The focus of drug delivery is shifting toward smart drug carriers that release the cargo in response to a change in the microenvironment due to an internal or external trigger. As the most clinically successful nanosy...The focus of drug delivery is shifting toward smart drug carriers that release the cargo in response to a change in the microenvironment due to an internal or external trigger. As the most clinically successful nanosystem, liposomes naturally come under the spotlight of this trend. This review summarizes the latest development about the design and construction of photo-responsive liposomes with gold nanoparticles for the controlled drug release. Alongside, we overview the mechanism involved in this process and the representative applications.展开更多
Dimension-controllable supramolecular organic frameworks(SOFs)with aggregation-enhanced fluorescence are hierarchically fabricated through the host-vip interactions of cucurbit[8]uril(CB[8])and coumarin-modified tet...Dimension-controllable supramolecular organic frameworks(SOFs)with aggregation-enhanced fluorescence are hierarchically fabricated through the host-vip interactions of cucurbit[8]uril(CB[8])and coumarin-modified tetraphenylethylene derivatives(TPEC).The three-dimensional layered SOFs could be constructed from the further stacking of two-dimensional mono-layered structures via simply regulating the self-assembly conditions including the culturing time and concentration.Upon light irradiation under the wavelength of 365 nm,the photodimerization of coumarin moieties occurred,which resulted in the transformation of the resultant TPECn/CB[8]4n two-dimensional SOFs into robust covalently-connected 2D polymers with molecular thickness.Interestingly,the supramolecular system of TPEC/CB[8]exhibited intriguing multicolor fluorescence emission from yellow to blue in the time range of 0-24 h at 365 nm irradiation,possessing potential applicability for photochromic fluorescence ink.展开更多
Photo-responsive slippery lubricant-infused porous surface(SLIPS) for droplet manipulation is flexible, noncontact and non-destructive in droplet manipulation, which has promising applications in flexible robotics, mi...Photo-responsive slippery lubricant-infused porous surface(SLIPS) for droplet manipulation is flexible, noncontact and non-destructive in droplet manipulation, which has promising applications in flexible robotics, microfluidics,biomedicine, and chemical analysis. However, the repeated manipulations for droplets of SLIPSs are quite limited in the works reported so far, the poor durability of droplet manipulation severely limits the practical application of the surfaces. In this paper, an Fe3O4-doped polydimethylsiloxane(PDMS)-based SLIPS is proposed and implemented to achieve ultra-high repeated droplet manipulation numbers under near-infrared ray(NIR) laser irradiation. Firstly, a micron columnar array structure with micro-pits on the top side, as well as, a wall structure out of the array is designed on SLIPS to reserve the lubricant. Secondly, the prototype of the SLIPS is fabricated by a 3-step ultraviolet(UV) lithography, and subsequently immersed in silicone oil for more than 96 h to obtain the ultra-high durability slippery lubricant-infused porous surface(UD-SLIPS). With a power of 25 m W–85 m W NIR laser, the repeated manipulation of microdroplets(≤ 5 μL) in the scale of 1 cm can exceed more than 3000 times which is far beyond that in previous reports. Finally, the droplet manipulation performance of this photo-responsive UD-SLIPS and the influence of infusion time on durability are investigated. The mechanism of the PDMS swelling effect is found to be the key factor in improving the droplet manipulation durability of SLIPS. The findings of this work would be of great significance for the development of highly durable photo-responsive functional surfaces for droplet manipulation.展开更多
Developing hydroscopic actuators with simultaneous high elasticity,shape programmability and tunable actuating behaviors are highly desired but still challenging.In this study,we propose an orthogonal composite design...Developing hydroscopic actuators with simultaneous high elasticity,shape programmability and tunable actuating behaviors are highly desired but still challenging.In this study,we propose an orthogonal composite design to develop such a material.The developed composite elastomer comprises carboxyl group-grafted polystyrene-block-poly(ethylene-co-butylene)-block-polystyrene(SEBS-g-COOH)as the elastic substrate,and a synthesized azobenzene derivative as the functional filler(Azo12).By surface treatment using acidic and base solutions,the carboxyl groups on the surface can reversibly transform into carboxylate groups,which render the composite tunable hygroscopic actuating functionality.On another aspect,the added filler undergoes trans-to-cis isomerization when exposed to UV light irradiation,leading to liquefaction of the crystalline aggregates formed by Azo12 molecules.The liquefied Azo12 molecules can autonomously resotre their trans form and reform the crystalline structure.This reversible change in crystralline structure is utilized to realize the shape memory property,and 5 wt%of Azo12addition is adequate for the composite to exhibit photo-responsive shape memory behavior without compromising much of the elasricity.The regualtion of external geometry by shape memory effect is effective in altering the actuating behavior.The proposed method can be extend to designing different composites with the demonstrated functionalities.展开更多
Cell migration in three-dimensional environment is extremely important for tissue regeneration and other biological processes.In this work,a model system was developed to study how endothelial cells(ECs)migrate into p...Cell migration in three-dimensional environment is extremely important for tissue regeneration and other biological processes.In this work,a model system was developed to study how endothelial cells(ECs)migrate into photo-responsive hydrogels under the presence of pro-inflammatory macrophages.The hydrogel was synthesized from hyaluronic acid grafted with coumarin and methacrylate moieties by both carbon–carbon covalent linking and coumarin dimerization under UV irradiation at 365 nm.The structure of the hydrogel was conveniently modulated by UV irradiation at 254nm to decompose the coumarin dimers,leading to the significant decrease of modulus and increase of swelling ratio and mesh size.Under the presence of M1 macrophages,ECs were induced to migrate into the hydrogels with a different degree.A significant larger net displacement of ECs was found in the softer hydrogel obtained by irradiation with UV at 254nm than in the stiffer original one at day 7.展开更多
