In this study,the hydrogels composites with coatings based on a temperature-sensitive linear copolymer of N-tert-butylacrylamide(NTBA)and acrylamide(AAm)on cotton fabrics have been developed.The cotton fabrics were co...In this study,the hydrogels composites with coatings based on a temperature-sensitive linear copolymer of N-tert-butylacrylamide(NTBA)and acrylamide(AAm)on cotton fabrics have been developed.The cotton fabrics were coated using aqueous solution of the linear copolymer,1,2,3,4-butanetertracarboxylic acid(BTCA)as a cross-linker and sodium hypophosphite(SHP)as a catalyst,followed by drying and curing.The effects of cross-linking reaction conditions in coating process on water-impermeable ability of coated cotton fabrics were investigated in detail.The results indicate that the coated fabrics have temperature sensitivity.The coatings of poly(NTBA-co-AAm)hydrogels were bonded on the surface of the cotton fabrics,as verified by SEM and optical microscopy,which gave the water-impermeable ability to the hydrogels composites.Moreover,the hydrogels formed in the coating process also identified that - COOH of BTCA reacted with -NH2 in the linear polymer and formed three-dimensional network hydrogels.FTIR and XPS were used to characterize the cross-linking reaction of - COOH of BTCA and - OH of cellulose.展开更多
A kind of novel copolymer hydrogel of poly（N, N-dimethylaminoethyl methacrylate-co-N-isopropylacrylamide） （poly[DMAEMA/NIPAAm]） was synthesized by the initiation of K2S2O8, N, N＇-methylene-bis（acrylamide） （Bis...A kind of novel copolymer hydrogel of poly（N, N-dimethylaminoethyl methacrylate-co-N-isopropylacrylamide） （poly[DMAEMA/NIPAAm]） was synthesized by the initiation of K2S2O8, N, N＇-methylene-bis（acrylamide） （Bis） was used as the crosslinker. The effects of monomer content, pH and temperature on swelling ratio of the hydrogel were investigated; the thermo-sensitivity in deionized water and in physiological saline was determined. It showed that the swelling ratio of the hydrogel could be changed by changing the temperature or pH alternately. Both swelling ratio and LCST （Lower Critical Solution Temperature） of the hydrogel decreased with the increase of NIPAAm in the co-polymer content.展开更多
We proposed a strategy using high-concentration tannic acid(TA) solutions to form robust and dense supramolecular networks in hydrogels,driven by the high osmotic pressure of the TA solution.The resulting hydrogels ar...We proposed a strategy using high-concentration tannic acid(TA) solutions to form robust and dense supramolecular networks in hydrogels,driven by the high osmotic pressure of the TA solution.The resulting hydrogels are both transparent and tough,with highly compacted networks.The hydrogels exhibit an ultimate tensile strength of approximately 4.55 MPa and a toughness of 160 MJ/m^(3).Additionally,the hydrogels adhere to a wide range of substrates,including metals,ceramics,glass,and even Teflon,with an adhesion strength of up to 42 kPa on Teflon plates.Given the biocompatibility and biodegradability of both PVA and TA,along with the hydrogels' toughness,transparency,and adhesiveness,we anticipated broad applications in the biomedical field,such as in articular cartilage restoration,electronic skin,and wound dressings.Additionally,these hydrogels hold significant potential for applications in wearable technology and optoelectronic devices.展开更多
Lignin,the most abundant natural aromatic polymer globally,has garnered considerable interest due to its rich and diverse active functional groups and its antioxidant,antimicrobial,and adhesive properties.Recent resea...Lignin,the most abundant natural aromatic polymer globally,has garnered considerable interest due to its rich and diverse active functional groups and its antioxidant,antimicrobial,and adhesive properties.Recent research has significantly improved the performance of lignin-based hydrogels,suggesting their substantial potential in fields such as biomedicine,environmental science,and agriculture.This paper reviews the process of lignin extraction,systematically introduces synthesis strategies for preparing lignin-based hydrogels,and discusses the current state of research on these hydrogels in biomedical and environmental protection fields.It concludes by identifying the existing challenges in lignin hydrogel research and envisioning future prospects and development trends.展开更多
Burn infection is one of the most common and severe complications in burn patients and a major factor contributing to high mortality rates.The loss of skin barrier function and the immunosuppressive state following bu...Burn infection is one of the most common and severe complications in burn patients and a major factor contributing to high mortality rates.The loss of skin barrier function and the immunosuppressive state following burns make patients highly susceptible to wound infections,which can progress to systemic sepsis.Although burn wounds are initially sterile,they are rapidly colonized by Gram-positive bacteria(e.g.,Staphylococcus aureus)within a short period,followed by colonization with Gram-negative bacteria(e.g.,Pseudomonas aeruginosa),thereby increasing therapeutic challenges.Current clinical management relies on a multidisciplinary collaborative approach,combining conventional antibiotics,emerging therapies,and comprehensive care strategies.Among these methods,early intervention,precise treatment administration,and prevention and control are critical to improving patient survival and prognosis.In recent years,drug-loaded hydrogels,as a class of wound repair materials characterized by biocompatibility,controlled drug release,and multifunctional integration,have demonstrated significant advantages in the treatment of burn infections.They can effectively inhibit pathogenic microorganisms,alleviate inflammation,and promote tissue regeneration.This review systematically summarizes recent research advances in the application of drug-loaded hydrogels for the treatment of infected burn wounds,aiming to provide a reference for their further development and clinical translation.展开更多
Green solvent pretreatment of biomass represents a promising ap-proach for enhancing the econom-ic value of lignocellulosic deriva-tives.In this study,corncob biomass was treated with a diol-based deep eutectic solven...Green solvent pretreatment of biomass represents a promising ap-proach for enhancing the econom-ic value of lignocellulosic deriva-tives.In this study,corncob biomass was treated with a diol-based deep eutectic solvent(DES)under mild conditions,facilitating efficient cellulose separation.The extracted cellulose was subsequently used to fabricate cellulose hydrogels in an aqueous zinc chloride solution.The resulting hydrogel exhibited a“water-in-salt”effect due to the high concentration of ZnCl_(2).Leveraging the antifreeze properties of sorbitol,the system demon-strated outstanding low-temperature electrochemical performance,including a broad operat-ing voltage window and an ionic conductivity of 38.4 mS·cm^(-1)at-20℃.At 20℃,the de-vice achieved an energy density of 206 Wh·kg^(-1)and a power density of 2701.05 W·kg^(-1)at a current density of 1 A·g^(-1).Moreover,the flexible zinc-ion hybrid supercapacitor(ZHSC)maintained 89%of its capacitance and nearly 100%Coulombic efficiency after 5500 cycles at 20℃.This work not only advances the development of zinc-ion energy storage devices but al-so establishes a new paradigm for the green and direct utilization of biomass-derived materi-als.展开更多
