Dental pulp-dentin complex defects remain a major unresolved problem in oral medicines.Clinical therapeutic methods including root canal therapy and vital pulp therapy are both considered as conservative strategies,wh...Dental pulp-dentin complex defects remain a major unresolved problem in oral medicines.Clinical therapeutic methods including root canal therapy and vital pulp therapy are both considered as conservative strategies,which are incapable of repairing the pulpdentin complex defects.Although biomaterial-based strategies show remarkable progress in antibacterial,anti-inflammatory,and pulp regeneration,the important modulatory effects of nerves within pulp cavity have been greatly overlooked,making it challenging to achieve functional pulp-dentin complex regeneration.In this study,we propose an injectable bioceramicscontaining composite hydrogel in combination of Li-Ca-Si(LCS)bioceramics and gelatin methacrylate matrix with photocrosslinking properties.Due to the sustained release of bioactive Li,Ca and Si ions from LCS,the composite hydrogels possess multiple functions of promoting the neurogenic differentiation of Schwann cells,odontogenic differentiation of dental pulp stem cells,and neurogenesis-odontogenesis couples in vitro.In addition,the in vivo results showed that LCS-containing composite hydrogel can significantly promote the pulp-dentin complex repair.More importantly,LCS bioceramics-containing composite hydrogel can induce the growth of nerve fibers,leading to the re-innervation of pulp tissues.Taken together,the study suggests that LCS bioceramics can induce the innervation of pulp-dentin complex repair,offering a referable strategy of designing multifunctional filling materials for functional periodontal tissue regeneration.展开更多
Granular composite(GC)hydrogels have attracted considerable interest in biomedical applications due to their versatile printability and exceptional mechanical properties.However,the lack of comprehensive design guidel...Granular composite(GC)hydrogels have attracted considerable interest in biomedical applications due to their versatile printability and exceptional mechanical properties.However,the lack of comprehensive design guidelines has limited their optimal engineering,as the factors influencing their mechanical performance and printability remain largely unexamined.In this study,we developed GC hydrogels by integrating microgels with interstitial matrices of photocrosslinkable gelatin methacrylate(GelMA).We utilized confocal microscopy and nanoindentation analyses to investigate the spatial distribution and mechanical behavior of these hydrogels.Our findings indicate that the mechanical and rheological properties of GC hydrogels can be precisely tailored by adjusting the volume fraction and size of the microgels.Furthermore,hydrogen bonds were identified as significant contributors to compressive performance,although they had minimal effect on cyclic mechanical behavior.Compared to bulk GelMA hydrogels,GC hydrogels demonstrated enhanced printability and remarkable superelasticity.As a proof of concept,we illustrated their dual printability in embedded printing to create prosthetic liver models for preoperative planning.This study provides valuable insights into the design and optimization of GC hydrogels for advanced biomedical applications.展开更多
Poly(vinyl alcohol) (PVA)/hydroxyapatite (HA) composite hydrogel specimens were prepared with 15% PVA and 1%,2%, 3%, 4% and 5% HA by repeated freezing-thawing. The tests of static and dynamic mechanical properties wer...Poly(vinyl alcohol) (PVA)/hydroxyapatite (HA) composite hydrogel specimens were prepared with 15% PVA and 1%,2%, 3%, 4% and 5% HA by repeated freezing-thawing. The tests of static and dynamic mechanical properties were carried out todiscuss the influence of different contents of HA and freezing-thawing cycles on the mechanical properties of PVA/HA compositehydrogel. The results of static mechanical tests showed that the PVA/HA composite hydrogel with 3% HA and ninefreezing-thawing cycles had excellent stress relaxation properties, higher relaxation ratio, lower stress equilibrium value andpresented better properties of creep and recovery. The results of dynamic mechanical test showed that the PVA/HA compositehydrogel with nine freezing-thawing cycles had higher storage modulus and loss modulus, so was the PVA/HA compositehydrogel with 3% HA.展开更多
Growing health awareness triggers the public's concern about health problems. People want a timely and comprehensive picture of their condition without frequent trips to the hospital for costly and cumbersome gene...Growing health awareness triggers the public's concern about health problems. People want a timely and comprehensive picture of their condition without frequent trips to the hospital for costly and cumbersome general check-ups. The wearable technique provides a continuous measurement method for health monitoring by tracking a person's physiological data and analyzing it locally or remotely.During the health monitoring process,different kinds of sensors convert physiological signals into electrical or optical signals that can be recorded and transmitted, consequently playing a crucial role in wearable techniques. Wearable application scenarios usually require sensors to possess excellent flexibility and stretchability. Thus, designing flexible and stretchable sensors with reliable performance is the key to wearable technology. Smart composite hydrogels, which have tunable electrical properties, mechanical properties, biocompatibility, and multi-stimulus sensitivity, are one of the best sensitive materials for wearable health monitoring. This review summarizes the common synthetic and performance optimization strategies of smart composite hydrogels and focuses on the current application of smart composite hydrogels in the field of wearable health monitoring.展开更多
