The root system actively reacts to mechanical stimuli in its environment,transmitting mechanical signals to optimize the utilization of environmental resources.While the mechanical impedance created by the growth medi...The root system actively reacts to mechanical stimuli in its environment,transmitting mechanical signals to optimize the utilization of environmental resources.While the mechanical impedance created by the growth medium serves as the primary source of stimulation for the roots,extensive research has focused on the roots'response to static mechanical stimulation.However,the impact of dynamic mechanical stimulation on root phenotype remains underexplored.In this study,we utilized a low acyl gellan gum/polyacrylamide(GG/PAM)double network elastic hydrogel as the growth medium for rapeseed.We constructed a mechanical device to investigate the effects of reciprocating extrusion stimulation on the growth of the rapeseed root system.After three weeks of mechanical stimulation,the root system exhibited a significant increase in lateral roots.This branching enhanced the roots'anchoring and penetration into the hydrogel,thereby improving the root system's adaptability to its environment.Our findings offer valuable data and insights into the effects of reciprocating mechanical stimulation on root growth,providing a new way for engineering root phenotype.展开更多
Infectious bone defects represent a substantial challenge in clinical practice,necessitating the deployment of advanced therapeutic strategies.This study presents a treatment modality that merges a mild photothermal t...Infectious bone defects represent a substantial challenge in clinical practice,necessitating the deployment of advanced therapeutic strategies.This study presents a treatment modality that merges a mild photothermal therapy hydrogel with a pulsed drug delivery mechanism.The system is predicated on a hydrogel matrix that is thermally responsive,characteristic of bone defect sites,facilitating controlled and site-specific drug release.The cornerstone of this system is the incorporation of mild photothermal nanoparticles,which are activated within the temperature range of 40–43°C,thereby enhancing the precision and efficacy of drug delivery.Our findings demonstrate that the photothermal response significantly augments the localized delivery of therapeutic agents,mitigating systemic side effects and bolstering efficacy at the defect site.The synchronized pulsed release,cooperated with mild photothermal therapy,effectively addresses infection control,and promotes bone regeneration.This approach signifies a considerable advancement in the management of infectious bone defects,offering an effective and patient-centric alternative to traditional methods.Our research endeavors to extend its applicability to a wider spectrum of tissue regeneration scenarios,underscoring its transformative potential in the realm of regenerative medicine.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
Stimuli-responsive shape-changing materials,particularly hydrogel and liquid crystal elastomer(LCE),have demonstrated significant potential for applications across various fields.Although intricate deformation and act...Stimuli-responsive shape-changing materials,particularly hydrogel and liquid crystal elastomer(LCE),have demonstrated significant potential for applications across various fields.Although intricate deformation and actuation behaviors have been obtained in either hydrogels or LCEs,they typically undergo reversible shape change only once(e.g.,one expansion plus one contraction)during one heating/cooling cycle.Herein,we report a study of a novel liquid crystalline hydrogel(LCH)and the achievement of dual actuation in a single heating/cooling cycle by integrating the characteristics of thermoresponsive hydrogel and LCE.The dual actuation behavior arises from the reversible volume phase transition of poly(N-isopropylacrylamide)(PNIPAM)and the reversible order-disorder phase transition of LC mesogens in the LCH.Due to a temperature window separating the two transitions belonging to PNIPAM and LCE,LCH actuator can sequentially execute their respective actuation,thus deforming reversibly twice,during a heating/cooling cycle.The relative actuation degree of the two mechanisms is influenced by the mass ratio of PNIPAM to LCE in the LCH.Moreover,the initial shape of a bilayer actuator made with an active LCH layer and a passive polymer layer can be altered through hydration or dehydration of PNIPAM,which further modifies the dual actuation induced deformation.This work provides an example that shows the interest of developing LCH actuators.展开更多
Silver nanoparticles(Ag NPs)have attracted attention in the field of biomaterials due to their excellent antibacterial property.However,the reducing and stabilizing agents used for the chemical reduction of Ag NPs are...Silver nanoparticles(Ag NPs)have attracted attention in the field of biomaterials due to their excellent antibacterial property.However,the reducing and stabilizing agents used for the chemical reduction of Ag NPs are usually toxic and may cause water pollution.In this work,Ag NPs(31.2 nm in diameter)were prepared using the extract of straw,an agricultural waste,as the reducing and stabilizing agent.Experimental analysis revealed that the straw extract contained lignin,the structure of which possesses phenolic hydroxyl and methoxy groups that facilitate the reduction of silver salts into Ag NPs.The surfaces of Ag NPs were negatively charged due to the encapsulation of a thin layer of lignin molecules that prevented their aggregation.After the prepared Ag NPs were added to the precursor solution of acrylamide,free radical polymerization was triggered without the need for extra heating or light irradiation,resulting in the rapid formation of an Ag NP-polyacrylamide composite hydrogel.The inhibition zone test proved that the composite hydrogel possessed excellent antibacterial ability due to the presence of Ag NPs.The prepared hydrogel may have potential applications in the fabrication of biomedical materials,such as antibacterial dressings.展开更多