The osteochondral(OC)interface exhibits a mineral gradient,varying in thickness by several hundred micrometers across different species.Disruptions in this interface damage OC tissues,leading to osteoarthritis.The nat...The osteochondral(OC)interface exhibits a mineral gradient,varying in thickness by several hundred micrometers across different species.Disruptions in this interface damage OC tissues,leading to osteoarthritis.The natural architecture and composition of native OC interfaces can be replicated using biomaterial scaffolds via regenerative engineering approaches.A novel one-step bioextrusion process was employed to fabricate a unitary synthetic graft(USG),which mimics the native OC interface’s mineral concentration gradient.This novel USG is composed of an agarose-based cartilage layer and a bone layer,consisting of agarose enriched with 20%(200 g/L)hydroxyapatite.The USG features a gradient interface with mineral concentrations transitioning from 0%to 20%(mass fraction),mimicking the transition between the cartilage and bone.Thermogravimetric analysis revealed that the gradient transition lengths of the graft and native OC tissue harvested from bovine knees were similar((647±21)vs.(633±124)μm).The linear viscoelastic properties of the grafts,which were evaluated using strain sweep and frequency sweep tests with oscillatory shear,indicated a dominant storage modulus over loss modulus similar to that of native OC tissues.The compressive and stress relaxation behaviors of the USGs demonstrated that the graft maintained structural integrity under mechanical stress.Viability assays performed after bioextrusion showed that chondrocytes and human fetal osteoblast cells successfully integrated and survived within their designated regions of the graft.The novel USGs exhibit properties similar to native OC tissue and are promising candidates for regenerating OC defects and restoring knee joint functionality.展开更多
The continuous extension of human life expectancy and the global trend of population aging have contributed to a marked increase in the incidence of musculoskeletal diseases,with fractures and osteoporosis being promi...The continuous extension of human life expectancy and the global trend of population aging have contributed to a marked increase in the incidence of musculoskeletal diseases,with fractures and osteoporosis being prominent examples.Consequently,promoting bone regeneration is a crucial medical challenge that demands immediate attention.As early as the mid-20th century,researchers revealed that electrical stimulation could effectively promote the healing and regeneration of bone tissue.This is achieved by mimicking the endogenous electric field within bone tissue,which influences cellular behavior and molecular mechanisms.In recent years,electroactive hydrogels responsive to electric field stimulation have been developed and applied to regulate cell functions at different stages of bone regeneration.This paper elaborates on the regulatory effects of electrical stimulation on MSCs,macrophages,and vascular endothelial cells during the process of bone regeneration.It also involves the activation of relevant ion channels and signaling pathways.Subsequently,it comprehensively reviews various electric-field-responsive hydrogels developed in recent years,covering aspects such as material selection,preparation methods,characteristics,and their applications in bone regeneration.Ultimately,it provides an objective summary of the existing deficiencies in hydrogel materials and research,and looks ahead to future development directions.展开更多
Post-traumatic stress disorder(PTSD)is a psychiatric disease that seriously affects brain function.Currently,selective serotonin reuptake inhibitors(SSRIs)are used to treat PTSD clinically but have decreased efficienc...Post-traumatic stress disorder(PTSD)is a psychiatric disease that seriously affects brain function.Currently,selective serotonin reuptake inhibitors(SSRIs)are used to treat PTSD clinically but have decreased efficiency and increased side effects.In this study,nasal cannabidiol inclusion complex temperature-sensitive hydrogels(CBD TSGs)were prepared and evaluated to treat PTSD.Mice model of PTSD was established with conditional fear box.CBD TSGs could significantly improve the spontaneous behavior,exploratory spirit and alleviate tension in open field box,relieve anxiety and tension in elevated plus maze,and reduce the freezing time.Hematoxylin and eosin and c-FOS immunohistochemistry slides showed that the main injured brain areas in PTSD were the prefrontal cortex,amygdala,and hippocampus CA1.CBD TSGs could reduce the level of tumor necrosis factor-a caused by PTSD.Western blot analysis showed that CBD TSGs increased the expression of the 5-HT1 A receptor.Intranasal administration of CBD TSGs was more efficient and had more obvious brain targeting effects than oral administration,as evidenced by the pharmacokinetics and brain tissue distribution of CBD TSGs.Overall,nasal CBD TSGs are safe and effective and have controlled release.There are a novel promising option for the clinical treatment of PTSD.展开更多
Semi-interpenetrating （semi-IPNs） hydrogels containing biocompatible silk sericin （SS） and poly（N-isopropylacrylamide）（PNIPAM） were prepared as novel cellular matrices. Their maximum swelling degree and basic ...Semi-interpenetrating （semi-IPNs） hydrogels containing biocompatible silk sericin （SS） and poly（N-isopropylacrylamide）（PNIPAM） were prepared as novel cellular matrices. Their maximum swelling degree and basic characteristics for biomedical applications such as mouse ？broblasts （L929） cell proliferation and desorption were investigated. The results showed that the incorporation of high hydrophilic SS into PNIPAM hydrogel increased the maximum swelling degree of the semi-IPNs hydrogels, and the adhesion and growth of the L929 on semi-IPNs hydrogels were at least comparable to, or even better than, that on conventional PNIPAM hydrogel. In addition, L929 cells were found to detach from the hydrogels surface naturally by controlling environmental temperature. These results suggest great potential of semi-IPNs hydrogels in tissue engineering.展开更多