Photo-responsive polymer materials from zero-dimensional micelles, two-dimensional surfaces to three-dimensional hydrogels have been designed, synthesized and applied for various biological fields including drug deliv...Photo-responsive polymer materials from zero-dimensional micelles, two-dimensional surfaces to three-dimensional hydrogels have been designed, synthesized and applied for various biological fields including drug delivery and cell manipulation. Many remarkable works have been reported, revealing the advantages of photo-responsive polymers such as noninvasion and spatiotemporal control. In this review, we briefly summarized the remarkable progress of photo-responsive polymers with irreversible or reversible moieties and their further biological applications. The future opportunities and challenges of photo-responsive polymer materials are also proposed.展开更多
The conformation-dependent activity of azo-benzene combretastatin A4(Azo-CA4)provides a unique approach to reduce the side-effects of chemotherapy,due to the light-triggered conformation transition of its azobenzene m...The conformation-dependent activity of azo-benzene combretastatin A4(Azo-CA4)provides a unique approach to reduce the side-effects of chemotherapy,due to the light-triggered conformation transition of its azobenzene moiety.Under hypoxic tumor microenviron-ment,however,the high expression of azoreductase can reduce azobenzene to aniline.It was postulated that the Azo-CA4 might be degraded under hypoxia,resulting in the decrease of its anti-tumor activity.The aim of this study was to verify such hypothesis in HeLa cells in vitro.The quantitative drug concentration analysis shows the ratio-metric formation of degradation end-products,confirming the bioreduction of Azo-CA4.The tubulin staining study indicates that Azo-CA4 loses the potency of switching off microtubule dynamics under hypoxia.Furthermore,the cell cycle analysis shows that the ability of Azo-CA4 to induce mitotic arrest is lost at low oxygen content.Therefore,the cytotoxicity of Azo-CA4 is compromised under hypoxia.In contrast,combretastatin A4 as a positive control maintains the potency to inhibit tubulin polymer-ization and break down the nuclei irrespective of light irradiation and oxygen level.This work highlights the influence of hypoxic tumor microenvironment on the anti-tumor potency of Azo-CA4,which should be considered during the early stage of designing translational Azo-CA4 delivery systems.展开更多
Glutathione peroxidase (GPx) is a vital antioxidant enzyme involved in the reduction of reactive oxygen species and protects cells from oxidative damage.Consequently enormous efforts have been devoted to developing ar...Glutathione peroxidase (GPx) is a vital antioxidant enzyme involved in the reduction of reactive oxygen species and protects cells from oxidative damage.Consequently enormous efforts have been devoted to developing artificial catalysts with GPx function.Besides the research on enhancing the catalytic activity of GPx mimics,the design and construction of smart GPx models has also inspired great interest.Herein,a novel photo-responsive seleniumcontaining vesicular GPx model was successfully constructed by supramolecular self-assembly of the cationic surfactant PyC10AZoC10Py with benzeneseleninic acid (PhSeO2H) through hydrophobic and electrostatic interactions in aqueous media.This selenium-containing vesicular catalyst showed remarkable GPx-like activity,which is 692times more effective than PhSeO2H for the reduction of cumene hydroperoxide (CUOOH) by 4-nitrobenzenethiol (NBT).Interestingly,when an equimolar amount of α-CD was added,the GPx-like activity of the catalytic vesicle declines remarkably due to the vesicle disaggregation in the presence ofα-CD.Whereas the biomimetic system was irradiated by UV light at 365 nm,the catalytic vesicle was formed again and the GPx-like activity recovered.展开更多
Stimuli-responsive macrocycles are of importance for synthetic chemistry and smart materials. In this manuscript, we report two novel organoborane cyclophanes, which were successfully synthesized by ruthenium-catalyze...Stimuli-responsive macrocycles are of importance for synthetic chemistry and smart materials. In this manuscript, we report two novel organoborane cyclophanes, which were successfully synthesized by ruthenium-catalyzed olefin metathesis. They are composed of one/two boron-doped helicene π-skeletons and flexible alkyl chain linkers, thus representing a new kind of non-conjugated organoborane macrocycles. Their cyclic structures and photophysical properties, as well as Lewis acidity were theoretically and experimentally investigated. Notably, two enantiomers in one single crystal are observed for one organoborane cyclophane, owning to the presence of helical π-framework in its cyclic structure. Moreover, their Lewis acid-base adducts may dissociate in the excited state and thus display intriguing photo-responsive fluorescence properties, which can be further modulated by temperature. This study thus provides a novel design strategy for non-conjugated organoborane macrocycles, which may promote the development of stimuli-responsive macrocyclic materials with fascinating properties.展开更多
Direct alcohol fuel cells(DAFCs)have received wide attention as a new type of clean energy device because of their high energy conversion efficiency,portability,non-toxicity and pollution-free.Anode catalysts are the ...Direct alcohol fuel cells(DAFCs)have received wide attention as a new type of clean energy device because of their high energy conversion efficiency,portability,non-toxicity and pollution-free.Anode catalysts are the key factors affecting the performance of DAFCs.Recently studies show that using the optical activity of semiconductor materials as the carriers of traditional precious metal electrocatalysts,under the illumination of light sources,can greatly improve the electrocatalytic activity and stability of electrodes.In this review,the research progress of photo-responsive metal/semiconductor hybrids as the electrocatalysts for DAFCs in recent years is summarized,including:(1)Mechanism and advantages of photo-assistant electrochemical alcohol oxidation reaction,(2)me tal/semiconductor electrocatalyst for the different type of fuel cell reactions,(3)different kind of metals in photo-responsive metal/semiconductor hybrid nanostructure,(4)the personal prospects of the photo-responsive metal/semiconductor electrode for future application in DAFCs.展开更多