Smart farming with outdoor monitoring systems is critical to address food shortages and sustainability challenges.These systems facilitate informed decisions that enhance efficiency in broader environmental management...Smart farming with outdoor monitoring systems is critical to address food shortages and sustainability challenges.These systems facilitate informed decisions that enhance efficiency in broader environmental management.Existing outdoor systems equipped with energy harvesters and self-powered sensors often struggle with fluctuating energy sources,low durability under harsh conditions,non-transparent or non-biocompatible materials,and complex structures.Herein,a multifunctional hydrogel is developed,which can fulfill all the above requirements and build selfsustainable outdoor monitoring systems solely by it.It can serve as a stable energy harvester that continuously generates direct current output with an average power density of 1.9 W m^(-3)for nearly 60 days of operation in normal environments(24℃,60%RH),with an energy density of around 1.36×10^(7)J m^(-3).It also shows good self-recoverability in severe environments(45℃,30%RH)in nearly 40 days of continuous operation.Moreover,this hydrogel enables noninvasive and self-powered monitoring of leaf relative water content,providing critical data on evaluating plant health,previously obtainable only through invasive or high-power consumption methods.Its potential extends to acting as other self-powered environmental sensors.This multifunctional hydrogel enables self-sustainable outdoor systems with scalable and low-cost production,paving the way for future agriculture.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
Rechargeable zinc(Zn)-ion batteries(RZIBs) with hydrogel electrolytes(HEs) have gained significant attention in the last decade owing to their high safety, low cost, sufficient material abundance, and superb environme...Rechargeable zinc(Zn)-ion batteries(RZIBs) with hydrogel electrolytes(HEs) have gained significant attention in the last decade owing to their high safety, low cost, sufficient material abundance, and superb environmental friendliness, which is extremely important for wearable energy storage applications. Given that HEs play a critical role in building flexible RZIBs, it is urgent to summarize the recent advances in this field and elucidate the design principles of HEs for practical applications. This review systematically presents the development history, recent advances in the material fundamentals, functional designs, challenges, and prospects of the HEs-based RZIBs. Firstly, the fundamentals, species, and flexible mechanisms of HEs are discussed, along with their compatibility with Zn anodes and various cathodes. Then, the functional designs of hydrogel electrolytes in harsh conditions are comprehensively discussed, including high/low/wide-temperature windows, mechanical deformations(e.g., bending, twisting, and straining), and damages(e.g., cutting, burning, and soaking). Finally, the remaining challenges and future perspectives for advancing HEs-based RZIBs are outlined.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
Bioactive molecules have shown great promise for effectively regulating various bone formation processes,rendering them attractive therapeutics for bone regeneration.However,the widespread application of bioactive mol...Bioactive molecules have shown great promise for effectively regulating various bone formation processes,rendering them attractive therapeutics for bone regeneration.However,the widespread application of bioactive molecules is limited by their low accumulation and short half-lives in vivo.Hydrogels have emerged as ideal carriers to address these challenges,offering the potential to prolong retention times at lesion sites,extend half-lives in vivo and mitigate side effects,avoid burst release,and promote adsorption under physiological conditions.This review systematically summarizes the recent advances in the development of bioactive molecule-loaded hydrogels for bone regeneration,encompassing applications in cranial defect repair,femoral defect repair,periodontal bone regeneration,and bone regeneration with underlying diseases.Additionally,this review discusses the current strategies aimed at improving the release profiles of bioactive molecules through stimuli-responsive delivery,carrier-assisted delivery,and sequential delivery.Finally,this review elucidates the existing challenges and future directions of hydrogel encapsulated bioactive molecules in the field of bone regeneration.展开更多
Hydrogel scaffolds have numerous potential applications in the tissue engineering field.However,tough hydrogel scaffolds implanted in vivo are seldom reported because it is difficult to balance biocompatibility and hi...Hydrogel scaffolds have numerous potential applications in the tissue engineering field.However,tough hydrogel scaffolds implanted in vivo are seldom reported because it is difficult to balance biocompatibility and high mechanical properties.Inspired by Chinese ramen,we propose a universal fabricating method(printing-P,training-T,cross-linking-C,PTC&PCT)for tough hydrogel scaffolds to fill this gap.First,3D printing fabricates a hydrogel scaffold with desired structures(P).Then,the scaffold could have extraordinarily high mechanical properties and functional surface structure by cycle mechanical training with salting-out assistance(T).Finally,the training results are fixed by photo-cross-linking processing(C).The tough gelatin hydrogel scaffolds exhibit excellent tensile strength of 6.66 MPa(622-fold untreated)and have excellent biocompatibility.Furthermore,this scaffold possesses functional surface structures from nanometer to micron to millimeter,which can efficiently induce directional cell growth.Interestingly,this strategy can produce bionic human tissue with mechanical properties of 10 kPa-10 MPa by changing the type of salt,and many hydrogels,such as gelatin and silk,could be improved with PTC or PCT strategies.Animal experiments show that this scaffold can effectively promote the new generation of muscle fibers,blood vessels,and nerves within 4 weeks,prompting the rapid regeneration of large-volume muscle loss injuries.展开更多