With the rapid development of textile industry,a large amount of dye-contaminated effluents was produced and caused serious environmental problem.To remove the dye from effluents,adsorption materials have been applied...With the rapid development of textile industry,a large amount of dye-contaminated effluents was produced and caused serious environmental problem.To remove the dye from effluents,adsorption materials have been applied because of their relatively cheap,high efficiency,and easy handling.In this study,a novel composite hydrogel bead with unique multilayer flake structure was fabricated by alginate,acrylamide and attapulgite for dye adsorption.Acrylamide was grafted polymerization onto alginate to obtain alginate-g-poly(acrylamide).Then alginate-g-poly(acrylamide)was cross-linked by Ca2+ions in present of attapulgite to form composite hydrogel bead.Scanning electron microscopy(SEM)results show that the freeze dried composite hydrogel bead has multilayer flake structure incorporating attapulgite.Fourier transform infrared spectroscopy(FTIR)and Thermo-gravimetric analysis(TGA)results indicate that acrylamide has been successfully grafted polymerization on sodium alginate.Grafting polymerization of acrylamide onto sodium alginate obviously enhances the swelling of hydrogel bead.Incorporating of attapulgite into hydrogel bead effectively enhances the adsorption capacity to methylene blue and the maximum adsorption capacity is 155.7 mg g-1.Multilayer flake structure increases the adsorption area for methylene blue,but hinders the diffusion of methylene blue into the inner of composite hydrogel bead.High pH solution is beneficial to the adsorption.Pseudo-second order model and Fraundlinch model best describe the adsorption kinetic and isotherm,respectively.These results indicate that composite hydrogel bead is a promising adsorption material for dye-contaminated water treatment.展开更多
Water can be used as oxidant in conjunction with metal particles to form metal-water propellant to increase the energy of propellant.For this application,water needs to be stored in form of solid and capable of becomi...Water can be used as oxidant in conjunction with metal particles to form metal-water propellant to increase the energy of propellant.For this application,water needs to be stored in form of solid and capable of becoming liquid when use.Stable and thixotropic hydrogel has good potential as water-retaining material and oxidant of metal-based propellant.In this study,we prepared organic/inorganic composite hydrogels by combining inorganic gellants hectorite and fumed silica with organic gellant agarose,respectively.The total content of the gellants can be reduced to less than 2%by adding agarose.The influence of agarose on water content,phase transition temperature,centrifugal stability and other basic physical properties of composite hydrogels were discussed.The results show that the composite hydrogels have better thixotropy and stability than pure inorganic hydrogels,and the gel-sol transformation can be realized by applying shear force or heating to the phase transition temperature.The composite hydrogels have good shear thinning ability and improved mechanical stability.Fumed silica/agarose hydrogels have better physical stability,while the thixotropy and shear thinning ability of hectorite/agarose hydrogels are better.展开更多
Polyvinyl alcohol hydrogels have been used in wearable devices due to their good flexibility and biocompatibility.However,due to the low thermal conductivity(κ)of pure hydrogel,its further application in high power d...Polyvinyl alcohol hydrogels have been used in wearable devices due to their good flexibility and biocompatibility.However,due to the low thermal conductivity(κ)of pure hydrogel,its further application in high power devices is limited.To solve this problem,melamine sponge(MS)was used as the skeleton to wrap boron nitride nanosheets(BNNS)through repeated layering assembly,successfully preparing a three-dimensional(3D)boron nitride network(BNNS@MS),and PVA hydrogels were formed in the pores of the network.Due to the existence of the continuous phonon conduction network,the BNNS@MS/PVA exhibited an improvedκ.When the content of BNNS is about 6 wt.%,κof the hydrogel was increased to 1.12 W m^(-1)K^(-1),about two times higher than that of pure hydrogel.The solid heat conduction network and liquid convection network cooperate to achieve good thermal management ability.Combined with its high specific heat capacity,the composites have an important application prospect in the field of wearable flexible electronic thermal management.展开更多
Poly(vinyl alcohol)/hydroxylapatite(PVA/HA)composite hydrogel was prepared by repeated freezing and thawing.The water loss properties of the resultant hydrogel were investigated by using optical microscope.Long time i...Poly(vinyl alcohol)/hydroxylapatite(PVA/HA)composite hydrogel was prepared by repeated freezing and thawing.The water loss properties of the resultant hydrogel were investigated by using optical microscope.Long time immersion tests of PVA/HA composite hydrogel were carried out in the diluted calf serum solution to study the change laws of swelling properties with the freezing-thawing cycles and HA content.The micro-morphologies of PVA/HA composite hydrogel after long time immersion were observed by means of the high-accuracy 3D profiler.The results show that the swelling process of PVA/HA composite hydrogel is the converse process of its water loss.Long time swelling ratio curves of PVA/HA composite hydrogel in the calf serum solution are manifested as four stages of quick increase,decrease,slow decrease and stable balance,and its equilibrium swelling ratio decreases with the increase of freezing-thawing cycles and HA content.It is revealed that the network structure of the composite hydrogel immersed for a long period is significantly improved with the increase of HA content. Perfect network structures of PVA/HA composite hydrogel as well as full and equilibrium tissues after swelling equilibrium are obtained when the HA content is 3% and the number of freezing-thawing cycles is 7.展开更多
A series of the Guiqi polysaccharides/chitosan/alginate composite hydrogel microspheres(GPcM)with different particle sizes were prepared with Guiqi polysaccharides(GP),chitosan(CS)and sodium alginate(Alg).The optimum ...A series of the Guiqi polysaccharides/chitosan/alginate composite hydrogel microspheres(GPcM)with different particle sizes were prepared with Guiqi polysaccharides(GP),chitosan(CS)and sodium alginate(Alg).The optimum preparation process was also determined by single factor and orthogonal experiment analysis.The GPcM were characterized by fourier transform infrared spectroscopy(FT-IR),scanning electron microscope(SEM),drug loading efficiency test(LE),encapsulation efficiency test(EE)and in vitro release study.The results showed that the Guiqi polysaccharides chitosan hydrogel(GPCH)and sodium alginate hydrogel(SAH)formed a crossover system in GPcM.The GPcM have a uniform particle size ranging from 395.1μm to 841.5μm.The drug loading efficiency and encapsulation efficiency of the GPcM were 56.3%and 72.6%,respectively.The bovine serum albumin(BSA)loaded in the GPcM released slowly within 180 h.The results suggested that the GPcM may have potential application value in drug sustained and controlled release system.展开更多
