Chitin is a kind of natural macromolecule material which was first discovered in mushrooms and was widely found in the shells of crustaceans and arthropods,the cell walls of fungi(yeast and mold)and algae,and the moll...Chitin is a kind of natural macromolecule material which was first discovered in mushrooms and was widely found in the shells of crustaceans and arthropods,the cell walls of fungi(yeast and mold)and algae,and the mollusks.The original chitin in nature usually has an antiparallel molecular chain alignment forming nanofibers connected by inter-and intramolecular hydrogen bonds.These microfibers consist of nanofibers about 2-5 nm in diameter,and about 300 nm long,embedded by protein matrices.Due to their unique dimensional,optical,mechanical,and other characteristics,the preparation of nano-chitin materials is an important subject.It is possible to extract nano-chitins from their sources with various methods,including acid hydrolysis,mechanical disintegration,TEMPO-mediated oxidation,electrospinning,and others.In this article,the latest progress in recent years in the preparation and applications of nano-chitin were reviewed.The morphology of the nano-chitins obtained from the above methods was presented.The advantages and disadvantages of each method were analyzed.An overview of applications of nano-chitins was discussed,including biomedicine,food applications,water treatment,green electronic materials,enzyme immobilization carriers,cotton textile materials,cosmetics,and others.展开更多
Studies on food supply values,the basis of eco-service values,and their factors of different pond aquaculture ecosystems are helpful to explain the influences of the inputted factors and their variations among these e...Studies on food supply values,the basis of eco-service values,and their factors of different pond aquaculture ecosystems are helpful to explain the influences of the inputted factors and their variations among these ecosystems and provide information for stakeholders to adjust their decisions and behaviors to increase their total eco-service values. On the basis of continued records from 2011 to 2012 of 18 ponds of three pond aquaculture ecosystems,namely Litopenaeus vannamei,Macrobrachium nippponensis and carp fresh water pond aquaculture ecosystems in Qingpu,Fengxian,and Jiading,three suburban districts of Shang,this paper analyzed the costs,returns,net food supply values and their regional and temporal fluctuations. The results showed that:(1) the net food supply values of the three ecosystems are 143252. 4,135883. 7,and 52623. 1Yuan /Ha in 2011 correspondently,with the Litopenaeus vannamei pond aquaculture ecosystem(LVPAE) ranking highest and the carp pond aquaculture ecosystem(CPAE) lowest among them,and the trend was same in 2012,but the values decreased than that of 2011 with the rate of 30. 0%( LVPAE),38. 0 %( Macrobrachium nippponensis pond aquaculture ecosystem,MNPAE) and 13. 7 %( CPAE).(2)The dominant factors of the net food supply values of these ecosystems are the produce price and variable costs; fry and feed costs are the main variable factors producing the noticeable difference among the ecosystems.(3) The cost- benefit ratio of per unit product of the CPAE,LVPAE and MNPAE changed from 27. 5%,91. 7%,129. 0% in 2011 to 23. 0%,73. 8% and 63. 8% in 2012,with the CPAE ranked lowest among them in both years.(4) For all the three ecosystems,their net food supply values may not always change in same trends with their net eco-service values,if stakeholders want to keep a balance between these two types of values,MNPAE should be encouraged in these districts.展开更多
Among various electrocatalysts,high entropy materials(HEMs)have attracted great attention due to the distinctive designing concept and unique properties with captivating electrocatalytic activity and stability.To date...Among various electrocatalysts,high entropy materials(HEMs)have attracted great attention due to the distinctive designing concept and unique properties with captivating electrocatalytic activity and stability.To date,HEMs have been a new family of advanced electrocatalysts in the research field of water electrolysis.In this work,the structural features and synthesis strategies of high entropy catalysts are reviewed,especially,their performances for catalyzing hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)in water electrolysis are presented,in which the crucial roles of structure,composition,multisites synergy,and“four core effects”for enhancing catalytic activity,stability,and resistance of electrochemical corrosion are introduced.Besides,the design tactics,main challenges,and future prospects of HEM-based electrocatalysts for HER and OER are discussed.It is expected to provide valuable information for the development of low-cost efficient HEM-based electrocatalysts in the field of water electrolysis.展开更多