Vascular endothelial growth factor and its mimic peptide KLTWQELYQLKYKGI(QK)are widely used as the most potent angiogenic factors for the treatment of multiple ischemic diseases.However,conventional topical drug deliv...Vascular endothelial growth factor and its mimic peptide KLTWQELYQLKYKGI(QK)are widely used as the most potent angiogenic factors for the treatment of multiple ischemic diseases.However,conventional topical drug delivery often results in a burst release of the drug,leading to transient retention(inefficacy)and undesirable diffusion(toxicity)in vivo.Therefore,a drug delivery system that responds to changes in the microenvironment of tissue regeneration and controls vascular endothelial growth factor release is crucial to improve the treatment of ischemic stroke.Matrix metalloproteinase-2(MMP-2)is gradually upregulated after cerebral ischemia.Herein,vascular endothelial growth factor mimic peptide QK was self-assembled with MMP-2-cleaved peptide PLGLAG(TIMP)and customizable peptide amphiphilic(PA)molecules to construct nanofiber hydrogel PA-TIMP-QK.PA-TIMP-QK was found to control the delivery of QK by MMP-2 upregulation after cerebral ischemia/reperfusion and had a similar biological activity with vascular endothelial growth factor in vitro.The results indicated that PA-TIMP-QK promoted neuronal survival,restored local blood circulation,reduced blood-brain barrier permeability,and restored motor function.These findings suggest that the self-assembling nanofiber hydrogel PA-TIMP-QK may provide an intelligent drug delivery system that responds to the microenvironment and promotes regeneration and repair after cerebral ischemia/reperfusion injury.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
Bionic hydrogels offer significant advantages over conventional counterparts,boasting superior properties like enhanced adhesion,stretchability,conductivity,biocompatibility and versatile functionalities.Their physico...Bionic hydrogels offer significant advantages over conventional counterparts,boasting superior properties like enhanced adhesion,stretchability,conductivity,biocompatibility and versatile functionalities.Their physicochemical resemblance to biological tissues makes bionic hydrogels ideal interfaces for bioelectronic devices.In contrast,conventional hydrogels often exhibit inadequate performance,such as easy detachment,lack of good skin compliance,and inadequate conductivity,failing to meet the rigorous demands of bioelectronic applications.Bionic hydrogels,inspired by biological designs,exhibit exceptional physicochemical characteristics that fulfill diverse criteria for bioelectronic applications,driving the advancement of bioelectronic devices.This review first introduces a variety of materials used in the fabrication of bionic hydrogels,including natural polymers,synthetic polymers,and other materials.Then different mechanisms of hydrogel bionics,are categorized into material bionics,structural bionics,and functional bionics based on their bionic approaches.Subsequently,various applications of bionic hydrogels in the field of bioelectronics were introduced,including physiological signal monitoring,tissue engineering,and human-machine interactions.Lastly,the current development and future prospects of bionic hydrogels in bioelectronic devices are summarized.Hopefully,this comprehensive review could inspire advancements in bionic hydrogels for applications in bioelectronic devices.展开更多
The management of chronic wounds remains a substantial challenge for healthcare providers. Inadequate wound care can result in serious complications, including infection, which may ultimately lead to amputation or eve...The management of chronic wounds remains a substantial challenge for healthcare providers. Inadequate wound care can result in serious complications, including infection, which may ultimately lead to amputation or even death. While traditional excipients exhibit some efficacy in promoting wound healing, they are not sufficiently effective in preventing wound infections. As an antimicrobial metal, copper has a long history in the antimicrobial field, and at the same time, wound auxiliaries with copper ions have also been used in the treatment of chronic wounds. To address the limitations of conventional wound dressings, including insufficient antimicrobial properties and limited capacity to promote wound healing, this study introduces a highly adhesive hydrogel with superior mechanical stability for non-invasive wound treatment. The hydrogel was composed of carboxymethyl chitosan, tannic acid and copper ions. The tannic acid solution was subjected to dropwise addition of CuCl2 solution to produce precipitation, and tannic acid/copper ions (TA/Cu2+) composite nanoparticles were prepared. Through topological adhesion, the CMCS with pH sensitivity has the ability to establish adhesive connections with a wide range of materials. The benefits of CMCS/TA/Cu2+ hydrogel, as a kind of wound closure and repair material, include efficient wound closure, and resistance against bacterial invasion while maintaining cleanliness. Additionally, it exhibits excellent tensile and mechanical stability that can facilitate effective closure and repair in dynamic areas like joint wounds. This promising hydrogel adhesive has demonstrated potential as a material for wound closure and restoration.展开更多
Due to their high water content,stimulus responsiveness,and biocompatibility,hydrogels,which are functional materials with a three-dimensional network structure,are widely applied in fields such as biomedicine,environ...Due to their high water content,stimulus responsiveness,and biocompatibility,hydrogels,which are functional materials with a three-dimensional network structure,are widely applied in fields such as biomedicine,environmental monitoring,and flexible electronics.This paper provides a systematic review of hydrogel charac-terization methods and their applications,focusing on primary evaluation techniques for physical properties(e.g.,mechanical strength,swelling behavior,and pore structure),chemical properties(e.g.,composition,crosslink density,and degradation behavior),biocompatibility,and functional properties(e.g.,drug release,environmental stimulus response,and conductivity).It analyzes the challenges currently faced by characterization methods,such as a lack of standardization,difficulties in dynamic monitoring,an insufficient micro-macro correlation,and poor adaptability to complex environments.It proposes solutions,such as a hierarchical standardization system,in situ imaging technology,cross-scale characterization,and biomimetic testing platforms.Looking ahead,hydrogel characterization techniques will evolve toward intelligent,real-time,multimodal coupling and standardized approaches.These techniques will provide superior technical support for precision medicine,environmental restoration,and flexible electronics.They will also offer systematic methodological guidance for the performance optimization and practical application of hydrogel materials.展开更多
