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Hydrogels are three-dimensional crosslinked functional materials with water-absorbing and swelling properties. Many hydrogels can store a variety of small functional molecules to structurally and functionally mimic the natural extracellular matrix; hence, they have been extensively studied for biomedical applications. Polyamidoamine (PAMAM) dendrimers have an ethylenediamine core and a large number of peripheral amino groups, which can be used to engineer various polymer hydrogels. In this review, an update on the progress of using PAMAM dendrimers for multifunctional hydrogel design was given. The synthesis of these hydrogels, which includes click chemistry reactions, aza-Michael addition, Schiff base reactions, amidation reactions, enzymatic reactions, and radical polymerization, together with research progress in terms of their application in the fields of drug delivery, tissue engineering, drug-free tumor therapy, and other related fields, was discussed in detail. Furthermore, the biomedical applications of PAMAM-engineered nano-hydrogels, which combine the advantages of dendrimers, hydrogels, and nanoparticles, were also summarized. This review will help researchers to design and develop more functional hydrogel materials based on PAMAM dendrimers. [ABSTRACT FROM AUTHOR]

In recent years, the incidence of chronic pancreatitis has increased significantly. Pancreatic calculi obstruct the pancreatic duct and induce abdominal pain in the patients. Pancreatic duct stenting is the major treatment option for chronic pancreatitis with calculi. In this study, a new kind of drug-eluting stent, a pancreatic stent coated by methacrylated gelatin (GelMA) hydrogel loaded with citric acid (CA), was designed for the interventional treatment of pancreatic duct calculi. The CA loading capacity reached up to 0.7 g CA/g hydrogel-coated stent. The GelMA hydrogel coating has higher mechanical strength and lower swelling performance after loading with CA. The in vitro experiments of stents exhibited good performance in CA sustained release and the calculi can be dissolved in almost 3 days. The stents also showed good blood compatibility and cell compatibility. This research has important clinical value in the treatment of chronic pancreatitis with pancreatic calculi. [ABSTRACT FROM AUTHOR]

Hemostatic powder, which can absorb large amounts of water and tends to produce repeated hydration with tissue, has been clinically proven as an ideal engineering material for treating wounds and tissues. We herein designed a polypeptide-based hemostatic powder. A water-soluble polypeptide, γ-polyglutamic acid (γ-PGA), was mixed with the polyethyleneimine (PEI), N-hydroxysuccinimide, and 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide. The solution of these polymers was lyophilized to harvest the γ-PGA/PEI powder (PP hemostatic powder). When deposited on a bleeding wound, the PP hemostatic powder can quickly absorb a large amount of blood and interstitial fluid, concentrate coagulation factors, coagulate blood cells, and eventually form a stable mechanical hydrogel. The wound bleeding time of the PP hemostatic powder group was 1.8 ± 0.4 min, significantly lower than that of the commercial chitosan hemostatic powder group (2.8 ± 0.4 min). The PP hemostatic powder was endowed with antioxidant capacity by introducing protocatechuic aldehyde, which can effectively inhibit inflammation and promote wound healing. Therefore, via preparation through a facile lyophilization method, the PP hemostatic powder is expected to find a wide application prospect as a qualified hemostatic powder. [ABSTRACT FROM AUTHOR]

In recent years, multifunctional hydrogel nanoplatforms for the synergistic treatment of tumors have received a great deal of attention. Here, we prepared an iron/zirconium/polydopamine/carboxymethyl chitosan hydrogel with Fenton and photothermal effects, promising for future use in the field of synergistic therapy and prevention of tumor recurrence. The iron (Fe)–zirconium (Zr)@ polydopamine (PDA) nanoparticles were synthesized by a simple one-pot hydrothermal method using iron (III) chloride hexahydrate (FeCl3•6H2O), zirconium tetrachloride (ZrCl4), and dopamine, followed by activation of the carboxyl group of carboxymethyl chitosan (CMCS) using 1-(3-Dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC)/N(4)-hydroxycytidine (NHS). Finally, the Fe–Zr@PDA nanoparticles and the activated CMCS were mixed to form a hydrogel. On the one side, Fe ions can use hydrogen peroxide (H2O2) which is rich in the tumor microenvironment (TME) to produce toxic hydroxyl radicals (•OH) and kill tumor cells, and Zr can also enhance the Fenton effect; on the other side, the excellent photothermal conversion efficiency of the incorporated PDA is used to kill tumor cells under the irradiation of near-infrared light. The ability of Fe–Zr@PDA@CMCS hydrogel to produce •OH and the ability of photothermal conversion were verified in vitro, and swelling and degradation experiments confirmed the effective release and good degradation of this hydrogel in an acidic environment. The multifunctional hydrogel is biologically safe at both cellular and animal levels. Therefore, this hydrogel has a wide range of applications in the synergistic treatment of tumors and the prevention of recurrence. [ABSTRACT FROM AUTHOR]