The exploration of novel photo/thermal-responsive nonvolatile memorizers will be beneficial for energysaving memories.Herein,new<110>-oriented perovskites using single template melamine,i.e.,[(MLAI-H_(2))(PbX_(4...The exploration of novel photo/thermal-responsive nonvolatile memorizers will be beneficial for energysaving memories.Herein,new<110>-oriented perovskites using single template melamine,i.e.,[(MLAI-H_(2))(PbX_(4))]_n(X=Br (α-1),Cl (α-2),MLAI=melamine) have been prepared and their structures upon irradiation of visible light have been investigated.They have been fabricated as nonvolatile memory devices with structures of ITO/[(MLAI-H_(2))(PbX_(4))]_n/PMMA/Ag (device-1:X=Br,device-2:X=Cl),which can exhibit unique visible light-triggered binary nonvolatile memory performances.Interestingly,the silent or working status can be monitored by visible chromisms.Furthermore,the light-triggered binary resistive switching mechanisms of these ITO/[(MLAI-H_(2))(PbX_(4))]_n/PMMA/Ag memory devices have been clarified in terms of EPR,fluorescence,and single-crystal structural analysis.The presence of light-activated traps in<110>-oriented[(MLAI-H_(2))(PbX_(4))]_n perovskites are dominated in the appearance of light-triggered resistive switching behaviors,based on which the inverted internal electrical fields can be established.According to the structural analysis,the more distorted PbX_6octahedra,higher corrugated<110>-oriented perovskite sheets,and more condensed organic-inorganic packing in Br-containing perovskite are beneficial for the stabilization of light-activated traps,which lead to the better resistive switching behavior of device-1.This work can pave a new avenue for the establishment of novel energy-saving nonvolatile memorizers used in aerospace or military industries.展开更多
Ultraviolet light(UV)is an essential component of ambient light,but high dose UV would damage genome DNA.While semiconductors and soft materials have been employed to detect the UV,the complex process and the instrume...Ultraviolet light(UV)is an essential component of ambient light,but high dose UV would damage genome DNA.While semiconductors and soft materials have been employed to detect the UV,the complex process and the instrumental requirement have limited the application in daily life.In this study,taking advantage of sequence designability,a series of hydrogels with different gel-sol transition rates was constructed under the same UV intensity by introducing competing hybridization to tune the stability of the molecular network.Through estimating the transition time between each system under UV light irradiation,the intensity of UV could be roughly estimated,which provided a convenient method for the visual detection of UV.展开更多
The research of photo-responsive materials,with changed absorption and emission under light stimulus,has drawn more and more attention due to their wide applications.However,most of them suffered from the notorious ag...The research of photo-responsive materials,with changed absorption and emission under light stimulus,has drawn more and more attention due to their wide applications.However,most of them suffered from the notorious aggregation-caused quenching(ACQ)effect,which often led to the unconspicuous luminescent change in photo-responsive process.To solve this problem,the strategy of combining aggregation-induced emission(AIE)and photochromic properties was utilized,which largely enriched the phenomenon and application of photo-responsive materials.This short review summarized the recent progress of photo-responsive AIE materials with changed UV absorbance or PL phenomenon under UV-irradiation,including the types of molecular structures,internal mechanisms and the practical applications.Also,some outlooks were given on the further exploration of this field at the end of this paper.展开更多
Photo-responsive mechanical actuator is a class of stimuli-responsive materials transferring light to mechanical energy through macroscopic transformation.To fabricate photo-responsive mechanical actuator,soft polymer...Photo-responsive mechanical actuator is a class of stimuli-responsive materials transferring light to mechanical energy through macroscopic transformation.To fabricate photo-responsive mechanical actuator,soft polymeric materials crosslinked with functional bridging structures are desired.Supramolecular interaction is a relatively common way to fabricate crosslinked materials due to its excellent self-assembly performance.And azobenzene and derivatives are ideal candidates of photo-responsive materials because of the unique photo-induced trans-cis isomerization.Here,a new kind of crosslinked materials based on supramolecular interaction between 4,4'-dihydroxyazobenzene and chitosan is reported.Under 355 nm irradiation,the macroscopic bending of polymeric materials occurs rapidly due to the photo-isomerization of 4,4-dihydroxyazobenzene.Meanwhile,the photo-responsive mechanical actuator can also lift weight which is up to 200 times that of the actuator itself,and convert energy from light to mechanical work efficiently.This report suggests a new kind of photo-responsive actuator based on supramolecular interaction and may be helpful to contribute a theoretical basis to the design and synthesis of photo-responsive mechanical actuator suitable for large-scale manufacturing industrialization in future.展开更多
Solid-stated smart polymers responsive to external stimuli have attracted much attention for potential application in the field of photoelectron devices,logic gates,sensor,data storage and security.However,it is a big...Solid-stated smart polymers responsive to external stimuli have attracted much attention for potential application in the field of photoelectron devices,logic gates,sensor,data storage and security.However,it is a bigger challenge for polymers than that for small molecules in solid state to acquire stimuli-responsive properties,because polymers with high molecular weight are not as easy to change the packing structure as small molecules under external stimulation.Here,a D-A type alternating copolymer PTMF-o containing 3,4-bisthienylmaleimide(A unit)and fluorene(D unit)is designed and synthesized.Upon irradiation of sunlight,PTMF-o film exhibits a photo-response with the color altering from purple to colorless.It is attributed to the structure of copolymer transformed from ring-opening form(PTMF-o)to ring-closure form(PTMF-c),resulting from the oxidative photocyclization of 3,4-bisthienylmaleimide unit.Consequently,the ability of charge transfer(CT)from fluorene to 3,4-bisthienylmaleimide unit in PTMF-o can be easily weakened by light stimuli.PTMF-o film displays a WORM-type resistive storage performance for the strong CT.Interestingly,after exposure,the electrical memory behavior in situ transfers into FLASH type,due to weak CT in PTMF-c.PTMF-o film can also be employed as smart material to construct NAND and NOR logic gates by using light as input condition.The work provides a simple way to modify the electronic properties of polymers and realize stimuli-response in solid states.展开更多
We investigated the feasibility of obtaining large photoresponse in metal-semiconductor-metal(MSM) type single nanowire device where one contact can be blocking type. We showed that suitable modification of the blocki...We investigated the feasibility of obtaining large photoresponse in metal-semiconductor-metal(MSM) type single nanowire device where one contact can be blocking type. We showed that suitable modification of the blocking contact by deposition of a capping metal using focused electron beam(FEB) can lead to considerable enhancement of the photoresponse. The work was done in a single Cu:TCNQ nanowire device fabricated by direct growth of nanowires(NW) from pre-patterned Cu electrode which makes the contact ohmic with the other contact made from Au. Analysis of the data shows that the large photoresponse of the devices arises predominantly due to reduction of the barriers at the Au/NW blocking contact on illumination. This is caused by the diffusion of the photo generated carriers from the nanowires to the contact region. When the barrier height is further reduced by treating the contact with FEB deposited Pt, this results in a large enhancement in the device photoresponse.展开更多