Flexible hydrogels have shown promise as strain sensors in medical monitoring,human motion detection and intelligent robotics.For a hydrogel strain sensor,certain challenges need to be urgently addressed for practical...Flexible hydrogels have shown promise as strain sensors in medical monitoring,human motion detection and intelligent robotics.For a hydrogel strain sensor,certain challenges need to be urgently addressed for practical applications,such as the damage caused by external effects,leading to equipment failure,and the inability to perceive ambient temperature,resulting in single functionality.Herein,a stretchable,self-healing and dual temperature-strain sensitive hydrogel,with a physically-crosslinked network,is designed by constructing multiple dynamic reversible bonds.Graphene oxide(GO)and iron ions(Fe^(3+))act as dynamic bridges in the cross-linked network and are mediated by the covalent and hydrogen bonding,rendering excellent stretchability to the hydrogel.The reversible features of coordination interactions and hydrogen interactions endow excellent recoverability and self-healing properties.Moreover,the incorporated N-isopropyl acrylamide(NIPAM)provides excellent temperature responsiveness to the hydrogel,facilitating the detection of external temperature changes.Meanwhile,the hydrogels exhibited strain-sensitivity,with a wide working range of 1%-300%,fast response and electrical stability,which can be used as flexible sensors to monitor body motions,e.g.,speaking and the bending of finger,wrist,elbow and knee.Overall,the hydrogel possesses dual sensory capabilities,combining external temperature and strain,for potential applications in wearable multifunctional sensing devices.展开更多
All-season thermal management with zero energy consumption and emissions is more crucial to global decarbonization over traditional energy-intensive cooling/heating systems.However,the static single thermal management...All-season thermal management with zero energy consumption and emissions is more crucial to global decarbonization over traditional energy-intensive cooling/heating systems.However,the static single thermal management for cooling or heating fails to self-regulate the temperature in dynamic seasonal temperature condition.Herein,inspired by the dual-temperature regulation function of the fur color changes on the backs and abdomens of penguins,a smart thermal management composite hydrogel(PNA@H-PM Gel)system was subtly created though an"on-demand"dual-layer structure design strategy.The PNA@H-PM Gel system features synchronous solar and thermal radiation modulation as well as tunable phase transition temperatures to meet the variable seasonal thermal requirements and energy-saving demands via self-adaptive radiative cooling and solar heating regulation.Furthermore,this system demonstrates superb modulations of both the solar reflectance(ΔR=0.74)and thermal emissivity(ΔE=0.52)in response to ambient temperature changes,highlighting efficient temperature regulation with average radiative cooling and solar heating effects of 9.6℃in summer and 6.1℃in winter,respectively.Moreover,compared to standard building baselines,the PNA@H-PM Gel presents a more substantial energy-saving cooling/heating potentials for energy-efficient buildings across various regions and climates.This novel solution,inspired by penguins in the real world,will offer a fresh approach for producing intelligent,energy-saving thermal management materials,and serve for temperature regulation under dynamic climate conditions and even throughout all seasons.展开更多
Temperature-sensitive hydrogel—poly(N-isopropyl acrylamide) (PNIPA) was prepared and applied to protein refolding. PNIPA gel disks and gel particles were synthesized by the solution polymerization and inverse suspens...Temperature-sensitive hydrogel—poly(N-isopropyl acrylamide) (PNIPA) was prepared and applied to protein refolding. PNIPA gel disks and gel particles were synthesized by the solution polymerization and inverse suspension polymerization respectively. The swelling kinetics of the gels was also studied. With these prepared PNIPA gels, the model protein lysozyme was renatured. Within 24h, PNIPA gel disks improved the yield of lysozyme activity by 49.3% from 3375.2U·mg^-1 to 5038.8U·mg^-1. With the addition of faster response PNIPA gel beads, the total lysozyme activity recovery was about 68.98% in 3h, as compared with 42.03% by simple batch dilution. The novel refolding system with PNIPA enables efficient refolding especially at high protein concentrations. Discussion about the mechanism revealed that when PNIPA gels were added into the refolding buffer, the hydrophobic interactions between denatured proteins and polymer gels could prevent the aggregation of refolding intermediates, thus enhanced the protein renaturation.展开更多
Despite the promising progress in conductive hydrogels made with pure conducting polymer,great challenges remain in the interface adhesion and robustness in longterm monitoring.To address these challenges,Prof.Seung H...Despite the promising progress in conductive hydrogels made with pure conducting polymer,great challenges remain in the interface adhesion and robustness in longterm monitoring.To address these challenges,Prof.Seung Hwan Ko and Taek-Soo Kim’s team introduced a laserinduced phase separation and adhesion method for fabricating conductive hydrogels consisting of pure poly(3,4-ethylenedioxythiophene):polystyrene sulfonate on polymer substrates.The laser-induced phase separation and adhesion treated conducting polymers can be selectively transformed into conductive hydrogels that exhibit wet conductivities of 101.4 S cm^(−1) with a spatial resolution down to 5μm.Moreover,they maintain impedance and charge-storage capacity even after 1 h of sonication.The micropatterned electrode arrays demonstrate their potential in long-term in vivo signal recordings,highlighting their promising role in the field of bioelectronics.展开更多
The swelling behavior of a temperature-sensitive poly-N-isopropylacrylamide(PNIPAM) hydrogel circular cylinder is studied subjected to combined extension-torsion and varied temperature. In this regard, a semi-analytic...The swelling behavior of a temperature-sensitive poly-N-isopropylacrylamide(PNIPAM) hydrogel circular cylinder is studied subjected to combined extension-torsion and varied temperature. In this regard, a semi-analytical solution is proposed for general combined loading. A finite element(FE) analysis is conducted, subjecting a hydrogel cylinder to the combined extension-torsion and the varied temperature to evaluate the validity and accuracy of the solution. A user-defined UHYPER subroutine is developed and verified under free and constrained swelling conditions. The FE results illustrate excellent agreement with the semi-analytical solution. Due to the complexity of the problem, some compositions and applied loading factors are analyzed. It is revealed that for larger cross-linked density and larger ending temperature, the cylinder yields higher stresses and smaller radial swelling deformation. Besides, the radial and hoop stresses increase by applying larger twist and axial stretch. The hoop stresses intersect at approximately R/Rout = 0.58, where the hoop stress vanishes. Besides, the axial force has direct and inverse relationships with the axial stretch and the twist, respectively. However, the resultant torsional moment behavior is complex, and the position of the maximum point varies significantly by altering the axial stretch and the twist.展开更多
Hydrogels, as a novel class of biomaterials, exhibit broad application prospects and are widely used in tissue engineering. In the field of periodontology within dental medicine, hydrogels can be employed for periodon...Hydrogels, as a novel class of biomaterials, exhibit broad application prospects and are widely used in tissue engineering. In the field of periodontology within dental medicine, hydrogels can be employed for periodontal tissue regeneration to repair the damage caused by periodontitis. At present, various hydrogels have been developed to control periodontal inflammation and repair periodontal tissues. This article, based on domestic and international literature, provides a brief review of hydrogels used in periodontal tissue regeneration.展开更多