The design of new hemostatic materials to mitigate uncontrolled bleeding in emergencies is challenging. Chitosan-based hemostatic hydrogels have frequently been used for hemostasis due to their unique biocompatibility, tunable mechanical properties, injectability, and ease of handling. Moreover, chitosan (CS) absorbs red blood cells and activates platelets to promote hemostasis. Benefiting from these desired properties, the hemostatic application of CS hydrogels is attracting ever-increasing research attention. This paper reviews the recent research progress of CS-based hemostatic hydrogels and their advantageous characteristics compared to traditional hemostatic materials. The effects of the hemostatic mechanism, effects of deacetylation degree, relative molecular mass, and chemical modification on the hemostatic performance of CS hydrogels are summarized. Meanwhile, some typical applications of CS hydrogels are introduced to provide references for the preparation of efficient hemostatic hydrogels. Finally, the future perspectives of CS-based hemostatic hydrogels are presented. [ABSTRACT FROM AUTHOR]

Postoperative adhesion is a common post-surgery complication formed between the surface of the body cavity, ranging from a layer of connective tissue to a fibrous bridge containing blood vessels and nerve tissue. Despite achieving a lot of progress, the mechanisms of adhesion formation still need to be further studied. In addition, few current treatments are consistently effective in the prevention of postoperative adhesion. Hydrogel is a kind of water-expanding crosslinked hydrophilic polymer network generated by a simple reaction of one or more monomers. Due to the porous structure, hydrogels can load different drugs and control the drug release kinetics. Evidence from existing studies has confirmed the feasibility and superiority of using hydrogels to counter postoperative adhesions, primarily due to their outstanding antifouling ability. In this review, the current research status of hydrogels as anti-adhesion barriers is summarized, the character of hydrogels in the prevention of postoperative adhesion is briefly introduced, and future research directions are discussed. [ABSTRACT FROM AUTHOR]

Currently, uncontrolled bleeding remains a serious problem in emergency, surgical and battlefield environments. Despite the specific properties of available hemostatic agents, sealants, and adhesives, effective hemostasis under wet and dynamic conditions remains a challenge. In recent years, polymeric hydrogels with excellent hemostatic properties have received much attention because of their adjustable mechanical properties, high porosity, and biocompatibility. In this review, to investigate the role of hydrogels in hemostasis, the mechanisms of hydrogel hemostasis and adhesion are firstly elucidated, the adhesion design strategies of hemostatic hydrogels in wet environments are briefly introduced, and then, based on a comprehensive literature review, the studies and in vivo applications of wet-adhesive hemostatic hydrogels in different environments are summarized, and the improvement directions of such hydrogels in future studies are proposed. [ABSTRACT FROM AUTHOR]

In recent years, multifunctional hydrogels have received a great deal of attention because they are biocompatible and can mimic the extracellular matrix. Herein, we prepared hydrogels of biocompatible cross-linked networks with photothermal properties. In this study, a chitosan/polyaniline/laponite (COL) hydrogel with photothermal conversion capability was designed. Polyaniline was firstly grafted onto chitosan and its solution was mixed with oxidized dextran, which was then cross-linked into a hydrogel via a Schiff base reaction. Furthermore, an aluminosilicate clay material, laponite (LAP), was incorporated into the hydrogel. The swelling ratio of the COL hydrogel in various solutions was greater than 580%, and it showed good degradation ability (the mass–loss ratio was over 45% after 28 days). This composite hydrogel was demonstrated to have good photothermal conversion properties and biocompatibility at both the cell (cell viability was over 97%) and animal levels. The COL hydrogel showed a photothermal conversion efficiency of 23.7% under the irradiation of a near-infrared laser. Coupled with the osteogenic differentiation-inducing potential of LAP, the COL hydrogel has the potential to kill tumors via hyperthermia or serve as scaffolds for bone tissue regeneration. [ABSTRACT FROM AUTHOR]