Porous nanofiber-microsphere mats of collagen （COL）/polyvinyl alcohol （PVA） containing salicylic acid （SA） as model drug were prepared by electrospirming for the assessment of drug delivery system. The electrosp...Porous nanofiber-microsphere mats of collagen （COL）/polyvinyl alcohol （PVA） containing salicylic acid （SA） as model drug were prepared by electrospirming for the assessment of drug delivery system. The electrospun fibrous mats were crosslinked by UV-radiation or glutaraldehyde to weaken the degree of drug burst release and morphology damage when meeting water. The morphology and chemical structures of COL/PVA-SA electrospun fibers were characterized by SEM and FTIR. The crosslinking of UV-radiation did not destroy the morphology of COL/PVA-SA electrospun fibers in the crosslinking process, however, the crosslinking of glutaraldehyde did it. In vitro release studies showed that COL/PVA-SA electrospun fibers efficiently controlled the release of drugs by the crosslinking of UV-radiation for 4 h. The transport mechanism that controlled the release of drugs from electrospun mats was Fickian diffusion.展开更多
Thermal degradation of vegetable-tanned leather fiber(VLF)was investigated by thermogravimetric analysis aiming to know the exact kinetics and degradation mechanism.The thermogravimetric(TG)and differential thermograv...Thermal degradation of vegetable-tanned leather fiber(VLF)was investigated by thermogravimetric analysis aiming to know the exact kinetics and degradation mechanism.The thermogravimetric(TG)and differential thermogravimetric(DTG)curves showed that decomposition of the VLF occurs mainly in the range of 150-600℃,and the latter exhibits asymmetrical peak with a pronounced shoulder.The decomposition process was first analyzed by deconvolution of the experimental DTG curves,followed by reconstruction of the weight loss profiles of two individual processes.Several common isoconversional approaches were applied to calculate the activation energy over a wide range of conversion for the sample,including modified Kissinger-Akahira-Sunose(MKAS),Friedman,and Flynn-Wall-Ozawa.The average activation energy of vegetable-tanned leather fiber was found to be 241.9 kJ mol^(−1) by MKAS method.The activation energy values obtained for the pseudocomponents representing highly-crosslinked and low-crosslinked collagen in VLF were given as 190.6 and 124.8 kJ mol^(−1),respectively.Generalized master plots results suggested that the reaction mechanism for highly-crosslinked collagen follows the random nucleation and growth process at conversion values lower than 0.5.When the conversion is higher than 0.5,the mechanism tends to random scission model.For low-crosslinked collagen,the degradation is mainly governed by random nucleation and nuclei growth.The gaseous products of VLF thermal degradation were analyzed with an online-coupled TG-Fourier transform infrared spectroscopy system.展开更多
Chrome shavings(CS),a kind of solid wastes discharged from tanneries,always pose serious environmental problems due to the presence of chromium.In this work,kinetic study of the pyrolysis of CS was investigated using ...Chrome shavings(CS),a kind of solid wastes discharged from tanneries,always pose serious environmental problems due to the presence of chromium.In this work,kinetic study of the pyrolysis of CS was investigated using a thermogravimetric analyzer in nitrogen atmosphere.The results obtained from the thermogravimetric analysis indicated that there are three stages in the temperature range 25 to 600℃.The second stage is the main weight loss stage and it could be mainly attributed to the pyrolysis of collagenous materials.Iso-conversional and generalized master-plots method were first employed to estimate the activation energy value and possible reaction mechanism of CS pyrolysis.The results showed that the pyrolysis process could not be described accurately by single-step reaction due to the heterogeneous nature of CS.Afterwards,the thermogravimetric kinetic of CS pyrolysis was studied using combined kinetic analysis.It was found that three-parallel-reaction model allowed better fitting relevance for CS pyrolysis.This information was important for simulating and predicting the pyrolysis behaviors of CS.展开更多
Leather is a collagen-based biomass prepared from raw skins or hides by a series of unit operations, in which the unhairing and fiber opening are extremely important operations. However, the conventional Na2S/Ca(OH)2 ...Leather is a collagen-based biomass prepared from raw skins or hides by a series of unit operations, in which the unhairing and fiber opening are extremely important operations. However, the conventional Na2S/Ca(OH)2 system used in unhairing and fiber opening has given rise to the pollution to the environment. It is necessary to develop substitute technology for the Na2S/Ca(OH)2. In the present study, 1-allyl-3-methylimidazolium chloride ([AMIm]Cl) was used to cooperate with dispase for cycle unhairing and one-pot beamhouse to recycle waste bovine hides and com-pared with conventional processing. During