Control crosslink network and chain connectivity are essential to develop shape memory polymers(SMPs)with high shape memory capabilities,adjustable response temperature,and satisfying mechanistical properties.In this ...Control crosslink network and chain connectivity are essential to develop shape memory polymers(SMPs)with high shape memory capabilities,adjustable response temperature,and satisfying mechanistical properties.In this study,novel poly(ε-caprolactone)(PCL)-poly(2-vinyl)ethylene glycol(PVEG)copolymers bearing multi-pendant vinyl groups is synthesized by branched-selective allylic etherification polymerization of vinylethylene carbonate(VEC)with linear and tetra-arm PCLs under a synergistic catalysis of palladium complex and boron reagent.Facile thiol-ene photo-click reaction of PCL-PVEG copolymers with multifunctional thiols can rapidly access a serious crosslinked SMPs with high shape memory performance.The thermal properties,mechanical properties and response temperature of the obtained SMPs are tunable by the variation of PCL prepolymers,vinyl contents and functionality of thiols.Moreover,high elastic modulus in the rubbery plateau region can be maintained effectively owing to high-density topological networks of the PCL materials.In addition,the utility of the present SMPs is further demonstrated by the post-functionalization via thiol-ene photo-click chemistry.展开更多
The distribution of photo-crosslinkable moieties onto a protein backbone can affect a biomaterial’s crosslinking behavior, and therefore also its mechanical and biological properties. A profound insight in this respe...The distribution of photo-crosslinkable moieties onto a protein backbone can affect a biomaterial’s crosslinking behavior, and therefore also its mechanical and biological properties. A profound insight in this respect is essential for biomaterials exploited in tissue engineering and regenerative medicine. In the present work, photo-crosslinkable moieties have been introduced on the primary amine groups of: (i) a recombinant collagen peptide (RCPhC1) with a known amino acid (AA) sequence, and (ii) bovine skin collagen (COL BS) with an unknown AA sequence. The degree of substitution (DS) was quantified with two conventional techniques: an ortho-phthalic dialdehyde (OPA) assay and ^(1)H NMR spectroscopy. However, neither of both provides information on the exact type and location of the modified AAs. Therefore, for the first time, proteomic analysis was evaluated herein as a tool to identify functionalized AAs as well as the exact position of photo-crosslinkable moieties along the AA sequence, thereby enabling an in-depth, unprecedented characterization of functionalized photo-crosslinkable biopolymers. Moreover, our strategy enabled to visualize the spatial distribution of the modifications within the overall structure of the protein. Proteomics has proven to provide unprecedented insight in the distribution of photo-crosslinkable moieties along the protein backbone, undoubtedly contributing to superior functional biomaterial design to serve regenerative medicine.展开更多
Physiological repair of large-sized bone defects is great challenging in clinic due to a lack of ideal grafts suitable for bone regeneration.Decalcified bone matrix(DBM)is considered as an ideal bone regeneration scaf...Physiological repair of large-sized bone defects is great challenging in clinic due to a lack of ideal grafts suitable for bone regeneration.Decalcified bone matrix(DBM)is considered as an ideal bone regeneration scaffold,but low cell seeding efficiency and a poor osteoinductive microenvironment greatly restrict its application in large-sized bone regeneration.To address these problems,we proposed a novel strategy of bone regeneration units(BRUs)based on microgels produced by photo-crosslinkable and microfluidic techniques,containing both the osteogenic ingredient DBM and vascular endothelial growth factor(VEGF)for accurate biomimic of an osteoinductive microenvironment.The physicochemical properties of microgels could be precisely controlled and the microgels effectively promoted adhesion,proliferation,and osteogenic differentiation of bone marrow mesenchymal stem cells(BMSCs)in vitro.BRUs were successfully constructed by seeding BMSCs onto microgels,which achieved reliable bone regeneration in vivo.Finally,by integrating the advantages of BRUs in bone regeneration and the advantages of DBM scaffolds in 3D morphology and mechanical strength,a BRU-loaded DBM framework successfully regenerated bone tissue with the desired 3D morphology and effectively repaired a large-sized bone defect of rabbit tibia.The current study developed an ideal bone biomimetic microcarrier and provided a novel strategy for bone regeneration and large-sized bone defect repair.展开更多
Artificial sensory systems,designed to emulate human senses like sight,touch,and hearing,have garnered significant attention for their potential to enhance human capabilities,improve human-machine interactions,and ena...Artificial sensory systems,designed to emulate human senses like sight,touch,and hearing,have garnered significant attention for their potential to enhance human capabilities,improve human-machine interactions,and enable autonomous systems to better perceive their surroundings.Hydrogels,with their biocompatibility,flexibility,and water-rich polymer structure,are increasingly recognized as crucial materials in the development of these systems,especially in applications such as wearable sensors,artificial skin,and neural interfaces.This review explores various hydrogel fabrication techniques,including 3D bioprinting,electro spinning,and photopolymerization,which allow for the precise control of hydrogel properties like mechanical strength,flexibility,and conductivity.By tailoring these properties to mimic natural tissues,hydrogels offer transformative benefits in the creation of advanced,biocompatible,and durable sensory systems.We emphasize the importance of selecting appropriate fabrication methods to meet the specific functional requirements of artificial sensory applications,such as sensitivity to stimuli,durability,and ease of integration.This review further highlights the pivotal role of hydrogels in advancing future artificial sensory technologies and their broad potential in fields ranging from robotics to biomedical devices.展开更多