The smart emulsification and demulsification system with the light response is a useful tool in various industries,including green chemistry,catalytic reaction,pharmaceuticals,and environmental remediation.Herein,an i...The smart emulsification and demulsification system with the light response is a useful tool in various industries,including green chemistry,catalytic reaction,pharmaceuticals,and environmental remediation.Herein,an ionic liquid crystal compound with a light triggered switch based on the azobenzene group[(4-{3-methyl-1-[3-(8-octyloxyoctyl)oxy-4-oxobutanoyl]imidazo-lium-1-yl}octyl)oxy]-N-(4-methylphenyl)benzene-1,2-diazene bromide(MOIAzo),was designed and synthesized,which could cause reversible transition between emulsification and demulsification through the light trigger.The ionic liquid has an efficient photoinduced liquefaction process,which dramatically lowers the melting point of ionic liquids from 79 to 9.2 oC.This significantly broadens the liquid state temperature of the ionic liquid crystal.The ionic liquid crystal MOIAzo exhibits both photoinduced and thermally induced nematic liquid crystal properties.The smart emulsion system was effectively employed in an eco-friendly water-saving dyeing process of cationic dyes for cationic dyeable polyester(CDP)fabrics,which used only half the amount of water compared with the conventional water bath dyeing method.After dyeing,the oil and water phases can be efficiently separated through the light irradiation,and the oil phase can be reused for the subsequent dyeing process.This novel smart emulsion dyeing method greatly reduces the water consumption and wastewater discharge.MOIAzo as a lighttriggered ionic liquid molecule opens up new dimensions in green chemistry.展开更多
A three-transistor active pixel sensor and its double sampling readout circuit implemented by a switch capacitor amplifier are designed. The circuit is embedded in a 64 × 64 pixel array CMOS image sensor and succ...A three-transistor active pixel sensor and its double sampling readout circuit implemented by a switch capacitor amplifier are designed. The circuit is embedded in a 64 × 64 pixel array CMOS image sensor and success-fully taped out with a Chartered 0.35μm process. The pixel pitch is 8μm × 8μm with a fill factor of 57%, the photo-sensitivity is 0.8V/（lux · s） ,and the dynamic range is 50dB. Theoretical analysis and test results indicate that as the process is scaled down, a smaller pixel pitch reduces the sensitivity. A deep junction n-well/p-substrate photodiode with a reasonable fill factor and high sensitivity are more appropriate for submicron processes.展开更多
[Objective] This study compared the leaf photosynthetic characteristics of Turpan grape cultivated in greenhouses and open field to provide a scientific basis for the high-quality and high-yield cultivation of grape. ...[Objective] This study compared the leaf photosynthetic characteristics of Turpan grape cultivated in greenhouses and open field to provide a scientific basis for the high-quality and high-yield cultivation of grape. [Method] Two precocious grape varieties as experimental materials were cultivated in greenhouses and open field, and their net photosynthetic rates （Pn）, photo-response curves and CO2 response curves were determined using Li-400XT portable photosynthesis system. [Result] The leaf Pn of the two varieties cultivated in open field was higher than that in greenhouse. The Pn of Hongqitezao cultivated in open field was the highest, up to 19.79 μmol/（m^2·s）; in the photo-response curves, Hongqitezao cultivated in greenhouse had the largest Pnmax and apparent quantum yield （AQY）, while the Flame Seedless in greenhouse had the smallest light compensation point （LCP）. The light saturation point （LSP） value of greenhouse cultivation was higher than that of open field cultivation. In the CO2 response test, the dark respiration rate （Rd） and Pnmax of greenhouse cultivation were higher than those of open field cultivation, and the carboxylation efficiency （CE） of greenhouse cultivation was lower than that of open field cultivation; the CO2 compensation point （CCP） and CO2 saturation point （CSP） of greenhouse cultivation were lower than those of open field cultivation. [Conclusion] The utilization of elevated light in greenhouse cultivation was more efficient than in open field cultivation; however, the utilization of elevated CO2 in greenhouse cultivation was weaker than tin open field cultivation.展开更多
It is an urgent task to develop highly efficient non-noble metal electrocatalysts in the direction of ORR,but still a huge and long-term challenge.Herein,an efficient one-step pyrolysis of Sichuan pepper powder,2,2-bi...It is an urgent task to develop highly efficient non-noble metal electrocatalysts in the direction of ORR,but still a huge and long-term challenge.Herein,an efficient one-step pyrolysis of Sichuan pepper powder,2,2-bipyridine,FeCl3,Na SCN,and ZnCl2 at 900℃ provides the FeS/ZnS@N,S-C-900 hybrid catalyst.Transmission electron microscopy(TEM)images and Mott-Schottky curves clearly reveal the in-situ constructed abundant FeS/ZnS-based p-n junctions dispersed on the biomass-derived porous carbon surface of FeS/ZnS@N,S-C-900.The as-prepared FeS/ZnS@N,S-C-900 hybrid exhibits superior ORR performance in comparison with Pt/C in 0.1 M KOH with high onset(Eonset)and half-wave potentials(E1/2)of 1.00 and 0.880 V vs.RHE,large limiting current density(JL)of 5.60 mA cm-2,and robust durability and methanol tolerance.Impressively,upon the light irradiation,FeS/ZnS@N,S-C-900 produces a photocurrent as high as ca.0.3μA cm-2,resulting in further improvement over Eonset,E1/2,and JLof FeS/ZnS@N,S-C-900 to1.10 V vs.RHE,0.885 V vs.RHE,and 6.02 mA cm-2.Experiment in combination with theoretical calculations demonstrate the significant effect of FeS/ZnS heterojunction on the enhanced ORR catalytic activity of FeS/ZnS@N,S-C-900.This work is useful for the development of advanced heterojunction-based ORR catalysts for various energy conversion devices.展开更多
文摘The focus of drug delivery is shifting toward smart drug carriers that release the cargo in response to a change in the microenvironment due to an internal or external trigger. As the most clinically successful nanosystem, liposomes naturally come under the spotlight of this trend. This review summarizes the latest development about the design and construction of photo-responsive liposomes with gold nanoparticles for the controlled drug release. Alongside, we overview the mechanism involved in this process and the representative applications.