[Display omitted] • An injectable hydrogel to reduce the postoperative abdominal adhesion is designed. • A third-generation polyamide-amine dendrimer loads the Meloxicam for slow release. • The hydrogel has good in vitro and in vivo biosafety and biodegradability. • MX inhibits inflammatory responses and balances the fibrinolytic system. • The adhesion prevention is proved in a rat abdominal adhesion model. Establishing a physical barrier between the peritoneum and the cecum is an effective method to reduce the risk of postoperative abdominal adhesions. Meloxicam (MX), a nonsteroidal anti-inflammatory drug has also been applied to prevent postoperative adhesions. However, its poor water solubility has led to low bioavailability. Herein, we developed an injectable hydrogel as a barrier and drug carrier for simultaneous postoperative adhesion prevention and treatment. A third-generation polyamide-amine dendrimer (G3) was exploited to dynamically combine with MX to increase the solubility and the bioavailability. The formed G3@MX was further used to crosslink with poly-γ-glutamic acid (γ-PGA) to prepare a hydrogel (GP@MX hydrogel) through the amide bonding. In vitro and in vivo experiments evidenced that the hydrogel had good biosafety and biodegradability. More importantly, the prepared hydrogel could control the release of MX, and the released MX is able to inhibit inflammatory responses and balance the fibrinolytic system in the injury tissues in vivo. The tunable rheological and mechanical properties (compressive moduli: from ∼ 57.31 kPa to ∼ 98.68 kPa;) and high anti-oxidant capacity (total free radical scavenging rate of ∼ 94.56 %), in conjunction with their syringeability and biocompatibility, indicate possible opportunities for the development of advanced hydrogels for postoperative tissue adhesions management. [ABSTRACT FROM AUTHOR]

The rapid development of functional materials and manufacturing technologies is fostering advances in piezoelectric materials (PEMs). PEMs can convert mechanical energy into electrical energy. Unlike traditional power sources, which need to be replaced and are inconvenient to carry, PEMs have extensive potential applications in smart wearable and implantable devices. However, the application of conventional PEMs is limited by their poor flexibility, low ductility, and susceptibility to fatigue failure. Incorporating hydrogels, which are flexible, stretchable, and self-healing, providing a way to overcome these limitations of PEMs. Hydrogel-based piezoelectric materials (H-PEMs) not only resolve the shortcomings of traditional PEMs but also provide biocompatibility and more promising application potential. This paper summarizes the working principle of H-PEMs. Recent advances in the use of H-PEMs as sensors and in vitro energy harvesting devices for smart wearable devices are described in detail, with emphasis on application scenarios in human body like fingers, wrists, ankles, and feet. In addition, the recent progress of H-PEMs in implantable medical devices, especially the potential applications in human body parts such as bones, skin, and heart, are also elaborated. In addition, challenges and potential improvements in H-PEMs are discussed. [ABSTRACT FROM AUTHOR]

In this study, a methacrylic gelatin/oxidized dextran/montmorillonite‑strontium/polypyrrole (GOMP) hydrogel was prepared. The GOMP hydrogel had dual network structure which was formed through photoinitiator-initiated double bond polymerization and Schiff base reaction. The network structure led to a sustained release of the antitumor drug, doxorubicin (DOX). Polypyrrole introduced the conductivity and high photothermal conversion capacity to the GOMP hydrogel, which showed a photothermal conversion efficiency of 31.61 % under 808 nm laser radiation. The GOMP hydrogel had good swelling properties in solvents. Further study showed that the GOMP hydrogel had good biocompatibility and excellent biodegradability in vitro and in vivo. The experiments of in vitro tumor therapy and in vivo anti-tumor recurrence indicated that the DOX-loaded GOMP hydrogel had synergistic effects on tumor cell apoptosis based on chemotherapy and photothermal therapy. In addition, montmorillonite‑strontium (MMT-Sr) doped in the hydrogel not only improved the mechanical properties of the hydrogel but also promoted potential bone regeneration. The multifunctional DOX-loaded GOMP hydrogel with bone regeneration, photothermal therapy, and chemotherapy functions has great potential application for treating osteosarcoma. [ABSTRACT FROM AUTHOR]