Insulin is an essential and versatile protein taking part in the control of blood glucose levels and protein anabolism.However,under prolonged storage or high temperature stress,insulin tends to unfold and aggregate i...Insulin is an essential and versatile protein taking part in the control of blood glucose levels and protein anabolism.However,under prolonged storage or high temperature stress,insulin tends to unfold and aggregate into toxic amyloid fibrils,leading to loss of physiological function.Inspired by natural chaperones,a series of temperature-sensitive polycaprolactone-based micelles were designed to prevent insulin from deactivation.The micelles were fabricated through the self-assembly of amphiphilic copolymers of methoxy poly(ethylene glycol)-poly(4-diethylformamide caprolactone-co-caprolactone)(mPEG_(17)-P(DECL-co-CL)),which had a regular spherical morphology with particle sizes of about 100 nm.In addition,the lower critical solution temperature(LCST)of the micelles could be tuned to 9 and 29℃by changing the ratio of DECL to CL.Benefiting from the temperature-sensitivity of DECL segment,the binding ability of micelles to insulin could be modulated by changing the temperature.Above LCST,micelles effectively inhibited insulin aggregation and protected it from thermal inactivation due to the strong binding ability between the hydrophobic segment DECL and insulin.Below LCST,DECL segment returned to hydrophilic and bound weakly with insulin,leading to the release of insulin and assisting in its recovery of secondary structure.Thus,these temperature-sensitive micelles provided an effective strategy for insulin protection.展开更多
In the current transformative era of biomedicine,hydrogels have established their presence in biomaterials due to their superior biocompatibility,tuneability and resemblance with native tissue.However,hydrogels typica...In the current transformative era of biomedicine,hydrogels have established their presence in biomaterials due to their superior biocompatibility,tuneability and resemblance with native tissue.However,hydrogels typically exhibit poor conductivity due to their hydrophilic polymer structure.Electrical conductivity provides an important enhancement to the properties of hydrogel-based systems in various biomedical applications such as drug delivery and tissue engineering.Consequently,researchers are developing combinatorial strategies to develop electrically responsive“SMART”systems to improve the therapeutic efficacy of biomolecules.Electrically conductive hydrogels have been explored for various drug delivery applications,enabling higher loading of therapeutic cargo with on-demand delivery.This review emphasizes the properties,mechanisms,fabrication techniques and recent advancements of electrically responsive“SMART”systems aiding on-site drug delivery applications.Additionally,it covers prospects for the successful translation of these systems into clinical research.展开更多
Enhancing gelatin methacryloyl(GelMA)hydrogel mechanics without compromising biocompatibility remains challenging,as conventional chemical crosslinking often disrupts degradation behavior.A cooling-induced entan-gleme...Enhancing gelatin methacryloyl(GelMA)hydrogel mechanics without compromising biocompatibility remains challenging,as conventional chemical crosslinking often disrupts degradation behavior.A cooling-induced entan-glement strategy effectively improves mechanical performance while preserving biological properties;however,its underlying mechanisms remain unclear.This study demonstrates that extended cooling durations significantly enhance the mechanical properties of GelMA hydrogels.Microstructural analyses reveal cooling-induced forma-tion of compact polymer networks with reduced mesh sizes.Molecular dynamics(MD)simulations confirm that the cooling process promotes topological entanglements that govern mechanical reinforcement.Guided by these insights,we propose a theoretical model to predict the stress responses of GelMA hydrogels under various cooling durations,establishing quantitative correlations between entanglement mechanisms and mechanical outcomes.This study provides a fundamental understanding of the interplay between cooling conditions,microstructure,and mechanical performance,offering a robust framework for designing GelMA hydrogels with optimized me-chanical properties for advanced biomedical applications.展开更多
Traditional hydrogels are inevitably damaged during practical applications,resulting in a gradual deterioration of their functional efficacy.A primary strategy to address this issue involves developing hydrogels with ...Traditional hydrogels are inevitably damaged during practical applications,resulting in a gradual deterioration of their functional efficacy.A primary strategy to address this issue involves developing hydrogels with inherent self-healing properties.In this study,we report the synthesis of self-healing polyacrylate hydrogels that integrate zwitterions,hydrophilic nano-silica and aluminum ions.Due to the synergistic effect of multiple hydrogen bonds,coordination bonds and electrostatic interactions,the tensile strength of the hydrogel is enhanced from 15.1 to 162.6 kPa.Moreover,the electrical resistance and tensile strength of the hydrogel can almost recover to its initial values after 20 min of healing at room temperature,exhibiting remarkable self-healing performance.Furthermore,the zwitterionic polyacrylate hydrogel serves as a wearable sensor with the capability of accurately response to the bending and stretching of human joints,exhibting a gauge factor of 1.87 under tensile strain ranging from 80% to 100%.Even after being freezed at-20℃ for 3 h,the zwitterionic polyacrylate hydrogel retains its exceptional writing performance.In conclusion,the hydrogels developed in this study demonstrate significant potential for wearable electronics applications.展开更多
基金Research Fund for the Doctoral Programof Higher Education of China(No.20050058006)
文摘In this study,the hydrogels composites with coatings based on a temperature-sensitive linear copolymer of N-tert-butylacrylamide(NTBA)and acrylamide(AAm)on cotton fabrics have been developed.The cotton fabrics were coated using aqueous solution of the linear copolymer,1,2,3,4-butanetertracarboxylic acid(BTCA)as a cross-linker and sodium hypophosphite(SHP)as a catalyst,followed by drying and curing.The effects of cross-linking reaction conditions in coating process on water-impermeable ability of coated cotton fabrics were investigated in detail.The results indicate that the coated fabrics have temperature sensitivity.The coatings of poly(NTBA-co-AAm)hydrogels were bonded on the surface of the cotton fabrics,as verified by SEM and optical microscopy,which gave the water-impermeable ability to the hydrogels composites.Moreover,the hydrogels formed in the coating process also identified that - COOH of BTCA reacted with -NH2 in the linear polymer and formed three-dimensional network hydrogels.FTIR and XPS were used to characterize the cross-linking reaction of - COOH of BTCA and - OH of cellulose.