those processes, the mechanism of [AMIm]Cl-dispase synergistic unhair-ing and collagen fibers opening were studied. Besides, plant hazard, organic matter and [AMIm]Cl of wastewater from [AMIm]Cl-dispase process were respectively investigated and separated to evaluate the environmental and economic benefits of the [AMIm]Cl-dispase process. As a result, enzyme activity after unhairing by [AMIm]Cl-diapase system for using 5 times is higher than that by KCl-dispase system, and needs lower unhairing time, which is because of rapid penetration of [AMIm]Cl-dispase solution in bovine hides. For this reason, the tensile strength and elastic modulus of tanned leather from [AMIm]Cl-dispase process are higher than those from the KCl-diapase and conventional pro-cesses, and its hydrothermal shrinkage temperature is comparable to that of the conventional one. Because of the 58.13% lower wastewater discharge (WD), 66.60% lower total solids (TS), 97.23% lower ammonia nitrogen (NH3-N), non-toxic wastewater and organic matter recovery in wastewater are reached from [AMIm]Cl-dispase process, which is expected to be an alternative to the conventional process to reduce environmental pollution and realize the sustainable development of technology for leather manufacturing.展开更多
Introduction of vacancies is a promising route to enhance the performance of electrocatalysts by tuning the electronic structure and bonding energy.Here,the influence of ultrasound treatment on the O vacancies formati...Introduction of vacancies is a promising route to enhance the performance of electrocatalysts by tuning the electronic structure and bonding energy.Here,the influence of ultrasound treatment on the O vacancies formation and interlayer spacing in NiFe layered double hydroxide(LDH)was investigated.It is found that the strong ultrasound treatment results in rich O vacancies on the surface of NiFe LDH,which affect the electrocatalysis performance.Besides,the ultrasound treated NiFe LDH electrocatalysts had a reduced thickness with a hexagonal nanosheet morphology and expanded interlayer distance,which could promote the diffusion of reactant and generated gas.When the obtained defect-rich NiFe LDH electrocatalyst prepared by a 10-min ultrasonic treatment was applied to catalyze oxygen evolution reaction(OER),only 194 mV of overpotential was needed to maintain a current density of 10 mA⋅cm^(-2).展开更多
Soybean can serve as an efficient carbon and nitrogen source for in-situ fabrication of efficient composite electrocatalysts with conductive nitrogen-doped carbon(N-C)material.In this study,the iron-doped cobalt nitri...Soybean can serve as an efficient carbon and nitrogen source for in-situ fabrication of efficient composite electrocatalysts with conductive nitrogen-doped carbon(N-C)material.In this study,the iron-doped cobalt nitride/phosphide(Fe-Co_(3)N/CoP)nanosheet was composited with a conductive N-C material by using soybean as C and N source,as well as NH3 as additional nitrogen source.During the nitridation process of Fe-Co_(3)N,N-C bond was formed as a newly generated Co(Fe)-N-C active sites.Therefore,it fabricates a good microscopic contact interface between the catalyst and carbon material for charge transfer.Besides,the introduction of Fe-CoP by partially phosphating Fe-Co_(3)N further improved the OER activity due to the high catalytic activity of Co sites with high valence state.As a result,the obtained electrocatalyst exhibited overpotentials as low as 285 and 390 mV for supporting 10 and 100 mA/cm2 current densities.This work indicates that the design of materials with good interfaces could be an effective approach for the preparation of electrocatalysts for water electrolysis.展开更多
Collagen with a multi-hierarchical architecture exhibits powerful biological performance,thus being developed in biomedical applications as a processing building block.The isolated collagen after extraction from biolo...Collagen with a multi-hierarchical architecture exhibits powerful biological performance,thus being developed in biomedical applications as a processing building block.The isolated collagen after extraction from biological tissues can be processed into various forms such as fibrils,scaffolds,membranes,microspheres,hydrogels,and sponges for further use in specific applications.This review briefly discusses the multi-hierarchical structure,powerful biological performances,extraction,and processing approaches of collagen as a natural biomaterial.The processing of collagen including dissolution,self-assembly,cross-linking,and electrospinning,is discussed to show more feasibility for specific applications of collagen composite biomaterials.Further emphasis is directed towards the biomedical applications of drug and gene delivery,as well as tissue repair involving bone,cartilage,vascular,and corneal,along with wound healing.Additionally,there is a focus on the development of flexible sensors and electronic skins(e-skins).Furthermore,the potential challenges and perspectives for the development of collagen-based biomaterials are proposed.In short,collagen-based biomaterials are expected to facilitate sustainable development and the next generation of advanced biomaterial applications.展开更多