基金supported by Anhui Province Natural Science Funds(2008085QE209)K2020-03 from the State Key Laboratory of Molecular Engineering of Polymers(Hehai University)。
文摘Dimension-controllable supramolecular organic frameworks(SOFs)with aggregation-enhanced fluorescence are hierarchically fabricated through the host-vip interactions of cucurbit[8]uril(CB[8])and coumarin-modified tetraphenylethylene derivatives(TPEC).The three-dimensional layered SOFs could be constructed from the further stacking of two-dimensional mono-layered structures via simply regulating the self-assembly conditions including the culturing time and concentration.Upon light irradiation under the wavelength of 365 nm,the photodimerization of coumarin moieties occurred,which resulted in the transformation of the resultant TPECn/CB[8]4n two-dimensional SOFs into robust covalently-connected 2D polymers with molecular thickness.Interestingly,the supramolecular system of TPEC/CB[8]exhibited intriguing multicolor fluorescence emission from yellow to blue in the time range of 0-24 h at 365 nm irradiation,possessing potential applicability for photochromic fluorescence ink.
基金Project supported by the National Major Scientific Research Instrument Development Project of China (Grant No. 51927804)the National Natural Science Foundation of China (Grant No. 62275216)the Science and Technology Innovation Team Project of Shaanxi Province (Grant Nos. S2018-ZC-TD-0061 and 2023-CX-TD-06)。
文摘Photo-responsive slippery lubricant-infused porous surface(SLIPS) for droplet manipulation is flexible, noncontact and non-destructive in droplet manipulation, which has promising applications in flexible robotics, microfluidics,biomedicine, and chemical analysis. However, the repeated manipulations for droplets of SLIPSs are quite limited in the works reported so far, the poor durability of droplet manipulation severely limits the practical application of the surfaces. In this paper, an Fe3O4-doped polydimethylsiloxane(PDMS)-based SLIPS is proposed and implemented to achieve ultra-high repeated droplet manipulation numbers under near-infrared ray(NIR) laser irradiation. Firstly, a micron columnar array structure with micro-pits on the top side, as well as, a wall structure out of the array is designed on SLIPS to reserve the lubricant. Secondly, the prototype of the SLIPS is fabricated by a 3-step ultraviolet(UV) lithography, and subsequently immersed in silicone oil for more than 96 h to obtain the ultra-high durability slippery lubricant-infused porous surface(UD-SLIPS). With a power of 25 m W–85 m W NIR laser, the repeated manipulation of microdroplets(≤ 5 μL) in the scale of 1 cm can exceed more than 3000 times which is far beyond that in previous reports. Finally, the droplet manipulation performance of this photo-responsive UD-SLIPS and the influence of infusion time on durability are investigated. The mechanism of the PDMS swelling effect is found to be the key factor in improving the droplet manipulation durability of SLIPS. The findings of this work would be of great significance for the development of highly durable photo-responsive functional surfaces for droplet manipulation.
基金financially supported by the National Natural Science Foundation of China(Nos.51803115 and 21636006)the Fundamental Research Funds for the Central Universities(Nos.GK201901001,2021CSLY008,2021CSZL003 and GK202103032)the Innovation Capability Support Program of Shaanxi(No.2020TD-024)。
文摘Developing hydroscopic actuators with simultaneous high elasticity,shape programmability and tunable actuating behaviors are highly desired but still challenging.In this study,we propose an orthogonal composite design to develop such a material.The developed composite elastomer comprises carboxyl group-grafted polystyrene-block-poly(ethylene-co-butylene)-block-polystyrene(SEBS-g-COOH)as the elastic substrate,and a synthesized azobenzene derivative as the functional filler(Azo12).By surface treatment using acidic and base solutions,the carboxyl groups on the surface can reversibly transform into carboxylate groups,which render the composite tunable hygroscopic actuating functionality.On another aspect,the added filler undergoes trans-to-cis isomerization when exposed to UV light irradiation,leading to liquefaction of the crystalline aggregates formed by Azo12 molecules.The liquefied Azo12 molecules can autonomously resotre their trans form and reform the crystalline structure.This reversible change in crystralline structure is utilized to realize the shape memory property,and 5 wt%of Azo12addition is adequate for the composite to exhibit photo-responsive shape memory behavior without compromising much of the elasricity.The regualtion of external geometry by shape memory effect is effective in altering the actuating behavior.The proposed method can be extend to designing different composites with the demonstrated functionalities.
基金Natural Science Foundation of China(51873188,21434006).
文摘Cell migration in three-dimensional environment is extremely important for tissue regeneration and other biological processes.In this work,a model system was developed to study how endothelial cells(ECs)migrate into photo-responsive hydrogels under the presence of pro-inflammatory macrophages.The hydrogel was synthesized from hyaluronic acid grafted with coumarin and methacrylate moieties by both carbon–carbon covalent linking and coumarin dimerization under UV irradiation at 365 nm.The structure of the hydrogel was conveniently modulated by UV irradiation at 254nm to decompose the coumarin dimers,leading to the significant decrease of modulus and increase of swelling ratio and mesh size.Under the presence of M1 macrophages,ECs were induced to migrate into the hydrogels with a different degree.A significant larger net displacement of ECs was found in the softer hydrogel obtained by irradiation with UV at 254nm than in the stiffer original one at day 7.