文摘A kind of novel copolymer hydrogel of poly（N, N-dimethylaminoethyl methacrylate-co-N-isopropylacrylamide） （poly[DMAEMA/NIPAAm]） was synthesized by the initiation of K2S2O8, N, N＇-methylene-bis（acrylamide） （Bis） was used as the crosslinker. The effects of monomer content, pH and temperature on swelling ratio of the hydrogel were investigated; the thermo-sensitivity in deionized water and in physiological saline was determined. It showed that the swelling ratio of the hydrogel could be changed by changing the temperature or pH alternately. Both swelling ratio and LCST （Lower Critical Solution Temperature） of the hydrogel decreased with the increase of NIPAAm in the co-polymer content.
基金Funded by the Guangdong Major Project of Basic and Applied Basic Research(No.2021B0301030001)the National Key Research and Development Program of China(No. 2021YFB3802300)the National Natural Science Foundation of China(Nos. 52403153 and 52203169)。
文摘We proposed a strategy using high-concentration tannic acid(TA) solutions to form robust and dense supramolecular networks in hydrogels,driven by the high osmotic pressure of the TA solution.The resulting hydrogels are both transparent and tough,with highly compacted networks.The hydrogels exhibit an ultimate tensile strength of approximately 4.55 MPa and a toughness of 160 MJ/m^(3).Additionally,the hydrogels adhere to a wide range of substrates,including metals,ceramics,glass,and even Teflon,with an adhesion strength of up to 42 kPa on Teflon plates.Given the biocompatibility and biodegradability of both PVA and TA,along with the hydrogels' toughness,transparency,and adhesiveness,we anticipated broad applications in the biomedical field,such as in articular cartilage restoration,electronic skin,and wound dressings.Additionally,these hydrogels hold significant potential for applications in wearable technology and optoelectronic devices.
基金supported by the National Natural Science Foundation of China(21706052,22278114)Natural Science Foundation of Henan Province(242300421575).
文摘Lignin,the most abundant natural aromatic polymer globally,has garnered considerable interest due to its rich and diverse active functional groups and its antioxidant,antimicrobial,and adhesive properties.Recent research has significantly improved the performance of lignin-based hydrogels,suggesting their substantial potential in fields such as biomedicine,environmental science,and agriculture.This paper reviews the process of lignin extraction,systematically introduces synthesis strategies for preparing lignin-based hydrogels,and discusses the current state of research on these hydrogels in biomedical and environmental protection fields.It concludes by identifying the existing challenges in lignin hydrogel research and envisioning future prospects and development trends.
基金Supported by Natural Science Foundation of Guangxi(2025GXNSFHA069111,2020GXNSFAA159033,2019GXNSFAA245078)National Undergraduate Innovation and Entrepreneurship Training Program(202410601054).
文摘Burn infection is one of the most common and severe complications in burn patients and a major factor contributing to high mortality rates.The loss of skin barrier function and the immunosuppressive state following burns make patients highly susceptible to wound infections,which can progress to systemic sepsis.Although burn wounds are initially sterile,they are rapidly colonized by Gram-positive bacteria(e.g.,Staphylococcus aureus)within a short period,followed by colonization with Gram-negative bacteria(e.g.,Pseudomonas aeruginosa),thereby increasing therapeutic challenges.Current clinical management relies on a multidisciplinary collaborative approach,combining conventional antibiotics,emerging therapies,and comprehensive care strategies.Among these methods,early intervention,precise treatment administration,and prevention and control are critical to improving patient survival and prognosis.In recent years,drug-loaded hydrogels,as a class of wound repair materials characterized by biocompatibility,controlled drug release,and multifunctional integration,have demonstrated significant advantages in the treatment of burn infections.They can effectively inhibit pathogenic microorganisms,alleviate inflammation,and promote tissue regeneration.This review systematically summarizes recent research advances in the application of drug-loaded hydrogels for the treatment of infected burn wounds,aiming to provide a reference for their further development and clinical translation.
