The fluorine-substituted benzoate ester rod-shaped liquid crystals containing an azobenzene side chain linked with terminal double bonds were synthesized and characterized.The mesophase and photoswitching properties w...The fluorine-substituted benzoate ester rod-shaped liquid crystals containing an azobenzene side chain linked with terminal double bonds were synthesized and characterized.The mesophase and photoswitching properties were determined by polarizing optical microscopy（POM）,differential scanning calorimetry（DSC） and UV-visible spectrometry.The rod-shaped compound 4a having an odd number of carbon atoms in the alkyl chains exhibits nematic phase and SmA type phase whereas compound 4b having an even number of carbon atoms showed only nematic phase.Both fluorinecontaining compounds 4c and 4d showed only SmA type phases.The photoswitching properties of these compounds showed a rate of trans to cis isomerization ranging 19-20 s,whereas reverse process took around 230 min in solution.These materials may be ideal in the field of optically rewritable applications where both on and off rates should be crucial.展开更多
Photoresponsive supramolecular systems have merited extensive attention for their applications in materials science and life science.Here,we synthesized a water-soluble stiff-stilbene molecular photoswitch,exhibiting ...Photoresponsive supramolecular systems have merited extensive attention for their applications in materials science and life science.Here,we synthesized a water-soluble stiff-stilbene molecular photoswitch,exhibiting outstanding photoisomerization reaction between its(E)-and(Z)-configurations upon irradiation at distinct light.The photoswitch can assemble with cucurbit[7]uril(CB[7])to form a superior fluorescent supramolecular complex(compared to the only vip)with excellent water solubility,which manifested dramatic photoluminescence enhancement caused by restriction of intramolecular rotation and remained good photochromic characteristics.Furthermore,introduction of CB[7]influence photoreaction quantum yield(Φ)of the stiff-stilbene,leading to reduction ofΦ_(E→Z) and increase ofΦ_(Z→E) of the stiff-stilbene.Importantly,the photoadjustable supramolecular assembly can act as a fluorescence switch,and the phototunable vip further selectively modulate G-quadruplex structure of Tel22 upon light irradiation or with addition of CB[7].The study provides a new simple way for accurately regulating photochromic properties of molecular switches and developing smart materials with potential applications in controlled modulation of G-quadruplex,targeted biological imaging and so on.展开更多
Lanthanide-doped photon-avalanche(PA)upconversion(UC)nanoparticles(NPs),characterized by highly nonlinear optical response,have recently attracted tremendous interest for applications in many frontier areas such as su...Lanthanide-doped photon-avalanche(PA)upconversion(UC)nanoparticles(NPs),characterized by highly nonlinear optical response,have recently attracted tremendous interest for applications in many frontier areas such as super-resolution imaging[1],dynamic photoswitching[2],ultrasensitive optical sensing[3],and high-density optical memory and computing[4].Specifically,the large nonlinearities(N)of PA have fueled the development of low-cost,single-beam super-resolution imaging techniques,offering a√N-fold improvement in spatial resolution[5].Although PA NPs with N plateauing 60s have been developed through energy transfer engineering based on core/shell architecture[6],further enhancement remains challenging.展开更多
Photoswitchable fluorescent polymeric nanoparticles were widely concerned because of their excellent features including the flexible design,easy preparation and functionalization,and thus exhibited great application p...Photoswitchable fluorescent polymeric nanoparticles were widely concerned because of their excellent features including the flexible design,easy preparation and functionalization,and thus exhibited great application potential in information encryption,anti-counterfeiting,but remained challenging in improving the security.Herein,we described a self-erased time-resolved information encryption via using photoswitchable dual-color fluorescent polymeric nanoparticles(PDFPNs)containing two fluorescence dyes(blue and red)and photochromic spiroxazine derivatives.In view of the different thermo-induced isomerization rates of photochromic spiroxazine derivatives in different flexible substrates,the decoloration rate of PDFPNs can be programmatically tuned by regulating ratio between rigid polymer and flexible polymer.Therefore,after ultraviolet light(UV)irradiation,correct information could only be recognized in preestablished time during the self-erased process.Our results indicated that PDFPNs exhibited fast photo-responsibility(2 min),high fluorescence contrast,well-pleasing photo-reversibility(>20 times),and programmable thermo-responsiveness(24 s-6 h).We thus demonstrated their application in the selferased time-resolved information encryption and anti-counterfeiting with high security.展开更多