基金supported by the National Natural Science Foundation of China (Nos. 21425314, 21501184, 20141061)Beijing Municipal Science & Technology Commission (No. Z161100000116037)+1 种基金the Top-Notch Young Talents Program of ChinaYouth Innovation Promotion Association, CAS (No. 2017036)
文摘Photo-responsive polymer materials from zero-dimensional micelles, two-dimensional surfaces to three-dimensional hydrogels have been designed, synthesized and applied for various biological fields including drug delivery and cell manipulation. Many remarkable works have been reported, revealing the advantages of photo-responsive polymers such as noninvasion and spatiotemporal control. In this review, we briefly summarized the remarkable progress of photo-responsive polymers with irreversible or reversible moieties and their further biological applications. The future opportunities and challenges of photo-responsive polymer materials are also proposed.
基金The work was financially supported by the National Natural Science Foundation of China(Grant No.21650110447).
文摘The conformation-dependent activity of azo-benzene combretastatin A4(Azo-CA4)provides a unique approach to reduce the side-effects of chemotherapy,due to the light-triggered conformation transition of its azobenzene moiety.Under hypoxic tumor microenviron-ment,however,the high expression of azoreductase can reduce azobenzene to aniline.It was postulated that the Azo-CA4 might be degraded under hypoxia,resulting in the decrease of its anti-tumor activity.The aim of this study was to verify such hypothesis in HeLa cells in vitro.The quantitative drug concentration analysis shows the ratio-metric formation of degradation end-products,confirming the bioreduction of Azo-CA4.The tubulin staining study indicates that Azo-CA4 loses the potency of switching off microtubule dynamics under hypoxia.Furthermore,the cell cycle analysis shows that the ability of Azo-CA4 to induce mitotic arrest is lost at low oxygen content.Therefore,the cytotoxicity of Azo-CA4 is compromised under hypoxia.In contrast,combretastatin A4 as a positive control maintains the potency to inhibit tubulin polymer-ization and break down the nuclei irrespective of light irradiation and oxygen level.This work highlights the influence of hypoxic tumor microenvironment on the anti-tumor potency of Azo-CA4,which should be considered during the early stage of designing translational Azo-CA4 delivery systems.
基金We acknowledge financial support from the National Natural Science Foundation of China (Nos.21234004,91027023,21221063,and 21004028) and the 111 project (No.B06009).
文摘Glutathione peroxidase (GPx) is a vital antioxidant enzyme involved in the reduction of reactive oxygen species and protects cells from oxidative damage.Consequently enormous efforts have been devoted to developing artificial catalysts with GPx function.Besides the research on enhancing the catalytic activity of GPx mimics,the design and construction of smart GPx models has also inspired great interest.Herein,a novel photo-responsive seleniumcontaining vesicular GPx model was successfully constructed by supramolecular self-assembly of the cationic surfactant PyC10AZoC10Py with benzeneseleninic acid (PhSeO2H) through hydrophobic and electrostatic interactions in aqueous media.This selenium-containing vesicular catalyst showed remarkable GPx-like activity,which is 692times more effective than PhSeO2H for the reduction of cumene hydroperoxide (CUOOH) by 4-nitrobenzenethiol (NBT).Interestingly,when an equimolar amount of α-CD was added,the GPx-like activity of the catalytic vesicle declines remarkably due to the vesicle disaggregation in the presence ofα-CD.Whereas the biomimetic system was irradiated by UV light at 365 nm,the catalytic vesicle was formed again and the GPx-like activity recovered.
基金supported by the National Natural Science Foundation of China (Nos. 22175074, 21822507)。
文摘Stimuli-responsive macrocycles are of importance for synthetic chemistry and smart materials. In this manuscript, we report two novel organoborane cyclophanes, which were successfully synthesized by ruthenium-catalyzed olefin metathesis. They are composed of one/two boron-doped helicene π-skeletons and flexible alkyl chain linkers, thus representing a new kind of non-conjugated organoborane macrocycles. Their cyclic structures and photophysical properties, as well as Lewis acidity were theoretically and experimentally investigated. Notably, two enantiomers in one single crystal are observed for one organoborane cyclophane, owning to the presence of helical π-framework in its cyclic structure. Moreover, their Lewis acid-base adducts may dissociate in the excited state and thus display intriguing photo-responsive fluorescence properties, which can be further modulated by temperature. This study thus provides a novel design strategy for non-conjugated organoborane macrocycles, which may promote the development of stimuli-responsive macrocyclic materials with fascinating properties.
基金the National Natural Science Foundation of China(Nos.21603111,51702173)Guangdong Basic and Applied Basic Research Foundation(No.2020B1515020038)the Pearl River Talent Recruitment Program of Guangdong Province(No.2019QN01L148)。
文摘Direct alcohol fuel cells(DAFCs)have received wide attention as a new type of clean energy device because of their high energy conversion efficiency,portability,non-toxicity and pollution-free.Anode catalysts are the key factors affecting the performance of DAFCs.Recently studies show that using the optical activity of semiconductor materials as the carriers of traditional precious metal electrocatalysts,under the illumination of light sources,can greatly improve the electrocatalytic activity and stability of electrodes.In this review,the research progress of photo-responsive metal/semiconductor hybrids as the electrocatalysts for DAFCs in recent years is summarized,including:(1)Mechanism and advantages of photo-assistant electrochemical alcohol oxidation reaction,(2)me tal/semiconductor electrocatalyst for the different type of fuel cell reactions,(3)different kind of metals in photo-responsive metal/semiconductor hybrid nanostructure,(4)the personal prospects of the photo-responsive metal/semiconductor electrode for future application in DAFCs.