Cellulose nanofiber(CNF)was isolated from Okara using deep eutectic solvent(DES)with high-speed stirring.The composite hydrogels obtained by using different proportions of CNF and sodium alginate(SA)had different prop...Cellulose nanofiber(CNF)was isolated from Okara using deep eutectic solvent(DES)with high-speed stirring.The composite hydrogels obtained by using different proportions of CNF and sodium alginate(SA)had different properties.The CNF/SA composite hydrogels were analyzed using Fourier transform infrared spectroscopy and scanning electron microscopy and tested for compression properties,rheological properties,water content,and swelling degree.Physical crosslinking between SA and Ca^(2+),and different degrees of hydrogen bond formation between SA and CNF were observed.The CNF/SA composite hydrogel have great potential as reinforcements in eco-friendly composite hydrogels for diverse applications.展开更多
Theγ-PGA-based food hydrogel exhibits good biodegradability and biocompatibility,and is non-toxic to humans.In this study,a novel hydrogel(γ-PGA/casein composite hydrogel)was prepared by combining casein with y-PGA ...Theγ-PGA-based food hydrogel exhibits good biodegradability and biocompatibility,and is non-toxic to humans.In this study,a novel hydrogel(γ-PGA/casein composite hydrogel)was prepared by combining casein with y-PGA separated from natto using microbial transglutaminase(MTG)as the crosslinker.The effects of the MTG mass concentration,gelation time,crosslinking temperature,pH,and the mass ratio of y-PGA to casein on the crosslinking ratio of y-PGA and swelling ratio of theγ-PGA/casein hydrogel were investigated.Furthermore,the synthesis conditions were optimized by response surface methodology to optimize three important factors,i.e.crosslinking temperature,pH and the mass ratio of y-PGA to casein.The results of single factor experiments showed that the MTG mass concentration and crosslinking time had little impacts on the crosslinking ratio of y-PGA and the swelling ratio;the preferred MTG mass concentration,crosslinking time,temperature and pH were selected as 0.3%,7 h,40℃and 7.5;and the preferred mass ratio ofγ-PGA to casein was 0.1 for the crosslinking ratio ofγ-PGA and 0.2 for the swelling ratio.The response surface experiment results showed that the optimum crosslinking temperature,pH and the mass ratio of y-PGA to casein ratio were 42.4℃,7.33,and 0.18,respectively.Under these optimum conditions,the predicted crosslinking ratio of y-PGA and swelling ratio reached 90.35%and 112.07%,which were highly consistent with the experimental values(88.00%and 115.87%).Theγ-PGA/casein composite hydrogel developed in this study shows promising application potential in food industry,biomedical field,and cosmetic industry.展开更多
Corresponding author’s name was incorrectly written as“Dadang Guo”instead of“Dagang Guo”.The correct author name should be“Dagang Guo”.The authors would like to apologise for any inconvenience caused.
Designing advanced hydrogels with controlled mechanical properties,drug delivery manner and multifunctional properties will be beneficial for biomedical applications.However,the further development of hydrogel is limi...Designing advanced hydrogels with controlled mechanical properties,drug delivery manner and multifunctional properties will be beneficial for biomedical applications.However,the further development of hydrogel is limited due to its poor mechanical property and structural diversity.Hydrogels combined with polymeric micelles to obtain micelle-hydrogel composites have been designed for synergistic enhancement of each original properties.Incorporation polymeric micelles into hydrogel networks can not only enhance the mechanical property of hydrogel,but also expand the functionality of hydrogel.Recent advances in polymeric micelle-hydrogel composites are herein reviewed with a focus on three typical micelle incorporation methods.In this review,we will also highlight some emerging biomedical applications in developing micelle-hydrogel composite with multiple functionalities.In addition,further development and application prospects of the micelle-hydrogels composites have also been addressed.展开更多
Wound healing in cases of excessive inflammation poses a significant challenge due to compromised neovascularization.Here,we propose a multi-functional composite hydrogel engineered to overcome such conditions through...Wound healing in cases of excessive inflammation poses a significant challenge due to compromised neovascularization.Here,we propose a multi-functional composite hydrogel engineered to overcome such conditions through recruitment and activation of macrophages with adapted degradation of the hydrogel.The composite hydrogel(G-TSrP)is created by combining gelatin methacryloyl(GelMA)and nanoparticles(TSrP)composed of tannic acid(TA)and Sr^(2+).These nanoparticles are prepared using a one-step mineralization process assisted by metal-phenolic network formation.G-TSrP exhibits the ability to eliminate reactive oxygen species and direct polarization of macrophages toward M2 phenotype.It has been observed that the liberation of TA and Sr^(2+)from G-TSrP actively facilitate the recruitment and up-regulation of the expression of extracellular matrix remodeling genes of macrophages,and thereby,coordinate in vivo adapted degradation of the G-TSrP.Most significantly,G-TSrP accelerates angiogenesis despite the TA’s inhibitory properties,which are counteracted by the released Sr^(2+).Moreover,G-TSrP enhances wound closure under inflammation and promotes normal tissue formation with strong vessel growth.Genetic analysis confirms macrophage-mediated wound healing by the composite hydrogel.Collectively,these findings pave the way for the development of biomaterials that promote wound healing by creating regenerative environment.展开更多
Three-dimensional printing technologies exhibit tremendous potential in the advancing fields of tissue engineering and regenerative medicine due to the precise spatial control over depositing the biomaterial.Despite t...Three-dimensional printing technologies exhibit tremendous potential in the advancing fields of tissue engineering and regenerative medicine due to the precise spatial control over depositing the biomaterial.Despite their widespread utilization and numerous advantages,the development of suitable novel biomaterials for extrusion-based 3D printing of scaffolds that support cell attachment,proliferation,and vascularization remains a challenge.Multi-material composite hydrogels present incredible potential in this field.Thus,in this work,a multi-material composite hydrogel with a promising formulation of chitosan/gelatin functionalized with egg white was developed,which provides good printability and shape fidelity.In addition,a series of comparative analyses of different crosslinking agents and processes based on tripolyphosphate(TPP),genipin(GP),and glutaraldehyde(GTA)were investigated and compared to select the ideal crosslinking strategy to enhance the physicochemical and biological properties of the fabricated scaffolds.All of the results indicate that the composite hydrogel and the resulting scaffolds utilizing TPP crosslinking have great potential in tissue engineering,especially for supporting neo-vessel growth into the scaffold and promoting angiogenesis within engineered tissues.展开更多