Crosslinking is one of the effective routes for improving the orientation stability of poled polymer films. The derivative of polyvinyl alcohol containing 4-nitro-4'-alkoxystilbene and photo-crosslinkable cinnamyl...Crosslinking is one of the effective routes for improving the orientation stability of poled polymer films. The derivative of polyvinyl alcohol containing 4-nitro-4'-alkoxystilbene and photo-crosslinkable cinnamyl groups as side chains has been synthesized. The in-situ simultaneous photo-crosslinking poling of synthesized polymer films has teen performed, The second order nonlinear optical coefficient d(33) of poled film is 11 pm/V. The SHG measurements show that the break-over temperature of SHG signal is raised obviously after irradiation, its orientation stability is doubled as compared with that of non-crosslinking samples.展开更多
The immature state of in vitro engineered cartilage(IVEC)hinders its clinical translation,highlighting the need for optimized scaffold platforms and cultivation models.Our previous work demonstrated that Wharton's...The immature state of in vitro engineered cartilage(IVEC)hinders its clinical translation,highlighting the need for optimized scaffold platforms and cultivation models.Our previous work demonstrated that Wharton's jelly(WJ)contains an extracellular matrix(ECM)whose composition closely resembles that of native cartilage and includes several bioactive factors that promote chondrogenic induction.Furthermore,earlier studies have shown that photo-crosslinkable hydrogels are ideal carrier scaffolds for cartilage tissue engineering and that bioreactors improve nutrient and waste exchange between scaffolds and the culture medium.Based on these findings,we employed a dynamic bioreactor in combination with a WJ-derived photocrosslinkable hydrogel to enhance IVEC maturity.Our results indicate that the decellularized WJ matrix(DWJM)effectively retains its native chondrogenic ECM components and bioactive factors.The photo-crosslinkable ADWJM hydrogel—produced by modifying DWJM with methacrylate anhydride—demonstrated excellent gelation capacity as well as tunable rheological properties,swelling ratios and degradation rates across different DWJM concentrations.In addition,the ADWJM hydrogel exhibited outstanding biocompatibility by providing a favorable 3D microenvironment for chondrocyte survival and proliferation.Most importantly,the dynamic bioreactor markedly promoted IVEC maturation.Constructs cultured under dynamic conditions displayed increased thickness,wet weight and volume;enhanced mechanical strength;more typical lacunae structures;and uniform deposition of cartilagespecific ECM compared to constructs maintained in static conditions or within a static bioreactor.Moreover,in vivo subcutaneous implantation of IVEC in goats further validated these findings,as the implanted constructs exhibited cartilage components and mechanical properties closely resembling those of natural cartilage.These results offer a promising approach for enhancing IVEC maturity and support its future clinical translation.展开更多
Emerging excessive greenhouse gas emissions pose great threats to the ecosystem,which thus requires efficient CO_(2)capture to mitigate the disastrous issue.In this report,large molecular size bisphenol A ethoxylate d...Emerging excessive greenhouse gas emissions pose great threats to the ecosystem,which thus requires efficient CO_(2)capture to mitigate the disastrous issue.In this report,large molecular size bisphenol A ethoxylate diacrylate(BPA)was employed to crosslink poly(ethylene glycol)methyl ether acrylate(PEGMEA)via the green and rapid UV polymerization strategy.The microstructure of such-prepared membrane could be conveniently tailored by tuning the ratio of the two prepolymers,aiming at obtaining the optimized microstructures with suitable mesh size and PEO sol content,which was approved by a novel low-field nuclear magnetic resonance technique.The optimum membrane overcomes the tradeoff challenge:dense microstructures lower the gas permeability while loose microstructures lower high-pressure-resistance capacity,realizing a high CO_(2)permeability of 1711 Barrer and 100-h long-term running stability under 15 atm.The proposed membrane fabrication approach,hence,opens a novel gate for developing high-performance robust membranes for CO_(2)capture.展开更多
Random copolyester of poly（ε-caprolactone-co-L-lactide） （PCLA） with a 50：50 feeding molar ratio was synthesized via the ring-opening polymerization and functionalized by the end-capping reaction with acryloyl ch...Random copolyester of poly（ε-caprolactone-co-L-lactide） （PCLA） with a 50：50 feeding molar ratio was synthesized via the ring-opening polymerization and functionalized by the end-capping reaction with acryloyl chloride. The resulting acrylated PCLA was then fabricated into small diameter tubular scaffolds by electrospinning technique and the formed scaffolds were followed by photocrosslinking under UV irradiation in the absence of photoinitiator. The mechanical strengths including tensile, suture retention and burst pressure were greatly enhanced after the photocrosslinking. The in vitro degradation data clearly revealed that the mechanical properties of the crosslinked scaffolds still remained after one month degradation in PBS solution, while those of the non-crosslinked ones lost heavily. The cytotoxicity assay on the mouse fibroblast L929 cells was conducted via MTT measurement. Furthermore, the observation on endothelial and fibroblast cell adhesion and proliferation was also made by using scanning electron microscopy （SEM）. The initiator-free photocrosslinked tubular scaffolds show the potential to be used in vascular tissue engineering.展开更多