Polyvinyl alcohol(PVA)hydrogels doped with cyclohexane-1,2,3,4,5,6-hexacarboxylic acid(CHA)were successfully prepared during drying and swelling.Structural and morphological characterizations suggest the carboxyl and ...Polyvinyl alcohol(PVA)hydrogels doped with cyclohexane-1,2,3,4,5,6-hexacarboxylic acid(CHA)were successfully prepared during drying and swelling.Structural and morphological characterizations suggest the carboxyl and hydroxyl groups in the material undergo esterification during the preparation of the material,which contributes to the high transparency with 90%transmittance in the 400 to 800 nm range and robust mechanical properties of the material with a tensile strength at a break of 27.55 MPa.It is noteworthy that the bending and torsion angles exhibit a strong linear correlation with electrical resistance,enabling the monitoring of the bending motion state of each human body segment.展开更多
Repairing and regenerating cartilage defects in osteoarthritis patients remains challenging.Traditional treatments primarily offer symptom relief without addressing the underlying progression of the disease.Stem cell ...Repairing and regenerating cartilage defects in osteoarthritis patients remains challenging.Traditional treatments primarily offer symptom relief without addressing the underlying progression of the disease.Stem cell therapies provide a promising solution,yet they face limitations such as short retention times,low survival rates in vivo,and insufficient extracellular matrix(ECM)production.Stem cell-based hydrogel therapy offers a controlled microenvironment that can mitigate these challenges and enhance cell therapy effectiveness.This review evaluates the advantages and limitations of various stem cell types and hydrogel materials,summarizing recent advances in their combination for cartilage repair.The potential of stem cell-hydrogel therapies is highlighted,along with the remaining challenges and future directions for improving their clinical application.展开更多
Hydrogel has developed into a very important platform in solar interface evaporator.However,the current hydrogel evaporators are usually three-dimensional evaporators,which will consume a lot of raw materials.Thus,a n...Hydrogel has developed into a very important platform in solar interface evaporator.However,the current hydrogel evaporators are usually three-dimensional evaporators,which will consume a lot of raw materials.Thus,a new two-dimensional hydrogel evaporator is urgently needed to alleviate this problem.Here,a double layer hydrogel evaporator was designed by twice vacuum filtration.Furthermore,through the arched design and the introduction of concentrated brine drainage system,the hydrogel evaporator has enhanced water transportation and tailored water transportation path.Such a unique drainage evaporation system greatly improves the stability of the evaporator.Thereby,a good balance is established between photothermal conversion and water supply,and solar energy is utilized efficiently.It can remain stable in continuous evaporation for up to 12 h with an excellent evaporation rate of 2.70 kg m^(-2)h^(-1)under 1 sun irradiation.Meanwhile,the drainage system realized the 1.8×10^(-10)mol m^(-2)s^(-1)diffusion flux of concentrated brine.Through one-time freeze-drying preparation,an arch-shaped drainage evaporator was used to prepare an evaporation area of more than 20 cm^(2).With the self-made condensate collecting device in outdoor environment,the fresh water yield reaches 7.5 L m^(-2)d^(-1).This provides a new scheme for building a new hydrogel evaporator and solving the fresh water crisis.展开更多
Pacinian Corpuscle(PC)is the largest tactile vibration receptor in mammalian skin,with a layered structure that enables signal amplification and high-pass filtering functions.Modern robots feature vibro-tactile sensor...Pacinian Corpuscle(PC)is the largest tactile vibration receptor in mammalian skin,with a layered structure that enables signal amplification and high-pass filtering functions.Modern robots feature vibro-tactile sensors with excellent mechanical properties and fine resolution,but these sensors are prone to low-frequency noise interference when detecting high-frequency vibrations.In this study,a bionic PC with a longitudinally decreasing dynamic fractal structure is proposed.By creating a lumped parameter model of the PC’s layered structure,the bionic PC made of gelatin-chitosan based hydrogel can achieve high-pass filtering and specific frequency band signal amplification without requiring back-end circuits.The experimental results demonstrate that the bionic PC retains the structural characteristics of a natural PC,and the influence of structural factors,such as the number of layers in its shell,on filtration characteristics is explored.Additionally,a vibration source positioning experiment was conducted to simulate the earthquake sensing abilities of elephants.This natural structural design simplifies the filter circuit,is low-cost,cost-effective,stable in performance,and reduces redundancy in the robot’s signal circuit.Integrating this technology with robots can enhance their environmental perception,thereby improving the safety of interactions.展开更多
基金supporting from Shanghai Pujiang Program(23PJ1400400)DHU startup grant,the Fundamental Research Funds for the Central Universities,DHU Distinguished Young Professor Program.