Massive bleeding is a great threat to the life safety of patients, which is a challenging clinical problem. Therefore, it is urgent to develop a kind of multifunctional dressing material with hemostatic ability and antibacterial performance to promote wound healing and repair. To resolve this issue, in this study, a carboxymethyl chitosan (CMCS)/sodium alginate (SA)/oxidized dextran (ODE) (CSO) multifunctional hydrogel was developed. The hydrogel could rapidly gel through Schiff base reaction and amide reaction and firmly adhere to the skin at the wound, to realize the fast hemostasis. Importantly, it was verified that the hydrogel could prevent the Staphylococcus aureus -caused wound infection, owing to the antibacterial effect of CMCS and ODE. In addition, the CSO hydrogel had good water retention capacity and was able to mimic the three-dimensional structure of the natural extracellular matrix, thereby promoting wound repair in mice. In vitro whole-blood clotting assay demonstrated that red blood cells could be adhered to the surface of hydrogel, showing good hemostasis in rat liver injury and tail amputation models. Together with the biocompatible feature, CSO hydrogel holds a great application prospect in hemostasis and wound healing. • Carboxymethyl chitosan/sodium alginate/oxidized dextran hydrogel was prepared. • The hydrogel had excellent adhesion, mechanical properties and biodegradability. • The hydrogel could firmly adhere to the skin at the wound. • The hydrogel reduced the blood loss on rat liver injury and tail bleeding models. [ABSTRACT FROM AUTHOR]

Chitosan has been widely used in biomedical fields due to its good antibacterial properties, excellent biocompatibility, and biodegradability. In this study, a pH-responsive and self-healing hydrogel was synthesized from 3-carboxyphenylboronic acid grafted with chitosan (CS-BA) and polyvinyl alcohol (PVA). The dynamic boronic ester bonds and intermolecular hydrogen bonds are responsible for the hydrogel formation. By changing the mass ratio of CS-BA and PVA, the tensile stress and compressive stress of hydrogel can controlled in the range of 0.61 kPa - 0.74 kPa and 295.28 kPa - 1108.1 kPa, respectively. After doping with tannic acid (TA)/iron nanocomplex (TAFe), the hydrogel successful killed tumor cells through the near infrared laser-induced photothermal conversion and the TAFe-triggered reactive oxygen species generation. Moreover, the photothermal conversion of the hydrogel and the antibacterial effect of CS and TA give the hydrogel a good antibacterial effect. The CS-BA/PVA/TAFe hydrogel exhibit good in vivo and in vitro anti-tumor recurrence and antibacterial ability, and therefore has the potential to be used as a powerful tool for the prevention of local tumor recurrence and bacterial infection after surgery. [Display omitted] [ABSTRACT FROM AUTHOR]

In this study, a low-cost and high-performance MoS 2 /sodium alginate (SA)/Fe (MSF) hydrogel catalyst was prepared. It was found that the MSF hydrogel could efficiently catalyze the degradation of methylene blue (MB) through the Fenton reaction without the addition of Fe2+. The reaction was initiated by Fe2+ which was derived from the cyclic redox reaction between MoS 2 and Fe3+ and produced large quantities of ·OH to degrade the MB. The effect of MoS 2 concentration, FeCl 3 ·6H 2 O concentration, H 2 O 2 dosage, solution pH, and light on the degradation was systematically studied. The MoS 2 concentration of 0.5 mg/ mL, FeCl 3 ·6H 2 O concentration of 0.25 g/mL, 50 μL H 2 O 2 , and the pH of 4.0 were the optimized parameters. Moreover, it was found that the MB degraded faster under the infrared radiation. The MB removal rate reached as high as 98% within 15 min in the presence of a low concentration of H 2 O 2 and the procedure could be repeated 5 times. The MSF hydrogel provided an effective and simple strategy for the sustainable degradation of organic pollutants in wastewater. [Display omitted] • A low -cost and high-performance MoS 2 /sodium alginate (SA)/Fe (MSF) hydrogel was prepared as a catalyst. • Introducing MoS 2 improved the catalytic performance of the hydrogel. • The MSF hydrogel showed the good reusability for degradation of MB. [ABSTRACT FROM AUTHOR]