Self-healing hydrogels with the shear-thinning property are novel injectable materials and are superior to traditional injectable hydrogels.The self-healing hydrogels based on 2-ureido-4[1 H]-pyrimidinone(UPy)have rec...Self-healing hydrogels with the shear-thinning property are novel injectable materials and are superior to traditional injectable hydrogels.The self-healing hydrogels based on 2-ureido-4[1 H]-pyrimidinone(UPy)have recently received extensive attention due to their dynamic reversibility of UPy dimerization.However,generally,UPy-based self-healing hydrogels exhibit poor stability,cannot degrade in vivo and can hardly be excreted from the body,which considerably limit their bio-application.Here,using poly(l-glutamic acid)(PLGA)as biodegradable matrix,branchingα-hydroxy-ω-amino poly(ethylene oxide)(HAPEO)as bridging molecule to introduce UPy,and ethyl acrylate polyethylene glycol(MAPEG)to introduce double bond,the hydrogel precursors(PMHU)are prepared.A library of the self-healing hydrogels has been achieved with well self-healable and shear-thinning properties.With the increase of MAPEG grafting ratio,the storage modulus of the self-healing hydrogels decreases.The self-healing hydrogels are stable in solution only for 6 h,hard to meet the requirements of tissue regeneration.Consequently,ultraviolet(UV)photo-crosslinking is involved to obtain the dual crosslinking hydrogels with enhanced mechanical properties and stability.When MAPEG grafting ratio is 35.5%,the dual crosslinking hydrogels can maintain the shape in phosphate-buffered saline solution(PBS)for at least 8 days.Loading with adipose-derived stem cell spheroids,the self-healing hydrogels are injected and self-heal to a whole,and then they are crosslinked in situ via UV-irradiation,obtaining the dual crosslinking hydrogels/cell spheroids complex with cell viability of 86.7%±6.0%,which demonstrates excellent injectability,subcutaneous gelatinization,and biocompatibility of hydrogels as cell carriers.The novel PMHU hydrogels crosslinked by quadruple hydrogen bonding and then dual photo-crosslinking of double bond are expected to be applied for minimal invasive surgery or therapies in tissue engineering.展开更多
The roles of reaction inhomogeneity in phase separation of polymer mixtures were described and summarized via two examples:photocross-link of polymer mixtures in the bulk state and photopolymerization of monomer in th...The roles of reaction inhomogeneity in phase separation of polymer mixtures were described and summarized via two examples:photocross-link of polymer mixtures in the bulk state and photopolymerization of monomer in the liquid state. The reaction kinetics,the reaction-induced elastic strain and the phase separation kinetics were monitored respectively by UV-Vis spectroscopy,Mach-Zehnder interferometry and laser-scanning confocal microscopy.It was found that phase separation in the bulk state was strongly inf...展开更多
Elastomeric scaffolds, individually customized to mimic the structural and mechanical properties of natural tissues have been used for tissue regeneration. In this regard, polyester elastic scaffolds with tunable mech...Elastomeric scaffolds, individually customized to mimic the structural and mechanical properties of natural tissues have been used for tissue regeneration. In this regard, polyester elastic scaffolds with tunable mechanical properties and exceptional biological properties have been reported to provide mechanical support and structural integrity for tissue repair. Herein, poly(4-methyl-ε-caprolactone) (PMCL) was first double-terminated by alkynylation (PMCL-DY) as a liquid precursor at room temperature. Subsequently, three-dimensional porous scaffolds with custom shapes were fabricated from PMCL-DY via thiol-yne photocrosslinking using a practical salt template method. By manipulating the Mn of the precursor, the modulus of compression of the scaffold was easily adjusted. As evidenced by the complete recovery from 90% compression, the rapid recovery rate of >500 mm min 1, the extremely low energy loss coefficient of <0.1, and the superior fatigue resistance, the PMCL20-DY porous scaffold was confirmed to harbor excellent elastic properties. In addition, the high resilience of the scaffold was confirmed to endow it with a minimally invasive application potential. In vitro testing revealed that the 3D porous scaffold was biocompatible with rat bone marrow stromal cells (BMSCs), inducing BMSCs to differentiate into chondrogenic cells. In addition, the elastic porous scaffold demonstrated good regenerative efficiency in a 12-week rabbit cartilage defect model. Thus, the novel polyester scaffold with adaptable mechanical properties may have extensive applications in soft tissue regeneration.展开更多
Facile and rapid 3D fabrication of strong,bioactive materials can address challenges that impede repair of large-to-massive rotator cuff tears including personalized grafts,limited mechanical support,and inadequate ti...Facile and rapid 3D fabrication of strong,bioactive materials can address challenges that impede repair of large-to-massive rotator cuff tears including personalized grafts,limited mechanical support,and inadequate tissue regeneration.Herein,we developed a facile and rapid methodology that generates visible light-crosslinkable polythiourethane(PHT)pre-polymer resin(~30 min at room temperature),yielding 3D-printable scaffolds with tendon-like mechanical attributes capable of delivering tenogenic bioactive factors.Ex vivo characterization confirmed successful fabrication,robust human supraspinatus tendon(SST)-like tensile properties(strength:23 MPa,modulus:459 MPa,at least 10,000 physiological loading cycles without failure),excellent suture retention(8.62-fold lower than acellular dermal matrix(ADM)-based clinical graft),slow degradation,and controlled release of fibroblast growth factor-2(FGF-2)and transforming growth factor-β3(TGF-β3).In vitro studies showed cytocompatibility and growth factor-mediated tenogenic-like differentiation of mesenchymal stem cells.In vivo studies demonstrated biocompatibility(3-week mouse subcutaneous implantation)and ability of growth factor-containing scaffolds to notably regenerate at least 1-cm of tendon with native-like biomechanical attributes as uninjured shoulder(8-week,large-to-massive 1-cm gap rabbit rotator cuff injury).This study demonstrates use of a 3D-printable,strong,and bioactive material to provide mechanical support and pro-regenerative cues for challenging injuries such as large-to-massive rotator cuff tears.展开更多