Bioactive hydrogel materials have great potential for applications in bone tissue engineering.However,fabrication of functional hydrogels that mimic the natural bone extracellular matrix(ECM)remains a challenge,becaus...Bioactive hydrogel materials have great potential for applications in bone tissue engineering.However,fabrication of functional hydrogels that mimic the natural bone extracellular matrix(ECM)remains a challenge,because they need to provide mechanical support and embody physiological cues for angiogenesis and osteogenesis.Inspired by the features of ECM,we constructed a dual-component composite hydrogel comprising interpenetrating polymer networks of gelatin methacryloyl(GelMA)and deoxyribonucleic acid(DNA).Within the composite hydrogel,the GelMA network serves as the backbone for mechanical and biological stability,whereas the DNA network realizes dynamic capabilities(e.g.,stress relaxation),thereby promoting cell proliferation and osteogenic differentiation.Furthermore,functional aptamers(Apt19S and AptV)are readily attached to the DNA network to recruit bone marrow mesenchymal stem cells(BMSCs)and achieve sustained release of loaded vascular endothelial growth factor towards angiogenesis.Our results showed that the composite hydrogel could facilitate the adhesion of BMSCs,promote osteogenic differentiation by activating focal adhesion kinase(FAK)/phosphatidylinositol 3-kinase(PI3K)/protein kinase B(Akt)/β-Catenin signaling pathway,and eventually enhance vascularized bone regeneration.This study shows that the multifunctional composite hydrogel of GelMA and DNA can successfully simulate the biological functions of natural bone ECM and has great potential for repairing bone defects.展开更多
Halloysite nanotube-composited thermo-responsive hydrogel system has been successfully developed for controlled drug release by copolymerization of N-isopropylacrylamide （NIPAM） with silane-modified halloysite nanot...Halloysite nanotube-composited thermo-responsive hydrogel system has been successfully developed for controlled drug release by copolymerization of N-isopropylacrylamide （NIPAM） with silane-modified halloysite nanotubes （HNT） through thermally initiated free-radical polymerization. With methylene blue as a model drug, thermo-responsive drug release results demonstrate that the drug release from the nanotubes in the composited hy-drogel can^be well controlled by manipulating the environmental temperature. When the hydrogel network is swol- len at temperature below the lower critical solution temperature （LCST）, drug releases steadily from lumens of the embedded nanotubes, whereas the drug release stops when hydrogel shrinks at temperature above the LCST. The release of model drug from the HNT-composited hydrogel matches well with its thermo-responsive volume phasetransition, and shows characteristics of well controlled release. The design strategy and release results of the pro- posed novel HNT-composited thermo-responsive hydrogel system provide valuable guidance for designing respon- s_i_ve nanocomposites for controlled-release of active agents.展开更多
Low back pain is one of the most serious public health problems worldwide and the major clinical manifestation of intervertebral disc degeneration(IVDD).The key pathological change during IVDD is dysfunction of the an...Low back pain is one of the most serious public health problems worldwide and the major clinical manifestation of intervertebral disc degeneration(IVDD).The key pathological change during IVDD is dysfunction of the annulus fibrosus(AF).However,due to the lack of an in-depth understanding of AF biology,the methods to reconstruct the AF are very limited.In this study,the mice AF cell atlas were decoded by single-cell RNA sequencing to provide a guide for AF reconstruction.The results first identify a new population of AF cells,fibrochondrocyte-like AF cells,which synthesize both collagen Ⅰ and collagen Ⅱ and are potential functional cells for AF reconstruction.According to the dual features of the AF extracellular matrix,a composite hydrogel based on the acylation of methacrylated silk fibroin with methacrylated hyaluronic acid was produced.To obtain the ability to stimulate differentiation,the composite hydrogels were combined with a fibrochondrocyte-inducing supplement.Finally,reconstruction of the AF defects,by the novel AF stem cell-loaded composite hydrogel,could be observed,its amount of chondroid matrices recovered to 31.7% of AF aera which is significantly higher than that in other control groups.In summary,this study decodes the AF cell atlas,based on which a novel strategy for AF reconstruction is proposed.展开更多
基金funded by the National Key R&D Program of China(2022YFC2405904)the National Natural Science Foundation of China(52272284,32225028)+1 种基金Joint Research Unit Plan of the Chinese Academy of Sciences(121631ZYLH20240014)the Science and Technology Commission of Shanghai Municipality(24520750100)。
文摘Dental pulp-dentin complex defects remain a major unresolved problem in oral medicines.Clinical therapeutic methods including root canal therapy and vital pulp therapy are both considered as conservative strategies,which are incapable of repairing the pulpdentin complex defects.Although biomaterial-based strategies show remarkable progress in antibacterial,anti-inflammatory,and pulp regeneration,the important modulatory effects of nerves within pulp cavity have been greatly overlooked,making it challenging to achieve functional pulp-dentin complex regeneration.In this study,we propose an injectable bioceramicscontaining composite hydrogel in combination of Li-Ca-Si(LCS)bioceramics and gelatin methacrylate matrix with photocrosslinking properties.Due to the sustained release of bioactive Li,Ca and Si ions from LCS,the composite hydrogels possess multiple functions of promoting the neurogenic differentiation of Schwann cells,odontogenic differentiation of dental pulp stem cells,and neurogenesis-odontogenesis couples in vitro.In addition,the in vivo results showed that LCS-containing composite hydrogel can significantly promote the pulp-dentin complex repair.More importantly,LCS bioceramics-containing composite hydrogel can induce the growth of nerve fibers,leading to the re-innervation of pulp tissues.Taken together,the study suggests that LCS bioceramics can induce the innervation of pulp-dentin complex repair,offering a referable strategy of designing multifunctional filling materials for functional periodontal tissue regeneration.