文摘The root system actively reacts to mechanical stimuli in its environment,transmitting mechanical signals to optimize the utilization of environmental resources.While the mechanical impedance created by the growth medium serves as the primary source of stimulation for the roots,extensive research has focused on the roots'response to static mechanical stimulation.However,the impact of dynamic mechanical stimulation on root phenotype remains underexplored.In this study,we utilized a low acyl gellan gum/polyacrylamide(GG/PAM)double network elastic hydrogel as the growth medium for rapeseed.We constructed a mechanical device to investigate the effects of reciprocating extrusion stimulation on the growth of the rapeseed root system.After three weeks of mechanical stimulation,the root system exhibited a significant increase in lateral roots.This branching enhanced the roots'anchoring and penetration into the hydrogel,thereby improving the root system's adaptability to its environment.Our findings offer valuable data and insights into the effects of reciprocating mechanical stimulation on root growth,providing a new way for engineering root phenotype.
基金supported by the National Natural Science Foundation of China(32171354,82222015,82171001)The National Key Research and Development Program of China2023YFC2413600Research Funding from West China School/Hospital of Stomatology,Sichuan University(No.RCDWIS2023-1).
文摘Infectious bone defects represent a substantial challenge in clinical practice,necessitating the deployment of advanced therapeutic strategies.This study presents a treatment modality that merges a mild photothermal therapy hydrogel with a pulsed drug delivery mechanism.The system is predicated on a hydrogel matrix that is thermally responsive,characteristic of bone defect sites,facilitating controlled and site-specific drug release.The cornerstone of this system is the incorporation of mild photothermal nanoparticles,which are activated within the temperature range of 40–43°C,thereby enhancing the precision and efficacy of drug delivery.Our findings demonstrate that the photothermal response significantly augments the localized delivery of therapeutic agents,mitigating systemic side effects and bolstering efficacy at the defect site.The synchronized pulsed release,cooperated with mild photothermal therapy,effectively addresses infection control,and promotes bone regeneration.This approach signifies a considerable advancement in the management of infectious bone defects,offering an effective and patient-centric alternative to traditional methods.Our research endeavors to extend its applicability to a wider spectrum of tissue regeneration scenarios,underscoring its transformative potential in the realm of regenerative medicine.
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financial support from the Natural Sciences and Engineering Research Council of Canada(NSERC),le Fonds de recherche du Québec:Nature et technologies(FRQNT),and The Centre québécois sur les matériaux fonctionnels.
文摘Stimuli-responsive shape-changing materials,particularly hydrogel and liquid crystal elastomer(LCE),have demonstrated significant potential for applications across various fields.Although intricate deformation and actuation behaviors have been obtained in either hydrogels or LCEs,they typically undergo reversible shape change only once(e.g.,one expansion plus one contraction)during one heating/cooling cycle.Herein,we report a study of a novel liquid crystalline hydrogel(LCH)and the achievement of dual actuation in a single heating/cooling cycle by integrating the characteristics of thermoresponsive hydrogel and LCE.The dual actuation behavior arises from the reversible volume phase transition of poly(N-isopropylacrylamide)(PNIPAM)and the reversible order-disorder phase transition of LC mesogens in the LCH.Due to a temperature window separating the two transitions belonging to PNIPAM and LCE,LCH actuator can sequentially execute their respective actuation,thus deforming reversibly twice,during a heating/cooling cycle.The relative actuation degree of the two mechanisms is influenced by the mass ratio of PNIPAM to LCE in the LCH.Moreover,the initial shape of a bilayer actuator made with an active LCH layer and a passive polymer layer can be altered through hydration or dehydration of PNIPAM,which further modifies the dual actuation induced deformation.This work provides an example that shows the interest of developing LCH actuators.
基金financially supported by the National Natural Science Foundation of China(No.52203209)the State Key Laboratory of Solid Waste Reuse for Building Materials,China(No.SWR-2022-009)the Fundamental Research Funds for the Central Universities,China(No.FRF-IDRY22-012)。
文摘Silver nanoparticles(Ag NPs)have attracted attention in the field of biomaterials due to their excellent antibacterial property.However,the reducing and stabilizing agents used for the chemical reduction of Ag NPs are usually toxic and may cause water pollution.In this work,Ag NPs(31.2 nm in diameter)were prepared using the extract of straw,an agricultural waste,as the reducing and stabilizing agent.Experimental analysis revealed that the straw extract contained lignin,the structure of which possesses phenolic hydroxyl and methoxy groups that facilitate the reduction of silver salts into Ag NPs.The surfaces of Ag NPs were negatively charged due to the encapsulation of a thin layer of lignin molecules that prevented their aggregation.After the prepared Ag NPs were added to the precursor solution of acrylamide,free radical polymerization was triggered without the need for extra heating or light irradiation,resulting in the rapid formation of an Ag NP-polyacrylamide composite hydrogel.The inhibition zone test proved that the composite hydrogel possessed excellent antibacterial ability due to the presence of Ag NPs.The prepared hydrogel may have potential applications in the fabrication of biomedical materials,such as antibacterial dressings.