Photochromic materials with multicolor upconversion reversible modulations are attractive in optical switching devices.Herein,the fabricated YNbO_(4):Er^(3+)/Tm^(3+)/Yb^(3+) materials exhibit excellent photochromism a...Photochromic materials with multicolor upconversion reversible modulations are attractive in optical switching devices.Herein,the fabricated YNbO_(4):Er^(3+)/Tm^(3+)/Yb^(3+) materials exhibit excellent photochromism and multicolor upconversion properties from green,red to near infrared(NIR) emissions with increasing Yb concentrations.Reversible multiband upconversion modulations are achieved by alternating light(365 and 405 nm) or thermal stimuli.After 365 nm irradiation,the luminescence color changes from yellow to red,the luminescent photoswitching contrast reaches up to 86.21%(green),82.12%(red) and 77.38%(NIR) in the Y_(0.83)Er_(0.01)Tm_(0.01)NbO_(4):0.15 Yb sample.Besides,the upconversion emission intensity before and after photochromic reaction shows remarkable change in a wide temperature range of 298-718 K.These results indicate that the Er^(3+)/Tm^(3+)/Yb^(3+) tri-doped YNbO_(4) materials can be a good candidate in optical switching and data storage applications.展开更多
For the main purpose of manipulating the functions of molecules, researchers have made great achievements on photoresponsive molecules using light as a trigger. Light has become a promising scientific tool due to it b...For the main purpose of manipulating the functions of molecules, researchers have made great achievements on photoresponsive molecules using light as a trigger. Light has become a promising scientific tool due to it being a clean and noninvasive external stimulant. By attachment of photoresponsive moieties to molecules, the biological activities of molecules can be attenuated by light activation. With wide applications of laser in life sciences, it will be possible to achieve high spatiotemporal resolution. In this review, we focus on photoresponsive nucleic acids for photomodulating gene expression with light activation. With incorporation of photoswitchable or photocleavable moieties, biological behaviors of nucleic acids are photoregulated reversibly or irreversibly. Recent development and applications of photoresponsive nucleic acid in vitro and in vivo have shown a very promising future for manipulation of specific functional genes or disease genes. We expect that photoresponsive nucleic acids will be powerful scientific tools for studying biological events as well as gene therapy agents for genetic diseases.展开更多
Photo-responsive azobenzene （ABZ） derivatives with different end groups （R） as photoswitchable molecules were employed to construct self-assembled monolayers （SAMs） on silicon substrate by using 3-glycidoxypropy...Photo-responsive azobenzene （ABZ） derivatives with different end groups （R） as photoswitchable molecules were employed to construct self-assembled monolayers （SAMs） on silicon substrate by using 3-glycidoxypropyltrimethoxysilane （GPTS） as the bridging molecules. The assembly process was optimized by changing various parameters, including the type and concentration of ABZ derivatives, reaction time, etc. The obtained SAMs were fully characterized and evaluated using UV spectroscopy, atomic force microscope （AFM）, elllipsometer, static contact angle and X-ray photoelectron spectroscopy （XPS）. It is found that the end group property of azobenzene derivatives is critical to the obtained SAMs＇ photoresponsive properties. Compared with hydrophobic compounds （4-（4＇-aminophenylazo） benzoic acid, ABZ-CF3）, the hydrophilic compounds （4-（4＇-aminophenylazo） benzoic acid, ABZ-COOH） show excellent reversible photoswitching performance with a large contact angle change of 35° under oDtimized process, and the SAMs are removable bv thermal treatment at 240 ℃ in air for onlv 5 min.展开更多