Collagen is a promising material for tissue engineering,but the poor mechanical properties of collagen hydrogels,which tend to cause contraction under the action of cellular activity,make its application challengeable...Collagen is a promising material for tissue engineering,but the poor mechanical properties of collagen hydrogels,which tend to cause contraction under the action of cellular activity,make its application challengeable.In this study,the amino group of type I collagen(Col I)was modified with methacrylic anhydride(MA)and the photo-crosslinkable methacrylate anhydride modified type I collagen(CM)with three different degrees of substitution(DS)was prepared.The physical properties of CM and Col I hydrogels were tested,including micromorphology,mechanical properties and degradation properties.The results showed that the storage modulus and degradation rate of hydrogels could be adjusted by changing the DS of CM.In vitro,chondrocytes were seeded into these four groups of hydrogels and subjected to fluorescein diacetate/propidium iodide(FDA/PI)staining,cell counting kit-8(CCK-8)test,histological staining and cartilage-related gene expression analysis.In vivo,these hydrogels encapsulating chondrocytes were implanted subcutaneously into nude mice,then histological staining and sulfated glycosaminoglycan(sGAG)/DNA assays were performed.The results demonstrated that contraction of hydrogels affected behaviors of chondrocytes,and CM hydrogels with suitable DS could resist contraction of hydrogels and promote the secretion of cartilage-specific matrix in vitro and in vivo.展开更多
Developmental engineering strategy needs the biomimetic composites that can integrate the progenitor cells,biomaterial matrices and bioactive signals to mimic the natural bone healing process for faster healing and re...Developmental engineering strategy needs the biomimetic composites that can integrate the progenitor cells,biomaterial matrices and bioactive signals to mimic the natural bone healing process for faster healing and reconstruction of segmental bone defects.We prepared the gelatin-reduced graphene oxide(GOG)and constructed the composites that mimicked the procallus by combining the GOG with the photo-crosslinked gelatin hydrogel.The biological effects of the GOG-reinforced composites could induce the bi-differentiation of bone marrow stromal cells(BMSCs)for rapid bone repair.The proper ratio of GOG in the composites regulated the composites’mechanical properties to a suitable range for the adhesion and proliferation of BMSCs.Besides,the GOG-mediated bidirectional differentiation of BMSCs,including osteogenesis and angiogenesis,could be activated through Erk1/2 and AKT pathway.The methyl vanillate(MV)delivered by GOG also contributed to the bioactive signals of the biomimetic procallus through priming the osteogenesis of BMSCs.During the repair of the calvarial defect in vivo,the initial hypoxic condition due to GOG in the composites gradually transformed into a well-vasculature robust situation with the bi-differentiation of BMSCs,which mimicked the process of bone healing resulting in the rapid bone regeneration.As an inorganic constituent,GOG reinforced the organic photo-crosslinked gelatin hydrogel to form a double-phase biomimetic procallus,which provided the porous extracellular matrix microenvironment and bioactive signals for the bi-directional differentiation of BMSCs.These show a promised application of the bio-reduced graphene oxide in biomedicine with a developmental engineering strategy.展开更多
Bioprinting has been a flouring way to fabricate complex tissue and organ mimics via precisely depositing printable cell-laden biomaterials.However,there is a limited number of biomaterials that fulfill the mechanical...Bioprinting has been a flouring way to fabricate complex tissue and organ mimics via precisely depositing printable cell-laden biomaterials.However,there is a limited number of biomaterials that fulfill the mechanical property of printing while meeting the responsive environment desired for the cells.Despite excellent cell compatibility and bioactivity,collagen suffers from difficulties in processing and printability which inhibited its utilization in three-dimensional(3D)bioprinting.Herein,we address this limitation by using ionic liquid as the solvent in the modification process,enabling collagens modified with quantified norbornene for chemical crosslink and extrusion-based 3D printing.With improved solubility and rheological properties,norbornene-functionalized collagen(Col-Nor)exhibited better shape fidelity in extrusion-based 3D printing compared with the one before modification.Photo-crosslinked Col-Nor hydrogel provided structural support and promoted the adhesion,proliferation,and differentiation of various types of cells,which afforded a centimeter-scale liver tissue model.This highly generalizable methodology expands printable,versatile,and tunable hydrogels developed from the natural extracellular matrix,allowing the biofabrication of 3D liver tissue model with branched vascular networks.展开更多
基金financially supported by the National Natural Science Foundation of China(No.22171182)Sichuan Tianfu Emei Plan.