基金supported by the Research Platform for biomedical and Health Technology, NUS (Suzhou) Research Institute (RP-BHT-Prof. LEE Chengkuo)RIE Advanced Manufacturing and Engineering (AME) Programmatic Grant (Grant A18A4b0055)+1 种基金RIE 2025-Industry Alignment Fund – Industry Collaboration Projects (IAF-ICP) (Grant I2301E0027)Reimagine Research Scheme projects, National University of Singapore, A-0009037-03-00 and A-0009454-01-00 and Reimagine Research Scheme projects, National University of Singapore, A-0004772-00-00 and A-0004772-01-00。
文摘Smart farming with outdoor monitoring systems is critical to address food shortages and sustainability challenges.These systems facilitate informed decisions that enhance efficiency in broader environmental management.Existing outdoor systems equipped with energy harvesters and self-powered sensors often struggle with fluctuating energy sources,low durability under harsh conditions,non-transparent or non-biocompatible materials,and complex structures.Herein,a multifunctional hydrogel is developed,which can fulfill all the above requirements and build selfsustainable outdoor monitoring systems solely by it.It can serve as a stable energy harvester that continuously generates direct current output with an average power density of 1.9 W m^(-3)for nearly 60 days of operation in normal environments(24℃,60%RH),with an energy density of around 1.36×10^(7)J m^(-3).It also shows good self-recoverability in severe environments(45℃,30%RH)in nearly 40 days of continuous operation.Moreover,this hydrogel enables noninvasive and self-powered monitoring of leaf relative water content,providing critical data on evaluating plant health,previously obtainable only through invasive or high-power consumption methods.Its potential extends to acting as other self-powered environmental sensors.This multifunctional hydrogel enables self-sustainable outdoor systems with scalable and low-cost production,paving the way for future agriculture.
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supported by the National Natural Science Foundation of China (22379038)Science Research Project of Hebei Education Department (JZX2024015)+4 种基金Shijiazhuang Science and Technology Plan Project (241791357A)Central Guidance for Local Science and Technology Development Funds Project (246Z4408G)Excellent Youth Research Innovation Team of Hebei University (QNTD202410)High-level Talents Research Start-Up Project of Hebei University (521100224223)Hebei Province Innovation Capability Enhancement Plan Project (22567620H)。
文摘Rechargeable zinc(Zn)-ion batteries(RZIBs) with hydrogel electrolytes(HEs) have gained significant attention in the last decade owing to their high safety, low cost, sufficient material abundance, and superb environmental friendliness, which is extremely important for wearable energy storage applications. Given that HEs play a critical role in building flexible RZIBs, it is urgent to summarize the recent advances in this field and elucidate the design principles of HEs for practical applications. This review systematically presents the development history, recent advances in the material fundamentals, functional designs, challenges, and prospects of the HEs-based RZIBs. Firstly, the fundamentals, species, and flexible mechanisms of HEs are discussed, along with their compatibility with Zn anodes and various cathodes. Then, the functional designs of hydrogel electrolytes in harsh conditions are comprehensively discussed, including high/low/wide-temperature windows, mechanical deformations(e.g., bending, twisting, and straining), and damages(e.g., cutting, burning, and soaking). Finally, the remaining challenges and future perspectives for advancing HEs-based RZIBs are outlined.
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.
基金supported by the National Natural Science Foundation of China(51925304)Natural Science Foundation of Sichuan Province(2024NSFSC1023)Medical Research Program of Sichuan Province(Q23015).
文摘Bioactive molecules have shown great promise for effectively regulating various bone formation processes,rendering them attractive therapeutics for bone regeneration.However,the widespread application of bioactive molecules is limited by their low accumulation and short half-lives in vivo.Hydrogels have emerged as ideal carriers to address these challenges,offering the potential to prolong retention times at lesion sites,extend half-lives in vivo and mitigate side effects,avoid burst release,and promote adsorption under physiological conditions.This review systematically summarizes the recent advances in the development of bioactive molecule-loaded hydrogels for bone regeneration,encompassing applications in cranial defect repair,femoral defect repair,periodontal bone regeneration,and bone regeneration with underlying diseases.Additionally,this review discusses the current strategies aimed at improving the release profiles of bioactive molecules through stimuli-responsive delivery,carrier-assisted delivery,and sequential delivery.Finally,this review elucidates the existing challenges and future directions of hydrogel encapsulated bioactive molecules in the field of bone regeneration.
基金supported by the Innovative Research Group Project of the National Natural Science Foundation of China(T2121004)Key Programme(52235007)National Outstanding Youth Foundation of China(52325504).
文摘Hydrogel scaffolds have numerous potential applications in the tissue engineering field.However,tough hydrogel scaffolds implanted in vivo are seldom reported because it is difficult to balance biocompatibility and high mechanical properties.Inspired by Chinese ramen,we propose a universal fabricating method(printing-P,training-T,cross-linking-C,PTC&PCT)for tough hydrogel scaffolds to fill this gap.First,3D printing fabricates a hydrogel scaffold with desired structures(P).Then,the scaffold could have extraordinarily high mechanical properties and functional surface structure by cycle mechanical training with salting-out assistance(T).Finally,the training results are fixed by photo-cross-linking processing(C).The tough gelatin hydrogel scaffolds exhibit excellent tensile strength of 6.66 MPa(622-fold untreated)and have excellent biocompatibility.Furthermore,this scaffold possesses functional surface structures from nanometer to micron to millimeter,which can efficiently induce directional cell growth.Interestingly,this strategy can produce bionic human tissue with mechanical properties of 10 kPa-10 MPa by changing the type of salt,and many hydrogels,such as gelatin and silk,could be improved with PTC or PCT strategies.Animal experiments show that this scaffold can effectively promote the new generation of muscle fibers,blood vessels,and nerves within 4 weeks,prompting the rapid regeneration of large-volume muscle loss injuries.