The photoisomerization abilities of secondary thioxopeptide bond(CS-NH) and thioxo prolyl bond(CS-N) incorporated into the C-terminal pentapeptide of insect kinin were compared.H-Phe-Phe-Ψ[CS-NH]-D-Ala-Trp-Gly-NH_2 a...The photoisomerization abilities of secondary thioxopeptide bond(CS-NH) and thioxo prolyl bond(CS-N) incorporated into the C-terminal pentapeptide of insect kinin were compared.H-Phe-Phe-Ψ[CS-NH]-D-Ala-Trp-Gly-NH_2 and H-Phe-Tyr-Ψ[CS-N]- Pro-Trp-Gly-NH_2 were studied by UV-vis absorption.The isomerization energy barriers of the two segments,Ac-Phe-Ψ[CS-NH]- D-Ala-NH_2 and Ac-Tyr-Ψ[CS-N]-Pro-NH_2 picked from the two peptides,were calculated using ab initio method.The cis isomer of CS-N is more stable than th...展开更多
The preparation and performance characterization of〈50 nm spirobenzopyran-based photochromic nanocomposites with photoswitchable fluorescence are presented.The nanocomposites were fabricated by means of a modifed min...The preparation and performance characterization of〈50 nm spirobenzopyran-based photochromic nanocomposites with photoswitchable fluorescence are presented.The nanocomposites were fabricated by means of a modifed miniemulsion polymerization process,in which the hydrophobic spirobenzopyran was covalently attached to the polymer chains and the matched fluorescent dyes were noncovalently embedded in the nanoscale cross-linked polymeric matrix,respectively.The obtained nanocomposites with a high relative fluorescence quantum yield（Q）exhibited superior fluorescent photoswitchable performance due to the effective photo-induced intermolecular energy transfer.The stability of photomerocyanine was also improved.展开更多
Tetraphenylethene(TPE),a star building block with promising aggregationinduced emission,has received much interest.Given that its intramolecular Woodward-Hoffmann cyclic intermediate instantaneously converts back to t...Tetraphenylethene(TPE),a star building block with promising aggregationinduced emission,has received much interest.Given that its intramolecular Woodward-Hoffmann cyclic intermediate instantaneously converts back to the original state within several picoseconds,the essentially photochromic characteristic of TPE is little investigated.Achieving a visible photocyclization of TPE is still an unsolved issue and considered as the bottleneck in the further advancement of applications.We report a strategy of attaching carbonate ester onto the TPE skeleton(TPE-4C)to enhance TPE photocyclization stability.As demonstrated,the incorporated cholesteryloxycarbonyloxy substituents in TPE-4C can increase the energy barrier for cycloreversion,thereby exhibiting extremely thermal stability of photocyclic intermediate upon UV irradiation,prolonging its lifetime from 63 picoseconds to 46 s by 7.2×10^(11)-fold.The photoinduced cyclization of TPE-4C could be monitored with naked eyes,and the photocyclization/cycloreversion is achieved by turning on/off UV light along with a relative fatigue resistance.Encapsulation of TPE-4C into the liquid crystal can induce a striking phase transformation(achiral↔chiral),which can be applicable to encode optical information.Employing carbonate ester into the TPE unit plays a vital role in enhancing the unprecedented TPE photocyclization stability,providing a toolbox to allow TPE-based photocyclization to be visually monitored.展开更多
1.Introduction The introduction of photoswitches into the bioactive substances is the fundamental idea behind photopharmacology.Upon light irradiation,the drug activity can be spatiotemporally controlled by the photon...1.Introduction The introduction of photoswitches into the bioactive substances is the fundamental idea behind photopharmacology.Upon light irradiation,the drug activity can be spatiotemporally controlled by the photon-induced variety of photoswitch's structures or characteristics[1].However,some challenges are still faced in photopharmacology including phototoxicity and limited tissue penetration depth(about a few millimeters).展开更多
An interest in the fluorescent protein asFP595 is due to unexplained puzzles in its photophysical behavior. We report the results of calculations of structures, absorption, and emission bands in asFP595 by considering...An interest in the fluorescent protein asFP595 is due to unexplained puzzles in its photophysical behavior. We report the results of calculations of structures, absorption, and emission bands in asFP595 by considering model molecular clusters in the coordinate-locking scheme. Both trans and cis conformations of the anionic chromophore are considered. Equilibrium geometry coordinates on the ground potential energy surface were optimized in the density functional theory approaches by considering both large- and reduced-size clusters. The cluster size was reduced to locate positions of the minimum energy points on the excited-state potential surface by using the configuration interaction singles approach. Vertical excitation energies and oscillator strengths were computed by using the ZINDO method. We show that consideration of large clusters mimicking the protein-containing pocket is an essential issue to calculate positions of absorption and emission bands with the accuracy compatible to experiments.展开更多