文摘Control crosslink network and chain connectivity are essential to develop shape memory polymers(SMPs)with high shape memory capabilities,adjustable response temperature,and satisfying mechanistical properties.In this study,novel poly(ε-caprolactone)(PCL)-poly(2-vinyl)ethylene glycol(PVEG)copolymers bearing multi-pendant vinyl groups is synthesized by branched-selective allylic etherification polymerization of vinylethylene carbonate(VEC)with linear and tetra-arm PCLs under a synergistic catalysis of palladium complex and boron reagent.Facile thiol-ene photo-click reaction of PCL-PVEG copolymers with multifunctional thiols can rapidly access a serious crosslinked SMPs with high shape memory performance.The thermal properties,mechanical properties and response temperature of the obtained SMPs are tunable by the variation of PCL prepolymers,vinyl contents and functionality of thiols.Moreover,high elastic modulus in the rubbery plateau region can be maintained effectively owing to high-density topological networks of the PCL materials.In addition,the utility of the present SMPs is further demonstrated by the post-functionalization via thiol-ene photo-click chemistry.
基金The authors acknowledge the IBiSA network for financial support of the USR 3290(MSAP)proteomics facility TOP_OMICS.The mass spec-trometers were funded by the University of Lille,the CNRS,the Region Hauts-de-France and the European Regional Development Fund (ERDF).
文摘The distribution of photo-crosslinkable moieties onto a protein backbone can affect a biomaterial’s crosslinking behavior, and therefore also its mechanical and biological properties. A profound insight in this respect is essential for biomaterials exploited in tissue engineering and regenerative medicine. In the present work, photo-crosslinkable moieties have been introduced on the primary amine groups of: (i) a recombinant collagen peptide (RCPhC1) with a known amino acid (AA) sequence, and (ii) bovine skin collagen (COL BS) with an unknown AA sequence. The degree of substitution (DS) was quantified with two conventional techniques: an ortho-phthalic dialdehyde (OPA) assay and ^(1)H NMR spectroscopy. However, neither of both provides information on the exact type and location of the modified AAs. Therefore, for the first time, proteomic analysis was evaluated herein as a tool to identify functionalized AAs as well as the exact position of photo-crosslinkable moieties along the AA sequence, thereby enabling an in-depth, unprecedented characterization of functionalized photo-crosslinkable biopolymers. Moreover, our strategy enabled to visualize the spatial distribution of the modifications within the overall structure of the protein. Proteomics has proven to provide unprecedented insight in the distribution of photo-crosslinkable moieties along the protein backbone, undoubtedly contributing to superior functional biomaterial design to serve regenerative medicine.
基金financially supported by the National Key Research and Development Program of China(2017YFC1103900)the National Natural Science Foundation of China(81871502,81701843,and 81671837)+3 种基金the Shanghai Excellent Technical Leader(18XD1421500)the Program of Shanghai Academic/Technology Research Leader(19XD1431100)the Shanghai Collaborative Innovation Program on Regenerative Medicine and Stem Cell Research(2019CXJQ01)the Clinical Research Plan of SHDC(No.SHDC2020CR2045B).
文摘Physiological repair of large-sized bone defects is great challenging in clinic due to a lack of ideal grafts suitable for bone regeneration.Decalcified bone matrix(DBM)is considered as an ideal bone regeneration scaffold,but low cell seeding efficiency and a poor osteoinductive microenvironment greatly restrict its application in large-sized bone regeneration.To address these problems,we proposed a novel strategy of bone regeneration units(BRUs)based on microgels produced by photo-crosslinkable and microfluidic techniques,containing both the osteogenic ingredient DBM and vascular endothelial growth factor(VEGF)for accurate biomimic of an osteoinductive microenvironment.The physicochemical properties of microgels could be precisely controlled and the microgels effectively promoted adhesion,proliferation,and osteogenic differentiation of bone marrow mesenchymal stem cells(BMSCs)in vitro.BRUs were successfully constructed by seeding BMSCs onto microgels,which achieved reliable bone regeneration in vivo.Finally,by integrating the advantages of BRUs in bone regeneration and the advantages of DBM scaffolds in 3D morphology and mechanical strength,a BRU-loaded DBM framework successfully regenerated bone tissue with the desired 3D morphology and effectively repaired a large-sized bone defect of rabbit tibia.The current study developed an ideal bone biomimetic microcarrier and provided a novel strategy for bone regeneration and large-sized bone defect repair.
基金supported by the National Research Foundation of Korea(NRF)Grants funded by the Korea government(MSIT)(Nos.RS-2023-00213047 and RS-2024-00405818)。
文摘Artificial sensory systems,designed to emulate human senses like sight,touch,and hearing,have garnered significant attention for their potential to enhance human capabilities,improve human-machine interactions,and enable autonomous systems to better perceive their surroundings.Hydrogels,with their biocompatibility,flexibility,and water-rich polymer structure,are increasingly recognized as crucial materials in the development of these systems,especially in applications such as wearable sensors,artificial skin,and neural interfaces.This review explores various hydrogel fabrication techniques,including 3D bioprinting,electro spinning,and photopolymerization,which allow for the precise control of hydrogel properties like mechanical strength,flexibility,and conductivity.By tailoring these properties to mimic natural tissues,hydrogels offer transformative benefits in the creation of advanced,biocompatible,and durable sensory systems.We emphasize the importance of selecting appropriate fabrication methods to meet the specific functional requirements of artificial sensory applications,such as sensitivity to stimuli,durability,and ease of integration.This review further highlights the pivotal role of hydrogels in advancing future artificial sensory technologies and their broad potential in fields ranging from robotics to biomedical devices.