基金supported by the Natural Science Foundation of Shandong Province,No.ZR2023MC168the National Natural Science Foundation of China,No.31670989the Key R&D Program of Shandong Province,No.2019GSF107037(all to CS).
文摘Vascular endothelial growth factor and its mimic peptide KLTWQELYQLKYKGI(QK)are widely used as the most potent angiogenic factors for the treatment of multiple ischemic diseases.However,conventional topical drug delivery often results in a burst release of the drug,leading to transient retention(inefficacy)and undesirable diffusion(toxicity)in vivo.Therefore,a drug delivery system that responds to changes in the microenvironment of tissue regeneration and controls vascular endothelial growth factor release is crucial to improve the treatment of ischemic stroke.Matrix metalloproteinase-2(MMP-2)is gradually upregulated after cerebral ischemia.Herein,vascular endothelial growth factor mimic peptide QK was self-assembled with MMP-2-cleaved peptide PLGLAG(TIMP)and customizable peptide amphiphilic(PA)molecules to construct nanofiber hydrogel PA-TIMP-QK.PA-TIMP-QK was found to control the delivery of QK by MMP-2 upregulation after cerebral ischemia/reperfusion and had a similar biological activity with vascular endothelial growth factor in vitro.The results indicated that PA-TIMP-QK promoted neuronal survival,restored local blood circulation,reduced blood-brain barrier permeability,and restored motor function.These findings suggest that the self-assembling nanofiber hydrogel PA-TIMP-QK may provide an intelligent drug delivery system that responds to the microenvironment and promotes regeneration and repair after cerebral ischemia/reperfusion injury.
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supported by the Scientific and Technological Project in Henan Province(242102231002)Henan Province Science and Technology Research and Development Program Joint Fund Advantageous Discipline Cultivation Project(No.232301420033)the Foundation for Outstanding Young Teachers in Universities of Henan Province(2021GGJS014).
文摘Bionic hydrogels offer significant advantages over conventional counterparts,boasting superior properties like enhanced adhesion,stretchability,conductivity,biocompatibility and versatile functionalities.Their physicochemical resemblance to biological tissues makes bionic hydrogels ideal interfaces for bioelectronic devices.In contrast,conventional hydrogels often exhibit inadequate performance,such as easy detachment,lack of good skin compliance,and inadequate conductivity,failing to meet the rigorous demands of bioelectronic applications.Bionic hydrogels,inspired by biological designs,exhibit exceptional physicochemical characteristics that fulfill diverse criteria for bioelectronic applications,driving the advancement of bioelectronic devices.This review first introduces a variety of materials used in the fabrication of bionic hydrogels,including natural polymers,synthetic polymers,and other materials.Then different mechanisms of hydrogel bionics,are categorized into material bionics,structural bionics,and functional bionics based on their bionic approaches.Subsequently,various applications of bionic hydrogels in the field of bioelectronics were introduced,including physiological signal monitoring,tissue engineering,and human-machine interactions.Lastly,the current development and future prospects of bionic hydrogels in bioelectronic devices are summarized.Hopefully,this comprehensive review could inspire advancements in bionic hydrogels for applications in bioelectronic devices.
文摘The management of chronic wounds remains a substantial challenge for healthcare providers. Inadequate wound care can result in serious complications, including infection, which may ultimately lead to amputation or even death. While traditional excipients exhibit some efficacy in promoting wound healing, they are not sufficiently effective in preventing wound infections. As an antimicrobial metal, copper has a long history in the antimicrobial field, and at the same time, wound auxiliaries with copper ions have also been used in the treatment of chronic wounds. To address the limitations of conventional wound dressings, including insufficient antimicrobial properties and limited capacity to promote wound healing, this study introduces a highly adhesive hydrogel with superior mechanical stability for non-invasive wound treatment. The hydrogel was composed of carboxymethyl chitosan, tannic acid and copper ions. The tannic acid solution was subjected to dropwise addition of CuCl2 solution to produce precipitation, and tannic acid/copper ions (TA/Cu2+) composite nanoparticles were prepared. Through topological adhesion, the CMCS with pH sensitivity has the ability to establish adhesive connections with a wide range of materials. The benefits of CMCS/TA/Cu2+ hydrogel, as a kind of wound closure and repair material, include efficient wound closure, and resistance against bacterial invasion while maintaining cleanliness. Additionally, it exhibits excellent tensile and mechanical stability that can facilitate effective closure and repair in dynamic areas like joint wounds. This promising hydrogel adhesive has demonstrated potential as a material for wound closure and restoration.