基金supported by the National Key R&D Program of China(No.2023YFA1507500)the Nation-al Natural Science Foundation of China(No.52373159)。
文摘Green solvent pretreatment of biomass represents a promising ap-proach for enhancing the econom-ic value of lignocellulosic deriva-tives.In this study,corncob biomass was treated with a diol-based deep eutectic solvent(DES)under mild conditions,facilitating efficient cellulose separation.The extracted cellulose was subsequently used to fabricate cellulose hydrogels in an aqueous zinc chloride solution.The resulting hydrogel exhibited a“water-in-salt”effect due to the high concentration of ZnCl_(2).Leveraging the antifreeze properties of sorbitol,the system demon-strated outstanding low-temperature electrochemical performance,including a broad operat-ing voltage window and an ionic conductivity of 38.4 mS·cm^(-1)at-20℃.At 20℃,the de-vice achieved an energy density of 206 Wh·kg^(-1)and a power density of 2701.05 W·kg^(-1)at a current density of 1 A·g^(-1).Moreover,the flexible zinc-ion hybrid supercapacitor(ZHSC)maintained 89%of its capacitance and nearly 100%Coulombic efficiency after 5500 cycles at 20℃.This work not only advances the development of zinc-ion energy storage devices but al-so establishes a new paradigm for the green and direct utilization of biomass-derived materi-als.
基金supported by the School of Engineering and Digital Sciences of Nazarbayev University,Astana,Kazakhstan(to CE)。
文摘The osteochondral(OC)interface exhibits a mineral gradient,varying in thickness by several hundred micrometers across different species.Disruptions in this interface damage OC tissues,leading to osteoarthritis.The natural architecture and composition of native OC interfaces can be replicated using biomaterial scaffolds via regenerative engineering approaches.A novel one-step bioextrusion process was employed to fabricate a unitary synthetic graft(USG),which mimics the native OC interface’s mineral concentration gradient.This novel USG is composed of an agarose-based cartilage layer and a bone layer,consisting of agarose enriched with 20%(200 g/L)hydroxyapatite.The USG features a gradient interface with mineral concentrations transitioning from 0%to 20%(mass fraction),mimicking the transition between the cartilage and bone.Thermogravimetric analysis revealed that the gradient transition lengths of the graft and native OC tissue harvested from bovine knees were similar((647±21)vs.(633±124)μm).The linear viscoelastic properties of the grafts,which were evaluated using strain sweep and frequency sweep tests with oscillatory shear,indicated a dominant storage modulus over loss modulus similar to that of native OC tissues.The compressive and stress relaxation behaviors of the USGs demonstrated that the graft maintained structural integrity under mechanical stress.Viability assays performed after bioextrusion showed that chondrocytes and human fetal osteoblast cells successfully integrated and survived within their designated regions of the graft.The novel USGs exhibit properties similar to native OC tissue and are promising candidates for regenerating OC defects and restoring knee joint functionality.
基金supported by the National Science Foundation of China(No.82272491)。
文摘The continuous extension of human life expectancy and the global trend of population aging have contributed to a marked increase in the incidence of musculoskeletal diseases,with fractures and osteoporosis being prominent examples.Consequently,promoting bone regeneration is a crucial medical challenge that demands immediate attention.As early as the mid-20th century,researchers revealed that electrical stimulation could effectively promote the healing and regeneration of bone tissue.This is achieved by mimicking the endogenous electric field within bone tissue,which influences cellular behavior and molecular mechanisms.In recent years,electroactive hydrogels responsive to electric field stimulation have been developed and applied to regulate cell functions at different stages of bone regeneration.This paper elaborates on the regulatory effects of electrical stimulation on MSCs,macrophages,and vascular endothelial cells during the process of bone regeneration.It also involves the activation of relevant ion channels and signaling pathways.Subsequently,it comprehensively reviews various electric-field-responsive hydrogels developed in recent years,covering aspects such as material selection,preparation methods,characteristics,and their applications in bone regeneration.Ultimately,it provides an objective summary of the existing deficiencies in hydrogel materials and research,and looks ahead to future development directions.
基金funded by the Beijing Municipal Natural Science Foundation,China(7202147 and 7172072,China)
文摘Post-traumatic stress disorder(PTSD)is a psychiatric disease that seriously affects brain function.Currently,selective serotonin reuptake inhibitors(SSRIs)are used to treat PTSD clinically but have decreased efficiency and increased side effects.In this study,nasal cannabidiol inclusion complex temperature-sensitive hydrogels(CBD TSGs)were prepared and evaluated to treat PTSD.Mice model of PTSD was established with conditional fear box.CBD TSGs could significantly improve the spontaneous behavior,exploratory spirit and alleviate tension in open field box,relieve anxiety and tension in elevated plus maze,and reduce the freezing time.Hematoxylin and eosin and c-FOS immunohistochemistry slides showed that the main injured brain areas in PTSD were the prefrontal cortex,amygdala,and hippocampus CA1.CBD TSGs could reduce the level of tumor necrosis factor-a caused by PTSD.Western blot analysis showed that CBD TSGs increased the expression of the 5-HT1 A receptor.Intranasal administration of CBD TSGs was more efficient and had more obvious brain targeting effects than oral administration,as evidenced by the pharmacokinetics and brain tissue distribution of CBD TSGs.Overall,nasal CBD TSGs are safe and effective and have controlled release.There are a novel promising option for the clinical treatment of PTSD.
文摘Semi-interpenetrating （semi-IPNs） hydrogels containing biocompatible silk sericin （SS） and poly（N-isopropylacrylamide）（PNIPAM） were prepared as novel cellular matrices. Their maximum swelling degree and basic characteristics for biomedical applications such as mouse ？broblasts （L929） cell proliferation and desorption were investigated. The results showed that the incorporation of high hydrophilic SS into PNIPAM hydrogel increased the maximum swelling degree of the semi-IPNs hydrogels, and the adhesion and growth of the L929 on semi-IPNs hydrogels were at least comparable to, or even better than, that on conventional PNIPAM hydrogel. In addition, L929 cells were found to detach from the hydrogels surface naturally by controlling environmental temperature. These results suggest great potential of semi-IPNs hydrogels in tissue engineering.