基金This work was supported by the National Natural Science Foundation of China
文摘Crosslinking is one of the effective routes for improving the orientation stability of poled polymer films. The derivative of polyvinyl alcohol containing 4-nitro-4'-alkoxystilbene and photo-crosslinkable cinnamyl groups as side chains has been synthesized. The in-situ simultaneous photo-crosslinking poling of synthesized polymer films has teen performed, The second order nonlinear optical coefficient d(33) of poled film is 11 pm/V. The SHG measurements show that the break-over temperature of SHG signal is raised obviously after irradiation, its orientation stability is doubled as compared with that of non-crosslinking samples.
基金supported by Hainan Province Clinical Medical Center,Hainan Provincial Natural Science Foundation(ZDYF2020130)Natural Science Foundation of China(82360560).
文摘The immature state of in vitro engineered cartilage(IVEC)hinders its clinical translation,highlighting the need for optimized scaffold platforms and cultivation models.Our previous work demonstrated that Wharton's jelly(WJ)contains an extracellular matrix(ECM)whose composition closely resembles that of native cartilage and includes several bioactive factors that promote chondrogenic induction.Furthermore,earlier studies have shown that photo-crosslinkable hydrogels are ideal carrier scaffolds for cartilage tissue engineering and that bioreactors improve nutrient and waste exchange between scaffolds and the culture medium.Based on these findings,we employed a dynamic bioreactor in combination with a WJ-derived photocrosslinkable hydrogel to enhance IVEC maturity.Our results indicate that the decellularized WJ matrix(DWJM)effectively retains its native chondrogenic ECM components and bioactive factors.The photo-crosslinkable ADWJM hydrogel—produced by modifying DWJM with methacrylate anhydride—demonstrated excellent gelation capacity as well as tunable rheological properties,swelling ratios and degradation rates across different DWJM concentrations.In addition,the ADWJM hydrogel exhibited outstanding biocompatibility by providing a favorable 3D microenvironment for chondrocyte survival and proliferation.Most importantly,the dynamic bioreactor markedly promoted IVEC maturation.Constructs cultured under dynamic conditions displayed increased thickness,wet weight and volume;enhanced mechanical strength;more typical lacunae structures;and uniform deposition of cartilagespecific ECM compared to constructs maintained in static conditions or within a static bioreactor.Moreover,in vivo subcutaneous implantation of IVEC in goats further validated these findings,as the implanted constructs exhibited cartilage components and mechanical properties closely resembling those of natural cartilage.These results offer a promising approach for enhancing IVEC maturity and support its future clinical translation.
基金This research was financially supported by National Natural Science Foundation of China(No.22125801,21975005,21878004)Cooperative Research Project of BJUT-NTUT(No.110-03).
文摘Emerging excessive greenhouse gas emissions pose great threats to the ecosystem,which thus requires efficient CO_(2)capture to mitigate the disastrous issue.In this report,large molecular size bisphenol A ethoxylate diacrylate(BPA)was employed to crosslink poly(ethylene glycol)methyl ether acrylate(PEGMEA)via the green and rapid UV polymerization strategy.The microstructure of such-prepared membrane could be conveniently tailored by tuning the ratio of the two prepolymers,aiming at obtaining the optimized microstructures with suitable mesh size and PEO sol content,which was approved by a novel low-field nuclear magnetic resonance technique.The optimum membrane overcomes the tradeoff challenge:dense microstructures lower the gas permeability while loose microstructures lower high-pressure-resistance capacity,realizing a high CO_(2)permeability of 1711 Barrer and 100-h long-term running stability under 15 atm.The proposed membrane fabrication approach,hence,opens a novel gate for developing high-performance robust membranes for CO_(2)capture.
基金supported by the‘863' Project of Minister of Science and Technology of China(Nos.2006AA02A134 and 2007AA021905)basic research foundation of Beijing Institute of Technology(No. 20080942001).
文摘Random copolyester of poly（ε-caprolactone-co-L-lactide） （PCLA） with a 50：50 feeding molar ratio was synthesized via the ring-opening polymerization and functionalized by the end-capping reaction with acryloyl chloride. The resulting acrylated PCLA was then fabricated into small diameter tubular scaffolds by electrospinning technique and the formed scaffolds were followed by photocrosslinking under UV irradiation in the absence of photoinitiator. The mechanical strengths including tensile, suture retention and burst pressure were greatly enhanced after the photocrosslinking. The in vitro degradation data clearly revealed that the mechanical properties of the crosslinked scaffolds still remained after one month degradation in PBS solution, while those of the non-crosslinked ones lost heavily. The cytotoxicity assay on the mouse fibroblast L929 cells was conducted via MTT measurement. Furthermore, the observation on endothelial and fibroblast cell adhesion and proliferation was also made by using scanning electron microscopy （SEM）. The initiator-free photocrosslinked tubular scaffolds show the potential to be used in vascular tissue engineering.