文摘Due to their high water content,stimulus responsiveness,and biocompatibility,hydrogels,which are functional materials with a three-dimensional network structure,are widely applied in fields such as biomedicine,environmental monitoring,and flexible electronics.This paper provides a systematic review of hydrogel charac-terization methods and their applications,focusing on primary evaluation techniques for physical properties(e.g.,mechanical strength,swelling behavior,and pore structure),chemical properties(e.g.,composition,crosslink density,and degradation behavior),biocompatibility,and functional properties(e.g.,drug release,environmental stimulus response,and conductivity).It analyzes the challenges currently faced by characterization methods,such as a lack of standardization,difficulties in dynamic monitoring,an insufficient micro-macro correlation,and poor adaptability to complex environments.It proposes solutions,such as a hierarchical standardization system,in situ imaging technology,cross-scale characterization,and biomimetic testing platforms.Looking ahead,hydrogel characterization techniques will evolve toward intelligent,real-time,multimodal coupling and standardized approaches.These techniques will provide superior technical support for precision medicine,environmental restoration,and flexible electronics.They will also offer systematic methodological guidance for the performance optimization and practical application of hydrogel materials.
基金Funded by the National Natural Science Foundation of China(No.22005151)the Natural Science Foundation of Nanjing University of Posts and Telecommunications(No.NY220127)。
文摘Polyvinyl alcohol(PVA)hydrogels doped with cyclohexane-1,2,3,4,5,6-hexacarboxylic acid(CHA)were successfully prepared during drying and swelling.Structural and morphological characterizations suggest the carboxyl and hydroxyl groups in the material undergo esterification during the preparation of the material,which contributes to the high transparency with 90%transmittance in the 400 to 800 nm range and robust mechanical properties of the material with a tensile strength at a break of 27.55 MPa.It is noteworthy that the bending and torsion angles exhibit a strong linear correlation with electrical resistance,enabling the monitoring of the bending motion state of each human body segment.
基金supported by the Natural Science Foundation of Guangdong Province(No.2022A1515012279)the Guangdong Basic and Applied Basic Research Foundation(No.2023A1515110126)。
文摘Repairing and regenerating cartilage defects in osteoarthritis patients remains challenging.Traditional treatments primarily offer symptom relief without addressing the underlying progression of the disease.Stem cell therapies provide a promising solution,yet they face limitations such as short retention times,low survival rates in vivo,and insufficient extracellular matrix(ECM)production.Stem cell-based hydrogel therapy offers a controlled microenvironment that can mitigate these challenges and enhance cell therapy effectiveness.This review evaluates the advantages and limitations of various stem cell types and hydrogel materials,summarizing recent advances in their combination for cartilage repair.The potential of stem cell-hydrogel therapies is highlighted,along with the remaining challenges and future directions for improving their clinical application.
基金the financial support of the National Natural Science Foundation of China(No.52075309)the Youth Innovation Team of Shaanxi Universities(21JP021)。
文摘Hydrogel has developed into a very important platform in solar interface evaporator.However,the current hydrogel evaporators are usually three-dimensional evaporators,which will consume a lot of raw materials.Thus,a new two-dimensional hydrogel evaporator is urgently needed to alleviate this problem.Here,a double layer hydrogel evaporator was designed by twice vacuum filtration.Furthermore,through the arched design and the introduction of concentrated brine drainage system,the hydrogel evaporator has enhanced water transportation and tailored water transportation path.Such a unique drainage evaporation system greatly improves the stability of the evaporator.Thereby,a good balance is established between photothermal conversion and water supply,and solar energy is utilized efficiently.It can remain stable in continuous evaporation for up to 12 h with an excellent evaporation rate of 2.70 kg m^(-2)h^(-1)under 1 sun irradiation.Meanwhile,the drainage system realized the 1.8×10^(-10)mol m^(-2)s^(-1)diffusion flux of concentrated brine.Through one-time freeze-drying preparation,an arch-shaped drainage evaporator was used to prepare an evaporation area of more than 20 cm^(2).With the self-made condensate collecting device in outdoor environment,the fresh water yield reaches 7.5 L m^(-2)d^(-1).This provides a new scheme for building a new hydrogel evaporator and solving the fresh water crisis.
基金funded by the National Natural Science Foundation of China(No.52475190 and 52275191)China Postdoctoral Science Foundation Funded Project(No.2024M751165)the Tribology Science Fund of State Key Laboratory of Tribology in Advanced Equipment(No.SKLTKF24B17).
文摘Pacinian Corpuscle(PC)is the largest tactile vibration receptor in mammalian skin,with a layered structure that enables signal amplification and high-pass filtering functions.Modern robots feature vibro-tactile sensors with excellent mechanical properties and fine resolution,but these sensors are prone to low-frequency noise interference when detecting high-frequency vibrations.In this study,a bionic PC with a longitudinally decreasing dynamic fractal structure is proposed.By creating a lumped parameter model of the PC’s layered structure,the bionic PC made of gelatin-chitosan based hydrogel can achieve high-pass filtering and specific frequency band signal amplification without requiring back-end circuits.The experimental results demonstrate that the bionic PC retains the structural characteristics of a natural PC,and the influence of structural factors,such as the number of layers in its shell,on filtration characteristics is explored.Additionally,a vibration source positioning experiment was conducted to simulate the earthquake sensing abilities of elephants.This natural structural design simplifies the filter circuit,is low-cost,cost-effective,stable in performance,and reduces redundancy in the robot’s signal circuit.Integrating this technology with robots can enhance their environmental perception,thereby improving the safety of interactions.