基金support from the National Natural Science Foundation of China(Nos.U21A20394 and 52305314)the Beijing Natural Science Foundation(Nos.7252285 and L246001)the National Key Research and Development Program of China(No.2023YFB4605800)。
文摘Granular composite(GC)hydrogels have attracted considerable interest in biomedical applications due to their versatile printability and exceptional mechanical properties.However,the lack of comprehensive design guidelines has limited their optimal engineering,as the factors influencing their mechanical performance and printability remain largely unexamined.In this study,we developed GC hydrogels by integrating microgels with interstitial matrices of photocrosslinkable gelatin methacrylate(GelMA).We utilized confocal microscopy and nanoindentation analyses to investigate the spatial distribution and mechanical behavior of these hydrogels.Our findings indicate that the mechanical and rheological properties of GC hydrogels can be precisely tailored by adjusting the volume fraction and size of the microgels.Furthermore,hydrogen bonds were identified as significant contributors to compressive performance,although they had minimal effect on cyclic mechanical behavior.Compared to bulk GelMA hydrogels,GC hydrogels demonstrated enhanced printability and remarkable superelasticity.As a proof of concept,we illustrated their dual printability in embedded printing to create prosthetic liver models for preoperative planning.This study provides valuable insights into the design and optimization of GC hydrogels for advanced biomedical applications.
基金supported by National Natural Science Foundation of China(Grant No.50875252)Program for New Century Excellent TaIents in University (Grant No.NCET-06-0479)Natural Science Foundation of Jiangsu Proyince (Grant No.BK2008005)
文摘Poly(vinyl alcohol) (PVA)/hydroxyapatite (HA) composite hydrogel specimens were prepared with 15% PVA and 1%,2%, 3%, 4% and 5% HA by repeated freezing-thawing. The tests of static and dynamic mechanical properties were carried out todiscuss the influence of different contents of HA and freezing-thawing cycles on the mechanical properties of PVA/HA compositehydrogel. The results of static mechanical tests showed that the PVA/HA composite hydrogel with 3% HA and ninefreezing-thawing cycles had excellent stress relaxation properties, higher relaxation ratio, lower stress equilibrium value andpresented better properties of creep and recovery. The results of dynamic mechanical test showed that the PVA/HA compositehydrogel with nine freezing-thawing cycles had higher storage modulus and loss modulus, so was the PVA/HA compositehydrogel with 3% HA.
基金financial support from the National Natural Science Foundation of China (No. 61801525)the Guangdong Basic and Applied Basic Research Foundation (Nos. 2020A1515010693, 2021A1515110269)+1 种基金the Fundamental Research Funds for the Central Universities, Sun Yatsen University (No. 22lgqb17)the Independent Fund of the State Key Laboratory of Optoelectronic Materials and Technologies (Sun Yat-sen University) under grant No. OEMT-2022-ZRC-05。
文摘Growing health awareness triggers the public's concern about health problems. People want a timely and comprehensive picture of their condition without frequent trips to the hospital for costly and cumbersome general check-ups. The wearable technique provides a continuous measurement method for health monitoring by tracking a person's physiological data and analyzing it locally or remotely.During the health monitoring process,different kinds of sensors convert physiological signals into electrical or optical signals that can be recorded and transmitted, consequently playing a crucial role in wearable techniques. Wearable application scenarios usually require sensors to possess excellent flexibility and stretchability. Thus, designing flexible and stretchable sensors with reliable performance is the key to wearable technology. Smart composite hydrogels, which have tunable electrical properties, mechanical properties, biocompatibility, and multi-stimulus sensitivity, are one of the best sensitive materials for wearable health monitoring. This review summarizes the common synthetic and performance optimization strategies of smart composite hydrogels and focuses on the current application of smart composite hydrogels in the field of wearable health monitoring.
基金for Doctors of Jinling Institute of Technology(Grant No.jit-b-201415)the Natural Science Foundation for Colleges and Universities of Jiangsu Province(Grant No.12KJD150006)for the financial support of this research.
文摘With the rapid development of textile industry,a large amount of dye-contaminated effluents was produced and caused serious environmental problem.To remove the dye from effluents,adsorption materials have been applied because of their relatively cheap,high efficiency,and easy handling.In this study,a novel composite hydrogel bead with unique multilayer flake structure was fabricated by alginate,acrylamide and attapulgite for dye adsorption.Acrylamide was grafted polymerization onto alginate to obtain alginate-g-poly(acrylamide).Then alginate-g-poly(acrylamide)was cross-linked by Ca2+ions in present of attapulgite to form composite hydrogel bead.Scanning electron microscopy(SEM)results show that the freeze dried composite hydrogel bead has multilayer flake structure incorporating attapulgite.Fourier transform infrared spectroscopy(FTIR)and Thermo-gravimetric analysis(TGA)results indicate that acrylamide has been successfully grafted polymerization on sodium alginate.Grafting polymerization of acrylamide onto sodium alginate obviously enhances the swelling of hydrogel bead.Incorporating of attapulgite into hydrogel bead effectively enhances the adsorption capacity to methylene blue and the maximum adsorption capacity is 155.7 mg g-1.Multilayer flake structure increases the adsorption area for methylene blue,but hinders the diffusion of methylene blue into the inner of composite hydrogel bead.High pH solution is beneficial to the adsorption.Pseudo-second order model and Fraundlinch model best describe the adsorption kinetic and isotherm,respectively.These results indicate that composite hydrogel bead is a promising adsorption material for dye-contaminated water treatment.
