigate their biological effects on wound healing. To this end, the Chitosan-Collagen-Curcumin (Chs, Col, Cur), Chitosan-Gelatin-Curcumin (Chs, Gel, Cur), and Chitosan-Alginate-Curcumin (Chs, Alg, Cur) sponge composites were prepared and subject to FT-IR, SEM, TGA, water absorption, biodegradability, wound healing and anti-bacterial analyses. Based on the results, the highest and lowest water absorptions were associated with Chitosan-Alginate-Curcumin and Chitosan-Collagen-Curcumin composites, respectively. Moreover, according to the SEM images, the highest porosity and the largest cavity size were associated with the Chitosan-Alginate-Curcumin composite. The biodegradability analysis results revealed that Chitosan-Alginate-Curcumin was completely destroyed in 4 days, while the Chitosan-Collagen-Curcumin composite showed the lowest level of destruction. Moreover, the highest amount of curcumin was released by the Chitosan-Gelatin-Curcumin composite which happened during the first hour. Finally, the highest wound healing effect was achieved within a 10-day period using the Chitosan-Gelatin-Curcumin composite, completely healing the wound on the mouse skin. On the other hand, the lowest effect was associated with the Chitosan-Alginate-Curcumin composite. The antibacterial tests suggested that all composites exhibited anti-bacterial capabilities, the highest level of which was associated with the Chitosan-Gelatin-Curcumin composite. Moreover, based on the histological tests, the fastest tissue repair process with the highest quality was achieved using the Chitosan-Gelatin-Curcumin sponge composite.

Preparation of a novel asymmetric wettable chitosan-based sponge and its role in promoting chronic wound healing

Cutaneous chronic wounds are characterized by an impaired wound healing which may lead to infection. To surmount this problem, a novel quaternary ammonium chitosan nanoparticles (TMC NPs)/chitosan (CS)composite sponge with asymmetric wettability surfaces was successfully prepared. The optimum concentrations of TMC NPs and CS were 0.2 mg/mL and 2.0%, respectively. The incorporated TMC NPs could improve the antibacterial activity of the CS sponge. Asymmetric modification enables the CS sponge to have hydrophobic outer surface and hydrophilic inner surface. The hydrophobic surface of the sponge shows waterproof and anti-adhesion contaminant properties, whereas the hydrophilic surface preserves water-absorbing capability and efficiently inhibits the growth of bacteria. More importantly, in vivo chronic wound healing model evaluation reveals that TMC NPs/CS composite sponge promotes the wound healing and accelerates re-epithelialization and angiogenesis. And in vivo anti-infection test shows the TMC NPs/CS composite sponge could effectively prevent wound infection. These findings demonstrate that TMC NPs/CS composite sponge is a promising dressing material for chronic wounds.