基金financially supported by the National Natural Science Foundation of China(No.52173301)International Science and Technology Cooperation Project of Sichuan Province(No.2022YFH0019)Innovative Research Team of Southwest Petroleum University(No.2017CXTD01)。
文摘Flexible hydrogels have shown promise as strain sensors in medical monitoring,human motion detection and intelligent robotics.For a hydrogel strain sensor,certain challenges need to be urgently addressed for practical applications,such as the damage caused by external effects,leading to equipment failure,and the inability to perceive ambient temperature,resulting in single functionality.Herein,a stretchable,self-healing and dual temperature-strain sensitive hydrogel,with a physically-crosslinked network,is designed by constructing multiple dynamic reversible bonds.Graphene oxide(GO)and iron ions(Fe^(3+))act as dynamic bridges in the cross-linked network and are mediated by the covalent and hydrogen bonding,rendering excellent stretchability to the hydrogel.The reversible features of coordination interactions and hydrogen interactions endow excellent recoverability and self-healing properties.Moreover,the incorporated N-isopropyl acrylamide(NIPAM)provides excellent temperature responsiveness to the hydrogel,facilitating the detection of external temperature changes.Meanwhile,the hydrogels exhibited strain-sensitivity,with a wide working range of 1%-300%,fast response and electrical stability,which can be used as flexible sensors to monitor body motions,e.g.,speaking and the bending of finger,wrist,elbow and knee.Overall,the hydrogel possesses dual sensory capabilities,combining external temperature and strain,for potential applications in wearable multifunctional sensing devices.
基金the funding and generous support of the National Natural Science Foundation of China(52103263,52271249)the Key Project of International Science&Technology Cooperation of Shaanxi Province(2023-GHZD-09)+5 种基金the Key Project of Science Foundation of Education Department of Shaanxi Province(22JY011)the Key Project of Scientific Research and Development of Shaanxi Province(2023GXLH-070)the Qinchuangyuan"Scientist+Engineer"Team of Shaanxi Province(2023KXJ-069)the Key Research and Development Program of Shaanxi(2023-YBGY-488)the Sci-tech Innovation Team of Shaanxi Province(2024RS-CXTD-46)the Key Research and Development Program of Shaanxi Province(2020ZDLGY13-11).
文摘All-season thermal management with zero energy consumption and emissions is more crucial to global decarbonization over traditional energy-intensive cooling/heating systems.However,the static single thermal management for cooling or heating fails to self-regulate the temperature in dynamic seasonal temperature condition.Herein,inspired by the dual-temperature regulation function of the fur color changes on the backs and abdomens of penguins,a smart thermal management composite hydrogel(PNA@H-PM Gel)system was subtly created though an"on-demand"dual-layer structure design strategy.The PNA@H-PM Gel system features synchronous solar and thermal radiation modulation as well as tunable phase transition temperatures to meet the variable seasonal thermal requirements and energy-saving demands via self-adaptive radiative cooling and solar heating regulation.Furthermore,this system demonstrates superb modulations of both the solar reflectance(ΔR=0.74)and thermal emissivity(ΔE=0.52)in response to ambient temperature changes,highlighting efficient temperature regulation with average radiative cooling and solar heating effects of 9.6℃in summer and 6.1℃in winter,respectively.Moreover,compared to standard building baselines,the PNA@H-PM Gel presents a more substantial energy-saving cooling/heating potentials for energy-efficient buildings across various regions and climates.This novel solution,inspired by penguins in the real world,will offer a fresh approach for producing intelligent,energy-saving thermal management materials,and serve for temperature regulation under dynamic climate conditions and even throughout all seasons.
基金the National Natural Science Foundation of China (No. 20276065).
文摘Temperature-sensitive hydrogel—poly(N-isopropyl acrylamide) (PNIPA) was prepared and applied to protein refolding. PNIPA gel disks and gel particles were synthesized by the solution polymerization and inverse suspension polymerization respectively. The swelling kinetics of the gels was also studied. With these prepared PNIPA gels, the model protein lysozyme was renatured. Within 24h, PNIPA gel disks improved the yield of lysozyme activity by 49.3% from 3375.2U·mg^-1 to 5038.8U·mg^-1. With the addition of faster response PNIPA gel beads, the total lysozyme activity recovery was about 68.98% in 3h, as compared with 42.03% by simple batch dilution. The novel refolding system with PNIPA enables efficient refolding especially at high protein concentrations. Discussion about the mechanism revealed that when PNIPA gels were added into the refolding buffer, the hydrophobic interactions between denatured proteins and polymer gels could prevent the aggregation of refolding intermediates, thus enhanced the protein renaturation.
基金supported by the National Natural Science Foundation of China(52475610)Zhejiang Provincial Natural Science Foundation of China(LDQ24E050001).
文摘Despite the promising progress in conductive hydrogels made with pure conducting polymer,great challenges remain in the interface adhesion and robustness in longterm monitoring.To address these challenges,Prof.Seung Hwan Ko and Taek-Soo Kim’s team introduced a laserinduced phase separation and adhesion method for fabricating conductive hydrogels consisting of pure poly(3,4-ethylenedioxythiophene):polystyrene sulfonate on polymer substrates.The laser-induced phase separation and adhesion treated conducting polymers can be selectively transformed into conductive hydrogels that exhibit wet conductivities of 101.4 S cm^(−1) with a spatial resolution down to 5μm.Moreover,they maintain impedance and charge-storage capacity even after 1 h of sonication.The micropatterned electrode arrays demonstrate their potential in long-term in vivo signal recordings,highlighting their promising role in the field of bioelectronics.
文摘The swelling behavior of a temperature-sensitive poly-N-isopropylacrylamide(PNIPAM) hydrogel circular cylinder is studied subjected to combined extension-torsion and varied temperature. In this regard, a semi-analytical solution is proposed for general combined loading. A finite element(FE) analysis is conducted, subjecting a hydrogel cylinder to the combined extension-torsion and the varied temperature to evaluate the validity and accuracy of the solution. A user-defined UHYPER subroutine is developed and verified under free and constrained swelling conditions. The FE results illustrate excellent agreement with the semi-analytical solution. Due to the complexity of the problem, some compositions and applied loading factors are analyzed. It is revealed that for larger cross-linked density and larger ending temperature, the cylinder yields higher stresses and smaller radial swelling deformation. Besides, the radial and hoop stresses increase by applying larger twist and axial stretch. The hoop stresses intersect at approximately R/Rout = 0.58, where the hoop stress vanishes. Besides, the axial force has direct and inverse relationships with the axial stretch and the twist, respectively. However, the resultant torsional moment behavior is complex, and the position of the maximum point varies significantly by altering the axial stretch and the twist.