Hydrogels have been widely used as wound dressings to accelerate wound healing. However, due to the impaired skin barrier at the wound site, external bacteria can easily invade the wound and cause infection. In this study, we designed a dopamine-modified sodium alginate/carboxymethyl chitosan/polyvinylpyrrolidone (CPD) hydrogel, which was able to promote wound healing while preventing wound infection. Due to the high content of catechol groups, the CPD hydrogel exhibited good tissue adhesion ability and a significant scavenging ability for DPPH• and PTIO• radicals. Under near-infrared laser irradiation, the temperature of CPD hydrogel increased significantly, which significantly killed the Staphylococcus aureus and Escherichia coli. The cell migration test confirmed that CPD hydrogel could promote the cell migration ratio. In the in vivo wound healing test for infected full-thickness skin defect, CPD hydrogel significantly inhibited bacterial proliferation and enhanced wound healing rate. Therefore, the multifunctional hydrogel is expected to be applied to wound healing. [ABSTRACT FROM AUTHOR]

Benefiting from the biocompatibility, adhesiveness, and natural extracellular matrix-mimicking ability, hydrogels have received increasing research in recent years. In this study, a hydrogel system composed of dopamine, quaternized ammoniated chitosan (QCS), and polyvinylpyrrolidone was reported to exhibit fast hemostatic properties in Sprague-Dawley rat tail amputation and liver bleeding models. The results showed that this hydrogel had good hemostatic properties. The designed hydrogel showed high swelling ratios in H 2 O, PBS, and 0.9 % NaCl solution, indicating its capability to absorb tissue residual exudate and form a stable hydrogel. Compared with the control group, the blood loss in Sprague-Dawley rat tail amputation and liver bleeding were reduced by nearly 78 % and 76 %, respectively. Interestingly, dopamine endowed the hydrogel with antioxidant properties, thus holding a great application promise in inflammatory wounds. Furthermore, the designed hydrogel demonstrated good and reversible adhesion properties (12.23 ± 0.22 kPa–24.31 ± 0.55 kPa), ensuring its firm attachment to bleeding wounds of pig skin in wet environments. This research points out a novel path for designing chitosan-based hydrogels for biomedical applications. [Display omitted] • A hydrogel composed of dopamine, quaternized ammoniated chitosan, and polyvinylpyrrolidone was reported. • This hydrogel had excellent hemostatic properties. • Dopamine endowed the hydrogel with antioxidant properties. • The hydrogel demonstrated excellent and reversible adhesion properties. [ABSTRACT FROM AUTHOR]

We designed an injectable hydrogel by dissolving MoS 2 /Bi 2 S 3 -PEG (MBP), doxorubicin (DOX) and agar into water for the concurrent tumor photothermal and chemotherapy. The formed solution was able to be intra-tumorally (I.T.) administered into tumor at a relatively high temperature and automatically formed a hydrogel after cooling to body temperature. The resultant Agar/MBP/DOX (AMD) hydrogel can act as a macro-vessel to retain the MBP nanosheet and DOX and restrict their access to body fluid circulation. Moreover, AMD hydrogel did not compromise the photoacoustic and computed tomography imaging capacity, as well as the photothermal and chemotherapy efficiency of MBP nanosheets and DOX. The heat from the photothermal transformation of MBP nanosheet can promote the drug-release from the hydrogel and thus enable an on-demand drug release. Furthermore, antibiotics were also able to be encapsulated in the hydrogel to avoid the potential wound infection during tumor surgery. [ABSTRACT FROM AUTHOR]

In this study, a composite hydrogel (QMPD hydrogel) composed of methacrylate anhydride (MA) grafted quaternary ammonium chitosan (QCS-MA), polyvinylpyrrolidone (PVP), and dopamine (DA) was designed for the sequential wound inflammation elimination, infection inhibition, and wound healing. The QMPD hydrogel formation was initiated by the ultraviolet light-triggered polymerization of QCS-MA. Furthermore, hydrogen bonds, electrostatic interactions, and "π-π" stacking between QCS-MA, PVP, and DA were involved in the hydrogel formation. In this hydrogel, the quaternary ammonium groups of quaternary ammonium chitosan and the photothermal conversion of polydopamine are capable of killing bacteria on wounds, which showed the bacteriostatic ratios of 85.6 % and 92.5 % toward Escherichia coli and Staphylococcus aureus , respectively. Moreover, the oxidation of DA sufficiently scavenged free radicals and introduced the QMPD hydrogel with good anti-oxidant and anti-inflammatory abilities. Together with the extracellular matrix-mimic tropical structure, the QMPD hydrogel significantly promoted the wound management of mice. Therefore, the QMPD hydrogel is expected to provide a new method for the design of wound healing dressings. [ABSTRACT FROM AUTHOR]