基金financially supported by the National Natural Science Foundation of China(No.51773113)。
文摘Self-healing hydrogels with the shear-thinning property are novel injectable materials and are superior to traditional injectable hydrogels.The self-healing hydrogels based on 2-ureido-4[1 H]-pyrimidinone(UPy)have recently received extensive attention due to their dynamic reversibility of UPy dimerization.However,generally,UPy-based self-healing hydrogels exhibit poor stability,cannot degrade in vivo and can hardly be excreted from the body,which considerably limit their bio-application.Here,using poly(l-glutamic acid)(PLGA)as biodegradable matrix,branchingα-hydroxy-ω-amino poly(ethylene oxide)(HAPEO)as bridging molecule to introduce UPy,and ethyl acrylate polyethylene glycol(MAPEG)to introduce double bond,the hydrogel precursors(PMHU)are prepared.A library of the self-healing hydrogels has been achieved with well self-healable and shear-thinning properties.With the increase of MAPEG grafting ratio,the storage modulus of the self-healing hydrogels decreases.The self-healing hydrogels are stable in solution only for 6 h,hard to meet the requirements of tissue regeneration.Consequently,ultraviolet(UV)photo-crosslinking is involved to obtain the dual crosslinking hydrogels with enhanced mechanical properties and stability.When MAPEG grafting ratio is 35.5%,the dual crosslinking hydrogels can maintain the shape in phosphate-buffered saline solution(PBS)for at least 8 days.Loading with adipose-derived stem cell spheroids,the self-healing hydrogels are injected and self-heal to a whole,and then they are crosslinked in situ via UV-irradiation,obtaining the dual crosslinking hydrogels/cell spheroids complex with cell viability of 86.7%±6.0%,which demonstrates excellent injectability,subcutaneous gelatinization,and biocompatibility of hydrogels as cell carriers.The novel PMHU hydrogels crosslinked by quadruple hydrogen bonding and then dual photo-crosslinking of double bond are expected to be applied for minimal invasive surgery or therapies in tissue engineering.
基金supported by the Ministry of Education (MONKASHO),Japan through the Grant-in-Aid on the Priority-Research-Area"Molecular Nanodynamics"and"Soft Matter Physics".The Grant-in-Aid for Scientific Research (No.20350107) is also gratefully acknowledged.
文摘The roles of reaction inhomogeneity in phase separation of polymer mixtures were described and summarized via two examples:photocross-link of polymer mixtures in the bulk state and photopolymerization of monomer in the liquid state. The reaction kinetics,the reaction-induced elastic strain and the phase separation kinetics were monitored respectively by UV-Vis spectroscopy,Mach-Zehnder interferometry and laser-scanning confocal microscopy.It was found that phase separation in the bulk state was strongly inf...
基金support by the National Key Research and Development Program(2021YFB3800800)the National Natural Science Foundation of China(52273009)+1 种基金the National Natural Science Foundation of China(82271038)the Interdisciplinary Program of Shanghai JiaoTong University(YG2022QN050).
文摘Elastomeric scaffolds, individually customized to mimic the structural and mechanical properties of natural tissues have been used for tissue regeneration. In this regard, polyester elastic scaffolds with tunable mechanical properties and exceptional biological properties have been reported to provide mechanical support and structural integrity for tissue repair. Herein, poly(4-methyl-ε-caprolactone) (PMCL) was first double-terminated by alkynylation (PMCL-DY) as a liquid precursor at room temperature. Subsequently, three-dimensional porous scaffolds with custom shapes were fabricated from PMCL-DY via thiol-yne photocrosslinking using a practical salt template method. By manipulating the Mn of the precursor, the modulus of compression of the scaffold was easily adjusted. As evidenced by the complete recovery from 90% compression, the rapid recovery rate of >500 mm min 1, the extremely low energy loss coefficient of <0.1, and the superior fatigue resistance, the PMCL20-DY porous scaffold was confirmed to harbor excellent elastic properties. In addition, the high resilience of the scaffold was confirmed to endow it with a minimally invasive application potential. In vitro testing revealed that the 3D porous scaffold was biocompatible with rat bone marrow stromal cells (BMSCs), inducing BMSCs to differentiate into chondrogenic cells. In addition, the elastic porous scaffold demonstrated good regenerative efficiency in a 12-week rabbit cartilage defect model. Thus, the novel polyester scaffold with adaptable mechanical properties may have extensive applications in soft tissue regeneration.
基金supported by Hong Kong Health Bureau (DFEK:Health Medical and Research Fund,08190466,DMW:Health Medical and Research Fund,07180686)Hong Kong Research Grants Council (DFEK:Early Career Scheme Award,24201720,General Research Fund:14213922,DMW:General Research Fund:14118620 and 14121121)+3 种基金National Natural Science Foundation of China-Hong Kong Research Grants Council Joint Research Scheme (DMW:N_CUHK409/23)Hong Kong Innovation and Technology Commission (DFEK:Tier 3 Award,ITS/090/18,DW:ITS/333/18DFEK,DMW,and RST:Health@InnoHK program)The Chinese University of Hong Kong (DFEK:Faculty Innovation Award,FIA2018/A/01)。
文摘Facile and rapid 3D fabrication of strong,bioactive materials can address challenges that impede repair of large-to-massive rotator cuff tears including personalized grafts,limited mechanical support,and inadequate tissue regeneration.Herein,we developed a facile and rapid methodology that generates visible light-crosslinkable polythiourethane(PHT)pre-polymer resin(~30 min at room temperature),yielding 3D-printable scaffolds with tendon-like mechanical attributes capable of delivering tenogenic bioactive factors.Ex vivo characterization confirmed successful fabrication,robust human supraspinatus tendon(SST)-like tensile properties(strength:23 MPa,modulus:459 MPa,at least 10,000 physiological loading cycles without failure),excellent suture retention(8.62-fold lower than acellular dermal matrix(ADM)-based clinical graft),slow degradation,and controlled release of fibroblast growth factor-2(FGF-2)and transforming growth factor-β3(TGF-β3).In vitro studies showed cytocompatibility and growth factor-mediated tenogenic-like differentiation of mesenchymal stem cells.In vivo studies demonstrated biocompatibility(3-week mouse subcutaneous implantation)and ability of growth factor-containing scaffolds to notably regenerate at least 1-cm of tendon with native-like biomechanical attributes as uninjured shoulder(8-week,large-to-massive 1-cm gap rabbit rotator cuff injury).This study demonstrates use of a 3D-printable,strong,and bioactive material to provide mechanical support and pro-regenerative cues for challenging injuries such as large-to-massive rotator cuff tears.