基金supported by the National Natural Science Foundation of China[51473150,51603191,U1404509]sthe Education Department of Henan Province[17HASTIT009]
文摘Chitin is a kind of natural macromolecule material which was first discovered in mushrooms and was widely found in the shells of crustaceans and arthropods,the cell walls of fungi(yeast and mold)and algae,and the mollusks.The original chitin in nature usually has an antiparallel molecular chain alignment forming nanofibers connected by inter-and intramolecular hydrogen bonds.These microfibers consist of nanofibers about 2-5 nm in diameter,and about 300 nm long,embedded by protein matrices.Due to their unique dimensional,optical,mechanical,and other characteristics,the preparation of nano-chitin materials is an important subject.It is possible to extract nano-chitins from their sources with various methods,including acid hydrolysis,mechanical disintegration,TEMPO-mediated oxidation,electrospinning,and others.In this article,the latest progress in recent years in the preparation and applications of nano-chitin were reviewed.The morphology of the nano-chitins obtained from the above methods was presented.The advantages and disadvantages of each method were analyzed.An overview of applications of nano-chitins was discussed,including biomedicine,food applications,water treatment,green electronic materials,enzyme immobilization carriers,cotton textile materials,cosmetics,and others.
基金Supported by the Natural Science Foundation of China(70973075)Research and Innovation Project of Shanghai Municipal Education Commission(09ZZ169)
文摘Studies on food supply values,the basis of eco-service values,and their factors of different pond aquaculture ecosystems are helpful to explain the influences of the inputted factors and their variations among these ecosystems and provide information for stakeholders to adjust their decisions and behaviors to increase their total eco-service values. On the basis of continued records from 2011 to 2012 of 18 ponds of three pond aquaculture ecosystems,namely Litopenaeus vannamei,Macrobrachium nippponensis and carp fresh water pond aquaculture ecosystems in Qingpu,Fengxian,and Jiading,three suburban districts of Shang,this paper analyzed the costs,returns,net food supply values and their regional and temporal fluctuations. The results showed that:(1) the net food supply values of the three ecosystems are 143252. 4,135883. 7,and 52623. 1Yuan /Ha in 2011 correspondently,with the Litopenaeus vannamei pond aquaculture ecosystem(LVPAE) ranking highest and the carp pond aquaculture ecosystem(CPAE) lowest among them,and the trend was same in 2012,but the values decreased than that of 2011 with the rate of 30. 0%( LVPAE),38. 0 %( Macrobrachium nippponensis pond aquaculture ecosystem,MNPAE) and 13. 7 %( CPAE).(2)The dominant factors of the net food supply values of these ecosystems are the produce price and variable costs; fry and feed costs are the main variable factors producing the noticeable difference among the ecosystems.(3) The cost- benefit ratio of per unit product of the CPAE,LVPAE and MNPAE changed from 27. 5%,91. 7%,129. 0% in 2011 to 23. 0%,73. 8% and 63. 8% in 2012,with the CPAE ranked lowest among them in both years.(4) For all the three ecosystems,their net food supply values may not always change in same trends with their net eco-service values,if stakeholders want to keep a balance between these two types of values,MNPAE should be encouraged in these districts.
基金supported by Natural Science Foundation of Henan Province(NO.202300410433)ZiQoo Chemical Co.Ltd,Japan.We also appreciate Mr Lijie Hou of the Shiyanjia Lab(www.shiyanjia.com)for providing the supporting materials.
文摘Among various electrocatalysts,high entropy materials(HEMs)have attracted great attention due to the distinctive designing concept and unique properties with captivating electrocatalytic activity and stability.To date,HEMs have been a new family of advanced electrocatalysts in the research field of water electrolysis.In this work,the structural features and synthesis strategies of high entropy catalysts are reviewed,especially,their performances for catalyzing hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)in water electrolysis are presented,in which the crucial roles of structure,composition,multisites synergy,and“four core effects”for enhancing catalytic activity,stability,and resistance of electrochemical corrosion are introduced.Besides,the design tactics,main challenges,and future prospects of HEM-based electrocatalysts for HER and OER are discussed.It is expected to provide valuable information for the development of low-cost efficient HEM-based electrocatalysts in the field of water electrolysis.