基金the Haihe Laboratory of Sustainable Chemical Transformations for financial support。
文摘Water can be used as oxidant in conjunction with metal particles to form metal-water propellant to increase the energy of propellant.For this application,water needs to be stored in form of solid and capable of becoming liquid when use.Stable and thixotropic hydrogel has good potential as water-retaining material and oxidant of metal-based propellant.In this study,we prepared organic/inorganic composite hydrogels by combining inorganic gellants hectorite and fumed silica with organic gellant agarose,respectively.The total content of the gellants can be reduced to less than 2%by adding agarose.The influence of agarose on water content,phase transition temperature,centrifugal stability and other basic physical properties of composite hydrogels were discussed.The results show that the composite hydrogels have better thixotropy and stability than pure inorganic hydrogels,and the gel-sol transformation can be realized by applying shear force or heating to the phase transition temperature.The composite hydrogels have good shear thinning ability and improved mechanical stability.Fumed silica/agarose hydrogels have better physical stability,while the thixotropy and shear thinning ability of hectorite/agarose hydrogels are better.
基金the National Natural Science Foundation of China(Nos.52173078,52130303,and 51803151)the Young Elite Scientists Sponsorship Program by CAST(No.2019QNRC001)。
文摘Polyvinyl alcohol hydrogels have been used in wearable devices due to their good flexibility and biocompatibility.However,due to the low thermal conductivity(κ)of pure hydrogel,its further application in high power devices is limited.To solve this problem,melamine sponge(MS)was used as the skeleton to wrap boron nitride nanosheets(BNNS)through repeated layering assembly,successfully preparing a three-dimensional(3D)boron nitride network(BNNS@MS),and PVA hydrogels were formed in the pores of the network.Due to the existence of the continuous phonon conduction network,the BNNS@MS/PVA exhibited an improvedκ.When the content of BNNS is about 6 wt.%,κof the hydrogel was increased to 1.12 W m^(-1)K^(-1),about two times higher than that of pure hydrogel.The solid heat conduction network and liquid convection network cooperate to achieve good thermal management ability.Combined with its high specific heat capacity,the composites have an important application prospect in the field of wearable flexible electronic thermal management.
基金supported by the Key Program of the National Natural Science Foundation of China (Grant No. 50535050)the National Natural Science Foundation of China (Grant No. 50875252)+1 种基金the Program for New Century Excellent Talents in University (Grant No. NCET-06-0479)the Natural Science Foundation of Jiangsu Province (Grant No. BK2008005)
文摘Poly(vinyl alcohol)/hydroxylapatite(PVA/HA)composite hydrogel was prepared by repeated freezing and thawing.The water loss properties of the resultant hydrogel were investigated by using optical microscope.Long time immersion tests of PVA/HA composite hydrogel were carried out in the diluted calf serum solution to study the change laws of swelling properties with the freezing-thawing cycles and HA content.The micro-morphologies of PVA/HA composite hydrogel after long time immersion were observed by means of the high-accuracy 3D profiler.The results show that the swelling process of PVA/HA composite hydrogel is the converse process of its water loss.Long time swelling ratio curves of PVA/HA composite hydrogel in the calf serum solution are manifested as four stages of quick increase,decrease,slow decrease and stable balance,and its equilibrium swelling ratio decreases with the increase of freezing-thawing cycles and HA content.It is revealed that the network structure of the composite hydrogel immersed for a long period is significantly improved with the increase of HA content. Perfect network structures of PVA/HA composite hydrogel as well as full and equilibrium tissues after swelling equilibrium are obtained when the HA content is 3% and the number of freezing-thawing cycles is 7.
基金by National Natural Science Foundation of China(81560737,31860250)Natural Science Foundation of Gansu Province(18JR3RA148)+1 种基金Guangxi Provincial Natural Science Fund of China(2016GXNSFAA380234)Fundamental Research Funds for Key Laboratory of Drug Screening and Deep Processing for Traditional Chinese and Tibetan Medicine of Gansu Province(20180801).
文摘A series of the Guiqi polysaccharides/chitosan/alginate composite hydrogel microspheres(GPcM)with different particle sizes were prepared with Guiqi polysaccharides(GP),chitosan(CS)and sodium alginate(Alg).The optimum preparation process was also determined by single factor and orthogonal experiment analysis.The GPcM were characterized by fourier transform infrared spectroscopy(FT-IR),scanning electron microscope(SEM),drug loading efficiency test(LE),encapsulation efficiency test(EE)and in vitro release study.The results showed that the Guiqi polysaccharides chitosan hydrogel(GPCH)and sodium alginate hydrogel(SAH)formed a crossover system in GPcM.The GPcM have a uniform particle size ranging from 395.1μm to 841.5μm.The drug loading efficiency and encapsulation efficiency of the GPcM were 56.3%and 72.6%,respectively.The bovine serum albumin(BSA)loaded in the GPcM released slowly within 180 h.The results suggested that the GPcM may have potential application value in drug sustained and controlled release system.