基金This work was sponsored by the National Key Research and Development Program of China(2019YFA0110600)Science and Technology Support Program of Sichuan Province(2019YJ0161)Guangxi Key Research and Development Plan(GuikeAB16450003).
文摘Collagen is a promising material for tissue engineering,but the poor mechanical properties of collagen hydrogels,which tend to cause contraction under the action of cellular activity,make its application challengeable.In this study,the amino group of type I collagen(Col I)was modified with methacrylic anhydride(MA)and the photo-crosslinkable methacrylate anhydride modified type I collagen(CM)with three different degrees of substitution(DS)was prepared.The physical properties of CM and Col I hydrogels were tested,including micromorphology,mechanical properties and degradation properties.The results showed that the storage modulus and degradation rate of hydrogels could be adjusted by changing the DS of CM.In vitro,chondrocytes were seeded into these four groups of hydrogels and subjected to fluorescein diacetate/propidium iodide(FDA/PI)staining,cell counting kit-8(CCK-8)test,histological staining and cartilage-related gene expression analysis.In vivo,these hydrogels encapsulating chondrocytes were implanted subcutaneously into nude mice,then histological staining and sulfated glycosaminoglycan(sGAG)/DNA assays were performed.The results demonstrated that contraction of hydrogels affected behaviors of chondrocytes,and CM hydrogels with suitable DS could resist contraction of hydrogels and promote the secretion of cartilage-specific matrix in vitro and in vivo.
基金This study was supported by the National Natural Science Foundation of China(51703127,31600777,81620108006,81901048,81801006,81991505)the National Key Research and Development Program of China(2016YFC1102900)+1 种基金Innovative research team of high-level local universities in Shanghai(SSMU-ZDCX20180900)Young Elite Scientist Sponsorship Program by CAST(2017QNRC001).
文摘Developmental engineering strategy needs the biomimetic composites that can integrate the progenitor cells,biomaterial matrices and bioactive signals to mimic the natural bone healing process for faster healing and reconstruction of segmental bone defects.We prepared the gelatin-reduced graphene oxide(GOG)and constructed the composites that mimicked the procallus by combining the GOG with the photo-crosslinked gelatin hydrogel.The biological effects of the GOG-reinforced composites could induce the bi-differentiation of bone marrow stromal cells(BMSCs)for rapid bone repair.The proper ratio of GOG in the composites regulated the composites’mechanical properties to a suitable range for the adhesion and proliferation of BMSCs.Besides,the GOG-mediated bidirectional differentiation of BMSCs,including osteogenesis and angiogenesis,could be activated through Erk1/2 and AKT pathway.The methyl vanillate(MV)delivered by GOG also contributed to the bioactive signals of the biomimetic procallus through priming the osteogenesis of BMSCs.During the repair of the calvarial defect in vivo,the initial hypoxic condition due to GOG in the composites gradually transformed into a well-vasculature robust situation with the bi-differentiation of BMSCs,which mimicked the process of bone healing resulting in the rapid bone regeneration.As an inorganic constituent,GOG reinforced the organic photo-crosslinked gelatin hydrogel to form a double-phase biomimetic procallus,which provided the porous extracellular matrix microenvironment and bioactive signals for the bi-directional differentiation of BMSCs.These show a promised application of the bio-reduced graphene oxide in biomedicine with a developmental engineering strategy.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA16020804,XDA16020802)the National Natural Science Foundation of China(22021002,22022705)。
文摘Bioprinting has been a flouring way to fabricate complex tissue and organ mimics via precisely depositing printable cell-laden biomaterials.However,there is a limited number of biomaterials that fulfill the mechanical property of printing while meeting the responsive environment desired for the cells.Despite excellent cell compatibility and bioactivity,collagen suffers from difficulties in processing and printability which inhibited its utilization in three-dimensional(3D)bioprinting.Herein,we address this limitation by using ionic liquid as the solvent in the modification process,enabling collagens modified with quantified norbornene for chemical crosslink and extrusion-based 3D printing.With improved solubility and rheological properties,norbornene-functionalized collagen(Col-Nor)exhibited better shape fidelity in extrusion-based 3D printing compared with the one before modification.Photo-crosslinked Col-Nor hydrogel provided structural support and promoted the adhesion,proliferation,and differentiation of various types of cells,which afforded a centimeter-scale liver tissue model.This highly generalizable methodology expands printable,versatile,and tunable hydrogels developed from the natural extracellular matrix,allowing the biofabrication of 3D liver tissue model with branched vascular networks.