Recently, the healing of chronic wounds such as extensive burns has become a serious and intractable clinical problem. Avoiding wound infection and retaining an appropriate level of moisture around wounds are significant challenges in wound care. Herein, a dual-network hydrogel composed of sodium alginate (SA) and platelet-rich plasma (PRP) was designed to facilitate the wound healing. The preparation of hydrogel was achieved through a simple one-step thrombin activation process. The morphological characterization results revealed the three-dimensional network structure of the hydrogel. Then, certain levels of epidermal growth factor (EGF) and vascular endothelial growth factor (VEGF) were detected in phosphate buffer solution (PBS) cultured hydrogel, which led to the possibility of cell proliferation and vascular regeneration. When topically applied to the wound skin of rats, the hydrogel presented high wound closure effectiveness. In conclusion, this strategy provides a simple and feasible approach to overcoming the shortcomings of conventional wound dressings. [Display omitted] • A dual-network hydrogel composed of sodium alginate and platelet-rich plasma. • The hydrogel releases epidermal growth and vascular endothelial growth factors. • The hydrogel presents high wound closure and wound healing effectiveness. [ABSTRACT FROM AUTHOR]

[Display omitted] • A biodegradable dopamine-modified sodium carboxymethyl cellulose hydrogel. • Sodium periodate was used to oxidize the CMC-DA for the hydrogel formation. • The formed NaI enables the CT imaging to monitor the degradation. • Ce6 was loaded by the hydrogel via soaking the hydrogel in the Ce6 solution. • Ce6 produced ROS and PDA produced heat for the combined tumor therapy. In this research, a hydrogel that combined the tumor photodynamic therapy (PDT) and photothermal therapy (PTT) ability was designed, using dopamine-modified sodium carboxymethyl cellulose (CMC-DA) as the matrix and Chlorin e6 (Ce6) as the photosensitizer. The gel formation was initiated by adding the oxidizing agent sodium periodate (NaIO 4) to the CMC-DA solution, during which the dopamine was simultaneously oxidized to polydopamine (PDA) and NaIO 4 was reduced to sodium iodide (NaI). The formed NaI was encapsulated in the hydrogel and endowed the hydrogel with computerized tomography (CT) imaging ability to monitor the hydrogel degradation and the tumor therapy process. Moreover, the photosensitizer Ce6 can be loaded by the gel system via directly soaking the hydrogel in the Ce6 solution. Under the near-infrared light irradiation, Ce6 can produce cytotoxic reactive oxygen species and the PDA can produce heat to trigger the tumor PDT and PTT respectively to eradicate the tumor recurrence. In general, the designed hydrogel is biocompatible and biodegradable, has a good photothermal conversion, drug loading and CT imaging ability, which laid the foundation for the rational design of biodegradable hydrogels for multifunctional applications. [ABSTRACT FROM AUTHOR]

An in-situ formed hemostatic hydrogel (GelMA/OD/Borax) was prepared for the emergency wound hemostasis and anti-inflammation applications. Gelatin was chosen as the backbone and modified with methacrylic anhydride (MA) to synthesize GelMA, which showed the admirable UV light activatable polymerizing ability. Aldehyde groups, which cross-linked with the -NH 2 on the tissue surface and afforded the tissue adhesion, were produced by oxidizing the o-hydroxyl groups of dextran. Further, the sodium tetraborate formed dynamic boric acid ester bonds with the oxidized dextran (OD). With this triple-network structure, the as-prepared hydrogel presented excellent hemostatic capacity and surmounted a high blood pressure of 165 mmHg, which is higher than the threshold systolic blood pressure of healthy adults (i.e., 120 mmHg). The mechanical property, morphology, biocompatibility and degradation of the hydrogel were character Borax, the hydrogel successfully blocked the bleeding and accelerated the wound healing. This research provides a new modality for the design of a multifunctional hemostatic hydrogel for effective hemostasis and wound healing. • GelMA/OD/Borax hydrogel is reported for the wound hemostasis and anti-inflammation. • The hemostatic hydrogel can surmount a high blood pressure of 165 mmHg. • The hydrogel is biocompatible, degradable, and has a good antibacterial capacity. • The hydrogel can accelerate the wound healing. [ABSTRACT FROM AUTHOR]