基金financially supported by the Natural Science Foundation of Fujian Province(Nos.2021J02007,2021J01553)Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China(No.2021ZR148)。
文摘The exploration of novel photo/thermal-responsive nonvolatile memorizers will be beneficial for energysaving memories.Herein,new<110>-oriented perovskites using single template melamine,i.e.,[(MLAI-H_(2))(PbX_(4))]_n(X=Br (α-1),Cl (α-2),MLAI=melamine) have been prepared and their structures upon irradiation of visible light have been investigated.They have been fabricated as nonvolatile memory devices with structures of ITO/[(MLAI-H_(2))(PbX_(4))]_n/PMMA/Ag (device-1:X=Br,device-2:X=Cl),which can exhibit unique visible light-triggered binary nonvolatile memory performances.Interestingly,the silent or working status can be monitored by visible chromisms.Furthermore,the light-triggered binary resistive switching mechanisms of these ITO/[(MLAI-H_(2))(PbX_(4))]_n/PMMA/Ag memory devices have been clarified in terms of EPR,fluorescence,and single-crystal structural analysis.The presence of light-activated traps in<110>-oriented[(MLAI-H_(2))(PbX_(4))]_n perovskites are dominated in the appearance of light-triggered resistive switching behaviors,based on which the inverted internal electrical fields can be established.According to the structural analysis,the more distorted PbX_6octahedra,higher corrugated<110>-oriented perovskite sheets,and more condensed organic-inorganic packing in Br-containing perovskite are beneficial for the stabilization of light-activated traps,which lead to the better resistive switching behavior of device-1.This work can pave a new avenue for the establishment of novel energy-saving nonvolatile memorizers used in aerospace or military industries.
基金supported by the Natural Science Foundation of Beijing Municipality,China (No.Z180016)the National Natural Science Foundation of China (No.21971248).
文摘Ultraviolet light(UV)is an essential component of ambient light,but high dose UV would damage genome DNA.While semiconductors and soft materials have been employed to detect the UV,the complex process and the instrumental requirement have limited the application in daily life.In this study,taking advantage of sequence designability,a series of hydrogels with different gel-sol transition rates was constructed under the same UV intensity by introducing competing hybridization to tune the stability of the molecular network.Through estimating the transition time between each system under UV light irradiation,the intensity of UV could be roughly estimated,which provided a convenient method for the visual detection of UV.
基金This work was supported by the National Natural Science Foundation of China(No.21905197)the Starting Grants of Tianjin University and Tianjin Government,China.
文摘The research of photo-responsive materials,with changed absorption and emission under light stimulus,has drawn more and more attention due to their wide applications.However,most of them suffered from the notorious aggregation-caused quenching(ACQ)effect,which often led to the unconspicuous luminescent change in photo-responsive process.To solve this problem,the strategy of combining aggregation-induced emission(AIE)and photochromic properties was utilized,which largely enriched the phenomenon and application of photo-responsive materials.This short review summarized the recent progress of photo-responsive AIE materials with changed UV absorbance or PL phenomenon under UV-irradiation,including the types of molecular structures,internal mechanisms and the practical applications.Also,some outlooks were given on the further exploration of this field at the end of this paper.
基金supported by the National Natural Science Foundation of China(Nos.51703112,51673106)Natural Science Foundation of Shandong Province(Nos.ZR2017BEM040,ZR2016BQ28)+1 种基金Open Fund of the State Key Laboratory of Luminescent Materials and Devices(No.2017-skllmd-10,South China University of Technology)China Postdoctoral Science Foundation(No.2017M622152).
文摘Photo-responsive mechanical actuator is a class of stimuli-responsive materials transferring light to mechanical energy through macroscopic transformation.To fabricate photo-responsive mechanical actuator,soft polymeric materials crosslinked with functional bridging structures are desired.Supramolecular interaction is a relatively common way to fabricate crosslinked materials due to its excellent self-assembly performance.And azobenzene and derivatives are ideal candidates of photo-responsive materials because of the unique photo-induced trans-cis isomerization.Here,a new kind of crosslinked materials based on supramolecular interaction between 4,4'-dihydroxyazobenzene and chitosan is reported.Under 355 nm irradiation,the macroscopic bending of polymeric materials occurs rapidly due to the photo-isomerization of 4,4-dihydroxyazobenzene.Meanwhile,the photo-responsive mechanical actuator can also lift weight which is up to 200 times that of the actuator itself,and convert energy from light to mechanical work efficiently.This report suggests a new kind of photo-responsive actuator based on supramolecular interaction and may be helpful to contribute a theoretical basis to the design and synthesis of photo-responsive mechanical actuator suitable for large-scale manufacturing industrialization in future.
基金This work was financially supported by the National Natural Science Foundation of China(Nos.22075044 and 21574021)the Natural Science Foundation of Fujian Provinee(No.2018J01670)+1 种基金Educational Commission of Fujian Province(No.JAT170129)the Scientific Research Starting Foundation for researchers with PhD of Fujian Normal University.
文摘Solid-stated smart polymers responsive to external stimuli have attracted much attention for potential application in the field of photoelectron devices,logic gates,sensor,data storage and security.However,it is a bigger challenge for polymers than that for small molecules in solid state to acquire stimuli-responsive properties,because polymers with high molecular weight are not as easy to change the packing structure as small molecules under external stimulation.Here,a D-A type alternating copolymer PTMF-o containing 3,4-bisthienylmaleimide(A unit)and fluorene(D unit)is designed and synthesized.Upon irradiation of sunlight,PTMF-o film exhibits a photo-response with the color altering from purple to colorless.It is attributed to the structure of copolymer transformed from ring-opening form(PTMF-o)to ring-closure form(PTMF-c),resulting from the oxidative photocyclization of 3,4-bisthienylmaleimide unit.Consequently,the ability of charge transfer(CT)from fluorene to 3,4-bisthienylmaleimide unit in PTMF-o can be easily weakened by light stimuli.PTMF-o film displays a WORM-type resistive storage performance for the strong CT.Interestingly,after exposure,the electrical memory behavior in situ transfers into FLASH type,due to weak CT in PTMF-c.PTMF-o film can also be employed as smart material to construct NAND and NOR logic gates by using light as input condition.The work provides a simple way to modify the electronic properties of polymers and realize stimuli-response in solid states.
基金Nanomission,Department of Science and Technology,Govt. of India for financial support as sponsored project:Theme Unit of Excellence in Nanodevice Technology
文摘We investigated the feasibility of obtaining large photoresponse in metal-semiconductor-metal(MSM) type single nanowire device where one contact can be blocking type. We showed that suitable modification of the blocking contact by deposition of a capping metal using focused electron beam(FEB) can lead to considerable enhancement of the photoresponse. The work was done in a single Cu:TCNQ nanowire device fabricated by direct growth of nanowires(NW) from pre-patterned Cu electrode which makes the contact ohmic with the other contact made from Au. Analysis of the data shows that the large photoresponse of the devices arises predominantly due to reduction of the barriers at the Au/NW blocking contact on illumination. This is caused by the diffusion of the photo generated carriers from the nanowires to the contact region. When the barrier height is further reduced by treating the contact with FEB deposited Pt, this results in a large enhancement in the device photoresponse.