文摘Porous nanofiber-microsphere mats of collagen （COL）/polyvinyl alcohol （PVA） containing salicylic acid （SA） as model drug were prepared by electrospirming for the assessment of drug delivery system. The electrospun fibrous mats were crosslinked by UV-radiation or glutaraldehyde to weaken the degree of drug burst release and morphology damage when meeting water. The morphology and chemical structures of COL/PVA-SA electrospun fibers were characterized by SEM and FTIR. The crosslinking of UV-radiation did not destroy the morphology of COL/PVA-SA electrospun fibers in the crosslinking process, however, the crosslinking of glutaraldehyde did it. In vitro release studies showed that COL/PVA-SA electrospun fibers efficiently controlled the release of drugs by the crosslinking of UV-radiation for 4 h. The transport mechanism that controlled the release of drugs from electrospun mats was Fickian diffusion.
基金National Key Research and Development Program(2017YFB0308500)National Natural Science Foundation Commission of China(51673177,U1204504)Science and Technology Project of Henan Province(172102410022).
文摘Thermal degradation of vegetable-tanned leather fiber(VLF)was investigated by thermogravimetric analysis aiming to know the exact kinetics and degradation mechanism.The thermogravimetric(TG)and differential thermogravimetric(DTG)curves showed that decomposition of the VLF occurs mainly in the range of 150-600℃,and the latter exhibits asymmetrical peak with a pronounced shoulder.The decomposition process was first analyzed by deconvolution of the experimental DTG curves,followed by reconstruction of the weight loss profiles of two individual processes.Several common isoconversional approaches were applied to calculate the activation energy over a wide range of conversion for the sample,including modified Kissinger-Akahira-Sunose(MKAS),Friedman,and Flynn-Wall-Ozawa.The average activation energy of vegetable-tanned leather fiber was found to be 241.9 kJ mol^(−1) by MKAS method.The activation energy values obtained for the pseudocomponents representing highly-crosslinked and low-crosslinked collagen in VLF were given as 190.6 and 124.8 kJ mol^(−1),respectively.Generalized master plots results suggested that the reaction mechanism for highly-crosslinked collagen follows the random nucleation and growth process at conversion values lower than 0.5.When the conversion is higher than 0.5,the mechanism tends to random scission model.For low-crosslinked collagen,the degradation is mainly governed by random nucleation and nuclei growth.The gaseous products of VLF thermal degradation were analyzed with an online-coupled TG-Fourier transform infrared spectroscopy system.
基金the Key Scientific Research Projects of Henan Province,China[grant number 21A430034]National Key R&D Program of China[grant number 2017YFB0308500].
文摘Chrome shavings(CS),a kind of solid wastes discharged from tanneries,always pose serious environmental problems due to the presence of chromium.In this work,kinetic study of the pyrolysis of CS was investigated using a thermogravimetric analyzer in nitrogen atmosphere.The results obtained from the thermogravimetric analysis indicated that there are three stages in the temperature range 25 to 600℃.The second stage is the main weight loss stage and it could be mainly attributed to the pyrolysis of collagenous materials.Iso-conversional and generalized master-plots method were first employed to estimate the activation energy value and possible reaction mechanism of CS pyrolysis.The results showed that the pyrolysis process could not be described accurately by single-step reaction due to the heterogeneous nature of CS.Afterwards,the thermogravimetric kinetic of CS pyrolysis was studied using combined kinetic analysis.It was found that three-parallel-reaction model allowed better fitting relevance for CS pyrolysis.This information was important for simulating and predicting the pyrolysis behaviors of CS.
基金National Natural Science Foundation of China(No.51673177)National Key R&D Program of China(No.2017YFB0308500).