文摘Hydrogels, as a novel class of biomaterials, exhibit broad application prospects and are widely used in tissue engineering. In the field of periodontology within dental medicine, hydrogels can be employed for periodontal tissue regeneration to repair the damage caused by periodontitis. At present, various hydrogels have been developed to control periodontal inflammation and repair periodontal tissues. This article, based on domestic and international literature, provides a brief review of hydrogels used in periodontal tissue regeneration.
基金financially supported by the National Natural Science Foundation of China(Nos.52273009 and 21674037).
文摘Insulin is an essential and versatile protein taking part in the control of blood glucose levels and protein anabolism.However,under prolonged storage or high temperature stress,insulin tends to unfold and aggregate into toxic amyloid fibrils,leading to loss of physiological function.Inspired by natural chaperones,a series of temperature-sensitive polycaprolactone-based micelles were designed to prevent insulin from deactivation.The micelles were fabricated through the self-assembly of amphiphilic copolymers of methoxy poly(ethylene glycol)-poly(4-diethylformamide caprolactone-co-caprolactone)(mPEG_(17)-P(DECL-co-CL)),which had a regular spherical morphology with particle sizes of about 100 nm.In addition,the lower critical solution temperature(LCST)of the micelles could be tuned to 9 and 29℃by changing the ratio of DECL to CL.Benefiting from the temperature-sensitivity of DECL segment,the binding ability of micelles to insulin could be modulated by changing the temperature.Above LCST,micelles effectively inhibited insulin aggregation and protected it from thermal inactivation due to the strong binding ability between the hydrophobic segment DECL and insulin.Below LCST,DECL segment returned to hydrophilic and bound weakly with insulin,leading to the release of insulin and assisting in its recovery of secondary structure.Thus,these temperature-sensitive micelles provided an effective strategy for insulin protection.
基金the Ministry of Human Resource and Development (MHRD) Government of India for funding
文摘In the current transformative era of biomedicine,hydrogels have established their presence in biomaterials due to their superior biocompatibility,tuneability and resemblance with native tissue.However,hydrogels typically exhibit poor conductivity due to their hydrophilic polymer structure.Electrical conductivity provides an important enhancement to the properties of hydrogel-based systems in various biomedical applications such as drug delivery and tissue engineering.Consequently,researchers are developing combinatorial strategies to develop electrically responsive“SMART”systems to improve the therapeutic efficacy of biomolecules.Electrically conductive hydrogels have been explored for various drug delivery applications,enabling higher loading of therapeutic cargo with on-demand delivery.This review emphasizes the properties,mechanisms,fabrication techniques and recent advancements of electrically responsive“SMART”systems aiding on-site drug delivery applications.Additionally,it covers prospects for the successful translation of these systems into clinical research.
基金supported by the Smart Medicine and Engineering Interdisciplinary Innovation Project of Ningbo University(Grant No.ZHYG003)the National Natural Science Foundation of China(Grant Nos.12372165 and 12202387)+1 种基金the Ningbo Top Medical and Health Research Program(Grant No.2022020203)the Zhejiang Engineering Research Center of Innovative technologies and diagnostic and thera-peutic equipment for urinary system diseases.
文摘Enhancing gelatin methacryloyl(GelMA)hydrogel mechanics without compromising biocompatibility remains challenging,as conventional chemical crosslinking often disrupts degradation behavior.A cooling-induced entan-glement strategy effectively improves mechanical performance while preserving biological properties;however,its underlying mechanisms remain unclear.This study demonstrates that extended cooling durations significantly enhance the mechanical properties of GelMA hydrogels.Microstructural analyses reveal cooling-induced forma-tion of compact polymer networks with reduced mesh sizes.Molecular dynamics(MD)simulations confirm that the cooling process promotes topological entanglements that govern mechanical reinforcement.Guided by these insights,we propose a theoretical model to predict the stress responses of GelMA hydrogels under various cooling durations,establishing quantitative correlations between entanglement mechanisms and mechanical outcomes.This study provides a fundamental understanding of the interplay between cooling conditions,microstructure,and mechanical performance,offering a robust framework for designing GelMA hydrogels with optimized me-chanical properties for advanced biomedical applications.
基金financially supported by the National Key Research and Development Program of China(2022YFE0138900)the National Natural Science Foundation of China(21972017)+1 种基金the Fundamental Research Funds for the Central Universities of Ministry of Education of China(D5000240188)the"Scientific and Technical Innovation Action Plan"Basic Research Field of Shanghai Science and Technology Committee(19JC1410500)。
文摘Traditional hydrogels are inevitably damaged during practical applications,resulting in a gradual deterioration of their functional efficacy.A primary strategy to address this issue involves developing hydrogels with inherent self-healing properties.In this study,we report the synthesis of self-healing polyacrylate hydrogels that integrate zwitterions,hydrophilic nano-silica and aluminum ions.Due to the synergistic effect of multiple hydrogen bonds,coordination bonds and electrostatic interactions,the tensile strength of the hydrogel is enhanced from 15.1 to 162.6 kPa.Moreover,the electrical resistance and tensile strength of the hydrogel can almost recover to its initial values after 20 min of healing at room temperature,exhibiting remarkable self-healing performance.Furthermore,the zwitterionic polyacrylate hydrogel serves as a wearable sensor with the capability of accurately response to the bending and stretching of human joints,exhibting a gauge factor of 1.87 under tensile strain ranging from 80% to 100%.Even after being freezed at-20℃ for 3 h,the zwitterionic polyacrylate hydrogel retains its exceptional writing performance.In conclusion,the hydrogels developed in this study demonstrate significant potential for wearable electronics applications.