基金This work was supported by the Foundation of State Key Laboratory of Pulp and Paper Engineering(201819)the project of Shaanxi Provincial Department of Education Key Laboratory Research Open Fund(Grant No.17JS017)the Project of Shaanxi University of Science and Technology Research Initial Fund(Grant No.BJ15-29).
文摘Cellulose nanofiber(CNF)was isolated from Okara using deep eutectic solvent(DES)with high-speed stirring.The composite hydrogels obtained by using different proportions of CNF and sodium alginate(SA)had different properties.The CNF/SA composite hydrogels were analyzed using Fourier transform infrared spectroscopy and scanning electron microscopy and tested for compression properties,rheological properties,water content,and swelling degree.Physical crosslinking between SA and Ca^(2+),and different degrees of hydrogen bond formation between SA and CNF were observed.The CNF/SA composite hydrogel have great potential as reinforcements in eco-friendly composite hydrogels for diverse applications.
基金supported by the Doctoral Scientific Research Start-up Foundation from Henan University of Technology(No:2018BS072)。
文摘Theγ-PGA-based food hydrogel exhibits good biodegradability and biocompatibility,and is non-toxic to humans.In this study,a novel hydrogel(γ-PGA/casein composite hydrogel)was prepared by combining casein with y-PGA separated from natto using microbial transglutaminase(MTG)as the crosslinker.The effects of the MTG mass concentration,gelation time,crosslinking temperature,pH,and the mass ratio of y-PGA to casein on the crosslinking ratio of y-PGA and swelling ratio of theγ-PGA/casein hydrogel were investigated.Furthermore,the synthesis conditions were optimized by response surface methodology to optimize three important factors,i.e.crosslinking temperature,pH and the mass ratio of y-PGA to casein.The results of single factor experiments showed that the MTG mass concentration and crosslinking time had little impacts on the crosslinking ratio of y-PGA and the swelling ratio;the preferred MTG mass concentration,crosslinking time,temperature and pH were selected as 0.3%,7 h,40℃and 7.5;and the preferred mass ratio ofγ-PGA to casein was 0.1 for the crosslinking ratio ofγ-PGA and 0.2 for the swelling ratio.The response surface experiment results showed that the optimum crosslinking temperature,pH and the mass ratio of y-PGA to casein ratio were 42.4℃,7.33,and 0.18,respectively.Under these optimum conditions,the predicted crosslinking ratio of y-PGA and swelling ratio reached 90.35%and 112.07%,which were highly consistent with the experimental values(88.00%and 115.87%).Theγ-PGA/casein composite hydrogel developed in this study shows promising application potential in food industry,biomedical field,and cosmetic industry.
文摘Corresponding author’s name was incorrectly written as“Dadang Guo”instead of“Dagang Guo”.The correct author name should be“Dagang Guo”.The authors would like to apologise for any inconvenience caused.
基金the Natural Science Basic Research Program of Shaanxi Province(No.2023-JC-YB-101)the Basic Science Research Program of Shaanxi Basic Sciences Institute(Chemistry,Biology)(No.22JHQ079)National Natural Science Foundation of China(No.82272150).
文摘Designing advanced hydrogels with controlled mechanical properties,drug delivery manner and multifunctional properties will be beneficial for biomedical applications.However,the further development of hydrogel is limited due to its poor mechanical property and structural diversity.Hydrogels combined with polymeric micelles to obtain micelle-hydrogel composites have been designed for synergistic enhancement of each original properties.Incorporation polymeric micelles into hydrogel networks can not only enhance the mechanical property of hydrogel,but also expand the functionality of hydrogel.Recent advances in polymeric micelle-hydrogel composites are herein reviewed with a focus on three typical micelle incorporation methods.In this review,we will also highlight some emerging biomedical applications in developing micelle-hydrogel composite with multiple functionalities.In addition,further development and application prospects of the micelle-hydrogels composites have also been addressed.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIT)(No.RS-2023-00207746,RS-2023-00207983)a grant of the Korea Health Technology R&D Project through the Korea Health Industry Development Institute(KHIDI)funded by the Ministry of Health&Welfare,Republic of Korea(grant number:HI19C075300).
文摘Wound healing in cases of excessive inflammation poses a significant challenge due to compromised neovascularization.Here,we propose a multi-functional composite hydrogel engineered to overcome such conditions through recruitment and activation of macrophages with adapted degradation of the hydrogel.The composite hydrogel(G-TSrP)is created by combining gelatin methacryloyl(GelMA)and nanoparticles(TSrP)composed of tannic acid(TA)and Sr^(2+).These nanoparticles are prepared using a one-step mineralization process assisted by metal-phenolic network formation.G-TSrP exhibits the ability to eliminate reactive oxygen species and direct polarization of macrophages toward M2 phenotype.It has been observed that the liberation of TA and Sr^(2+)from G-TSrP actively facilitate the recruitment and up-regulation of the expression of extracellular matrix remodeling genes of macrophages,and thereby,coordinate in vivo adapted degradation of the G-TSrP.Most significantly,G-TSrP accelerates angiogenesis despite the TA’s inhibitory properties,which are counteracted by the released Sr^(2+).Moreover,G-TSrP enhances wound closure under inflammation and promotes normal tissue formation with strong vessel growth.Genetic analysis confirms macrophage-mediated wound healing by the composite hydrogel.Collectively,these findings pave the way for the development of biomaterials that promote wound healing by creating regenerative environment.
基金The authors acknowledge the funding support from the National Natural Science Foundation of China(Nos.52175474 and 51775324)the China Scholarship Council(No.202006890054).