基金supported by National Natural Science Foundation of China(Grant No.22278069,21978046)Textile Vision Basic Research Program(J202005).
文摘The smart emulsification and demulsification system with the light response is a useful tool in various industries,including green chemistry,catalytic reaction,pharmaceuticals,and environmental remediation.Herein,an ionic liquid crystal compound with a light triggered switch based on the azobenzene group[(4-{3-methyl-1-[3-(8-octyloxyoctyl)oxy-4-oxobutanoyl]imidazo-lium-1-yl}octyl)oxy]-N-(4-methylphenyl)benzene-1,2-diazene bromide(MOIAzo),was designed and synthesized,which could cause reversible transition between emulsification and demulsification through the light trigger.The ionic liquid has an efficient photoinduced liquefaction process,which dramatically lowers the melting point of ionic liquids from 79 to 9.2 oC.This significantly broadens the liquid state temperature of the ionic liquid crystal.The ionic liquid crystal MOIAzo exhibits both photoinduced and thermally induced nematic liquid crystal properties.The smart emulsion system was effectively employed in an eco-friendly water-saving dyeing process of cationic dyes for cationic dyeable polyester(CDP)fabrics,which used only half the amount of water compared with the conventional water bath dyeing method.After dyeing,the oil and water phases can be efficiently separated through the light irradiation,and the oil phase can be reused for the subsequent dyeing process.This novel smart emulsion dyeing method greatly reduces the water consumption and wastewater discharge.MOIAzo as a lighttriggered ionic liquid molecule opens up new dimensions in green chemistry.
文摘A three-transistor active pixel sensor and its double sampling readout circuit implemented by a switch capacitor amplifier are designed. The circuit is embedded in a 64 × 64 pixel array CMOS image sensor and success-fully taped out with a Chartered 0.35μm process. The pixel pitch is 8μm × 8μm with a fill factor of 57%, the photo-sensitivity is 0.8V/（lux · s） ,and the dynamic range is 50dB. Theoretical analysis and test results indicate that as the process is scaled down, a smaller pixel pitch reduces the sensitivity. A deep junction n-well/p-substrate photodiode with a reasonable fill factor and high sensitivity are more appropriate for submicron processes.
基金Supported by Key Technology Integration and Demonstration of Xinjiang Characteristic Fruit Trees’ High Efficiency and Safe Production,Science and Technical Plan Project of Xinjiang Uygur Autonomous Region(201130102-1)Earmarked Fund for China Agriculture Research System(CARS-30)Financial Aid from Key Fruit Trees Subject of Xinjiang Uygur Autonomous Region~~
文摘[Objective] This study compared the leaf photosynthetic characteristics of Turpan grape cultivated in greenhouses and open field to provide a scientific basis for the high-quality and high-yield cultivation of grape. [Method] Two precocious grape varieties as experimental materials were cultivated in greenhouses and open field, and their net photosynthetic rates （Pn）, photo-response curves and CO2 response curves were determined using Li-400XT portable photosynthesis system. [Result] The leaf Pn of the two varieties cultivated in open field was higher than that in greenhouse. The Pn of Hongqitezao cultivated in open field was the highest, up to 19.79 μmol/（m^2·s）; in the photo-response curves, Hongqitezao cultivated in greenhouse had the largest Pnmax and apparent quantum yield （AQY）, while the Flame Seedless in greenhouse had the smallest light compensation point （LCP）. The light saturation point （LSP） value of greenhouse cultivation was higher than that of open field cultivation. In the CO2 response test, the dark respiration rate （Rd） and Pnmax of greenhouse cultivation were higher than those of open field cultivation, and the carboxylation efficiency （CE） of greenhouse cultivation was lower than that of open field cultivation; the CO2 compensation point （CCP） and CO2 saturation point （CSP） of greenhouse cultivation were lower than those of open field cultivation. [Conclusion] The utilization of elevated light in greenhouse cultivation was more efficient than in open field cultivation; however, the utilization of elevated CO2 in greenhouse cultivation was weaker than tin open field cultivation.
基金Financial support from the National Natural Science Foundation of China (Nos.21631003,21771192,and 21871024)the Fundamental Research Funds for the Central Universities (No.FRF-BR-18–009B)。
文摘It is an urgent task to develop highly efficient non-noble metal electrocatalysts in the direction of ORR,but still a huge and long-term challenge.Herein,an efficient one-step pyrolysis of Sichuan pepper powder,2,2-bipyridine,FeCl3,Na SCN,and ZnCl2 at 900℃ provides the FeS/ZnS@N,S-C-900 hybrid catalyst.Transmission electron microscopy(TEM)images and Mott-Schottky curves clearly reveal the in-situ constructed abundant FeS/ZnS-based p-n junctions dispersed on the biomass-derived porous carbon surface of FeS/ZnS@N,S-C-900.The as-prepared FeS/ZnS@N,S-C-900 hybrid exhibits superior ORR performance in comparison with Pt/C in 0.1 M KOH with high onset(Eonset)and half-wave potentials(E1/2)of 1.00 and 0.880 V vs.RHE,large limiting current density(JL)of 5.60 mA cm-2,and robust durability and methanol tolerance.Impressively,upon the light irradiation,FeS/ZnS@N,S-C-900 produces a photocurrent as high as ca.0.3μA cm-2,resulting in further improvement over Eonset,E1/2,and JLof FeS/ZnS@N,S-C-900 to1.10 V vs.RHE,0.885 V vs.RHE,and 6.02 mA cm-2.Experiment in combination with theoretical calculations demonstrate the significant effect of FeS/ZnS heterojunction on the enhanced ORR catalytic activity of FeS/ZnS@N,S-C-900.This work is useful for the development of advanced heterojunction-based ORR catalysts for various energy conversion devices.