文摘Leather is a collagen-based biomass prepared from raw skins or hides by a series of unit operations, in which the unhairing and fiber opening are extremely important operations. However, the conventional Na2S/Ca(OH)2 system used in unhairing and fiber opening has given rise to the pollution to the environment. It is necessary to develop substitute technology for the Na2S/Ca(OH)2. In the present study, 1-allyl-3-methylimidazolium chloride ([AMIm]Cl) was used to cooperate with dispase for cycle unhairing and one-pot beamhouse to recycle waste bovine hides and com-pared with conventional processing. During those processes, the mechanism of [AMIm]Cl-dispase synergistic unhair-ing and collagen fibers opening were studied. Besides, plant hazard, organic matter and [AMIm]Cl of wastewater from [AMIm]Cl-dispase process were respectively investigated and separated to evaluate the environmental and economic benefits of the [AMIm]Cl-dispase process. As a result, enzyme activity after unhairing by [AMIm]Cl-diapase system for using 5 times is higher than that by KCl-dispase system, and needs lower unhairing time, which is because of rapid penetration of [AMIm]Cl-dispase solution in bovine hides. For this reason, the tensile strength and elastic modulus of tanned leather from [AMIm]Cl-dispase process are higher than those from the KCl-diapase and conventional pro-cesses, and its hydrothermal shrinkage temperature is comparable to that of the conventional one. Because of the 58.13% lower wastewater discharge (WD), 66.60% lower total solids (TS), 97.23% lower ammonia nitrogen (NH3-N), non-toxic wastewater and organic matter recovery in wastewater are reached from [AMIm]Cl-dispase process, which is expected to be an alternative to the conventional process to reduce environmental pollution and realize the sustainable development of technology for leather manufacturing.
基金financial supports from the Natural Science Foundation of Henan Province(NO.202300410433)the Scientific Research Foundation of Zhengzhou University(32210862,32211241).
文摘Introduction of vacancies is a promising route to enhance the performance of electrocatalysts by tuning the electronic structure and bonding energy.Here,the influence of ultrasound treatment on the O vacancies formation and interlayer spacing in NiFe layered double hydroxide(LDH)was investigated.It is found that the strong ultrasound treatment results in rich O vacancies on the surface of NiFe LDH,which affect the electrocatalysis performance.Besides,the ultrasound treated NiFe LDH electrocatalysts had a reduced thickness with a hexagonal nanosheet morphology and expanded interlayer distance,which could promote the diffusion of reactant and generated gas.When the obtained defect-rich NiFe LDH electrocatalyst prepared by a 10-min ultrasonic treatment was applied to catalyze oxygen evolution reaction(OER),only 194 mV of overpotential was needed to maintain a current density of 10 mA⋅cm^(-2).
基金The financial supports from the Natural Science Foundation of Henan Province(NO.202300410433)the Scientific Research Foundation of Zhengzhou University(2021cxcy566)are greatly appreciated.
文摘Soybean can serve as an efficient carbon and nitrogen source for in-situ fabrication of efficient composite electrocatalysts with conductive nitrogen-doped carbon(N-C)material.In this study,the iron-doped cobalt nitride/phosphide(Fe-Co_(3)N/CoP)nanosheet was composited with a conductive N-C material by using soybean as C and N source,as well as NH3 as additional nitrogen source.During the nitridation process of Fe-Co_(3)N,N-C bond was formed as a newly generated Co(Fe)-N-C active sites.Therefore,it fabricates a good microscopic contact interface between the catalyst and carbon material for charge transfer.Besides,the introduction of Fe-CoP by partially phosphating Fe-Co_(3)N further improved the OER activity due to the high catalytic activity of Co sites with high valence state.As a result,the obtained electrocatalyst exhibited overpotentials as low as 285 and 390 mV for supporting 10 and 100 mA/cm2 current densities.This work indicates that the design of materials with good interfaces could be an effective approach for the preparation of electrocatalysts for water electrolysis.
基金supported by the National Natural Science Foundation of China(52073262).
文摘Collagen with a multi-hierarchical architecture exhibits powerful biological performance,thus being developed in biomedical applications as a processing building block.The isolated collagen after extraction from biological tissues can be processed into various forms such as fibrils,scaffolds,membranes,microspheres,hydrogels,and sponges for further use in specific applications.This review briefly discusses the multi-hierarchical structure,powerful biological performances,extraction,and processing approaches of collagen as a natural biomaterial.The processing of collagen including dissolution,self-assembly,cross-linking,and electrospinning,is discussed to show more feasibility for specific applications of collagen composite biomaterials.Further emphasis is directed towards the biomedical applications of drug and gene delivery,as well as tissue repair involving bone,cartilage,vascular,and corneal,along with wound healing.Additionally,there is a focus on the development of flexible sensors and electronic skins(e-skins).Furthermore,the potential challenges and perspectives for the development of collagen-based biomaterials are proposed.In short,collagen-based biomaterials are expected to facilitate sustainable development and the next generation of advanced biomaterial applications.