文摘Three-dimensional printing technologies exhibit tremendous potential in the advancing fields of tissue engineering and regenerative medicine due to the precise spatial control over depositing the biomaterial.Despite their widespread utilization and numerous advantages,the development of suitable novel biomaterials for extrusion-based 3D printing of scaffolds that support cell attachment,proliferation,and vascularization remains a challenge.Multi-material composite hydrogels present incredible potential in this field.Thus,in this work,a multi-material composite hydrogel with a promising formulation of chitosan/gelatin functionalized with egg white was developed,which provides good printability and shape fidelity.In addition,a series of comparative analyses of different crosslinking agents and processes based on tripolyphosphate(TPP),genipin(GP),and glutaraldehyde(GTA)were investigated and compared to select the ideal crosslinking strategy to enhance the physicochemical and biological properties of the fabricated scaffolds.All of the results indicate that the composite hydrogel and the resulting scaffolds utilizing TPP crosslinking have great potential in tissue engineering,especially for supporting neo-vessel growth into the scaffold and promoting angiogenesis within engineered tissues.
基金supported by National Natural Science Foundation of China(Grant Nos.52171075,52103172,82271589)Science and Technology Commission of Shanghai Municipality(Grant Nos.21DZ2294700,21ZR1439400)+3 种基金Opening Project of Shanghai Key Laboratory of Orthopaedic Implant(Grant No.KFKT2021001)the Non-profit Central Research Institute Fund of Chinese Academy of Medical Sciences(Grant No.2023-JKCS-14)Incubating Program for National Program of Renji Hospital,Shanghai Jiao Tong University School of Medicine(Grant No.RJTJ23-PY-053)“Clinic Plus”Outstanding Project of Shanghai Key Laboratory for Nucleic Acid Chemistry and Nanomedicine(Grant No.2021ZYA009).
文摘Bioactive hydrogel materials have great potential for applications in bone tissue engineering.However,fabrication of functional hydrogels that mimic the natural bone extracellular matrix(ECM)remains a challenge,because they need to provide mechanical support and embody physiological cues for angiogenesis and osteogenesis.Inspired by the features of ECM,we constructed a dual-component composite hydrogel comprising interpenetrating polymer networks of gelatin methacryloyl(GelMA)and deoxyribonucleic acid(DNA).Within the composite hydrogel,the GelMA network serves as the backbone for mechanical and biological stability,whereas the DNA network realizes dynamic capabilities(e.g.,stress relaxation),thereby promoting cell proliferation and osteogenic differentiation.Furthermore,functional aptamers(Apt19S and AptV)are readily attached to the DNA network to recruit bone marrow mesenchymal stem cells(BMSCs)and achieve sustained release of loaded vascular endothelial growth factor towards angiogenesis.Our results showed that the composite hydrogel could facilitate the adhesion of BMSCs,promote osteogenic differentiation by activating focal adhesion kinase(FAK)/phosphatidylinositol 3-kinase(PI3K)/protein kinase B(Akt)/β-Catenin signaling pathway,and eventually enhance vascularized bone regeneration.This study shows that the multifunctional composite hydrogel of GelMA and DNA can successfully simulate the biological functions of natural bone ECM and has great potential for repairing bone defects.
基金Supported by the National ]qatural Science Foundation of China （20906064）, the National Basic Research Program of China （2009CB623407）, the Program for Changjiang Scholars and Innovative Research Team in University （IRTl163）, and the Foundation for the Author of National Excellent Doctoral Dissertation of China （201163）.
文摘Halloysite nanotube-composited thermo-responsive hydrogel system has been successfully developed for controlled drug release by copolymerization of N-isopropylacrylamide （NIPAM） with silane-modified halloysite nanotubes （HNT） through thermally initiated free-radical polymerization. With methylene blue as a model drug, thermo-responsive drug release results demonstrate that the drug release from the nanotubes in the composited hy-drogel can^be well controlled by manipulating the environmental temperature. When the hydrogel network is swol- len at temperature below the lower critical solution temperature （LCST）, drug releases steadily from lumens of the embedded nanotubes, whereas the drug release stops when hydrogel shrinks at temperature above the LCST. The release of model drug from the HNT-composited hydrogel matches well with its thermo-responsive volume phasetransition, and shows characteristics of well controlled release. The design strategy and release results of the pro- posed novel HNT-composited thermo-responsive hydrogel system provide valuable guidance for designing respon- s_i_ve nanocomposites for controlled-release of active agents.
基金the financial support of the following funds for our study:The State Key Program of National Natural Science Foundation of China(Grant nos.81730065 to Z.L.,82130070 to L.Y.)Projects of International Cooperation and Exchanges of National Natural Science Foundation of China(Grant nos.82020108019 to Z.L.).
文摘Low back pain is one of the most serious public health problems worldwide and the major clinical manifestation of intervertebral disc degeneration(IVDD).The key pathological change during IVDD is dysfunction of the annulus fibrosus(AF).However,due to the lack of an in-depth understanding of AF biology,the methods to reconstruct the AF are very limited.In this study,the mice AF cell atlas were decoded by single-cell RNA sequencing to provide a guide for AF reconstruction.The results first identify a new population of AF cells,fibrochondrocyte-like AF cells,which synthesize both collagen Ⅰ and collagen Ⅱ and are potential functional cells for AF reconstruction.According to the dual features of the AF extracellular matrix,a composite hydrogel based on the acylation of methacrylated silk fibroin with methacrylated hyaluronic acid was produced.To obtain the ability to stimulate differentiation,the composite hydrogels were combined with a fibrochondrocyte-inducing supplement.Finally,reconstruction of the AF defects,by the novel AF stem cell-loaded composite hydrogel,could be observed,its amount of chondroid matrices recovered to 31.7% of AF aera which is significantly higher than that in other control groups.In summary,this study decodes the AF cell atlas,based on which a novel strategy for AF reconstruction is proposed.