[Display omitted] • Bi3+ induces the gelatinization of ALG and reacts with Na 2 S. • The Bi 2 S 3 NPs enable the CT imaging and the enhancement of tumor RT. • The sensitized RT enhances the hypoxia of TME and activates TPZ. • The Bi 2 S 3 NPs generate the hyperthermia to eradicate the cancer cells. Radiotherapy (RT) is becoming a pervasive therapeutic pattern in clinical cancer therapy. However, the hypoxic microenvironment of tumors has a strong resistance to radiotherapy and could lead to a potential recurrence and metastasis after the treatment. Therefore, the use of synergistic strategies for improving and supplementing the RT efficiency is important. Herein, a novel Bi 2 S 3 /alginate (ALG) hydrogel containing tirapazamine (TPZ) was designed for the effective suppression of tumor recurrence, by introducing Bi3+ into the ALG, Na 2 S and TPZ solution. In this formulation, Bi3+ was used to crosslink with the ALG to form the hydrogel and react with S2− to simultaneously form Bi 2 S 3 nanoparticles in the hydrogel matrix. The resulting Bi 2 S 3 nanoparticles not only exhibit the superb radiosensitization effect to boost the effective eradication of tumors during RT but also manifest an excellent photothermal transforming performance for tumor hyperthermia and computed tomography (CT) imaging capacity for tumor monitoring. Furthermore, the RT caused hypoxia could activate the reductive prodrug TPZ and enhance its therapeutic efficiency. The reported hydrogel system provides an efficient and safe therapeutic strategy for current local tumor therapy. [ABSTRACT FROM AUTHOR]

• A simple method to synthesize MoS 2 and GOx-containing sodium alginate hydrogel. • The hydrogel consumes the glucose to lead to tumor starvation therapy. • The MAF hydrogel has a good photothermal conversion. • The generated Fe2+ induces a Fenton reaction for chemodynamic therapy of tumors. Starvation therapy (ST) and chemodynamic therapy (CDT) are emerging tumor therapy methods in recent years. In this study, a simple approach was reported to prepare MoS 2 and glucose oxidase (GOx)-containing sodium alginate (ALG)-Fe3+ (MAF) hydrogel. In the hydrogel, there exists an enzymatic reaction to consume glucose to form hydrogen peroxide (H 2 O 2), and a redox reaction between Fe3+ and MoS 2 to form Fe2+ and MoO 4 2−. The formed Fe2+ could be oxidized to Fe3+, which reacts with MAF hydrogel again to continuously produce Fe2+. The consumption of glucose resulted in an obvious tumor ST. Moreover, the produced Fe2+ induced a Fenton reaction to enable the persistent conversion of H 2 O 2 to cytotoxic hydroxyl radicals (·OH) for the CDT of tumors. Together with the high photothermal transforming capability of MoS 2 , the hydrogel was used for the combined tumor photothermal therapy (PTT), ST, and CDT. This work provides a window for the safe use of enzymes for achieving high tumor therapeutic efficacy. [ABSTRACT FROM AUTHOR]

• Chitosan-based composite hydrogel was designed for the synergistic photothermal- and chemotherapy of colon cancer. • The temperature-sensitive hydrogel could release drug in an on-demand manner. • Localized therapy with no harm to normal tissues and organs was achieved. • The chitosan-based hydrogel had antibacterial effects. The purpose of this study was to design an injectable hydrogel with temperature-sensitive property for safe and high efficient in vivo colon cancer hyperthermia and chemotherapy. Chitosan (CS) solution was injected into the tumor at room temperature and automatically gelled after warming to body temperature in the present of β-glycerophosphate (β-GP). Combined localized tumor photothermal and chemotherapy were achieved by dissolving photothermal material MoS 2 /Bi 2 S 3 -PEG (MBP) nanosheets and drug molecule doxorubicin (DOX) into the hydrogel, and the gel system could encapsulate DOX and MBP nanosheets and prevent them from entering the blood circulation and damaging normal tissues and cells. More importantly, the CS/MBP/DOX (CMD) hydrogel exhibited a photothermal efficiency of 22.18% and 31.42% in the first and second near infrared light (NIR I and NIR II) biowindows respectively at a low MBP concentration (0.5 mg/mL). Besides, the release of the DOX from CMD hydrogel was controllable since the gel temperature could be governed by NIR laser irradiation. Moreover, the chitosan-based hydrogel had antibacterial effects. The designed composite hydrogel is anticipated to act as a platform for the high efficient treatment of tumors owing to the different penetration depths of NIR I and NIR II. [ABSTRACT FROM AUTHOR]