Photoswitchable catalysis provides a non-invasive strategy for dynamically controlling light-driven chemical energy conversion processes.The defining advantage of photoswitchable catalytic systems lies in their unique...Photoswitchable catalysis provides a non-invasive strategy for dynamically controlling light-driven chemical energy conversion processes.The defining advantage of photoswitchable catalytic systems lies in their unique dual capacity:i)spatiotemporal precision in resolving reactive species generation through optical addressing;and ii)adaptive multifunctionality enabling on-demand switching between distinct active phases,thereby suppressing competing pathways and eliminating undesired side reactions.展开更多
Recent advancements in single-molecule biophysics have been driven by breakthroughs in advanced fluorescence microscopy techniques and the development of nextgeneration organic fluorophores.These cutting-edge fluoroph...Recent advancements in single-molecule biophysics have been driven by breakthroughs in advanced fluorescence microscopy techniques and the development of nextgeneration organic fluorophores.These cutting-edge fluorophores,coupled through tailored biolabeling strategies,offer single-molecule brightness,photostability,and phototunability(i.e.,photoswitchable,photoactivatable),contributing to enhancing spatial and temporal imaging resolution for studying biomolecular interactions and dynamics at single-event precision.This review examines the progress made over the past decade in the development of next-generation fluorophores,along with their site-specific labeling methods for proteins,nucleic acids,and biomolecular complexes.It also explores their applications in single-molecule fluorescencebased dynamic structural biology and super-resolution microscopy imaging.Furthermore,it examines ongoing efforts to address challenges associated with fluorophore photostability,photobleaching,and the integration of advanced photophysical and photochemical functionalities.The integration of state-of-the-art fluorophores with advanced labeling strategies aim to deliver complementary correlative data,holding promise for revolutionizing single-molecule biophysics by pushing the boundaries of temporal and spatial imaging resolution to unprecedented limits.展开更多
The visible light-driven photoswitches are attracting widespread attention,but it is challenging to leverage their phototriggered structural changes to regulate dynamic bonds,assemblies,and materials.Herein,we incorpo...The visible light-driven photoswitches are attracting widespread attention,but it is challenging to leverage their phototriggered structural changes to regulate dynamic bonds,assemblies,and materials.Herein,we incorporated reversible covalent sites of aldehyde ring-chain tautomers into all-visible-light azobenzenes toward a versatile platform for light-controlled formation/exchange of dynamic C—N bonds from secondary amines.The movement of ring-chain equilibrium was attained via manipulating intramolecular multiple hydrogen bonding from E/Z configurational isomers.Such structural regulation further enabled photocontrolled kinetics for the formation and exchange reactions of cyclic hemiaminal ethers from secondary amines exhibiting kinetic rate reversal from E/Z isomers.The varied capability of E/Z configurational isomers in engaging in multiple hydrogen bonds of azo attached carboxylate with ammonium salt accounts for the difference.Moreover,the photoswitching performance of azobenzenes in different solutions was readily regulated by dynamic covalent reactions with amines.The dynamic reactivity control with visible light and associated mechanistic foundation add into the collection of photoswitchable dynamic covalent chemistry and would lay the foundation for subsequent biological and material applications.展开更多
Molecular photoswitches hold an important position in chemical research,and it is of significance to develop novel structures and mechanisms.Herein we report a new type of E/Z photoswitches in tellurazole/tellurazoliu...Molecular photoswitches hold an important position in chemical research,and it is of significance to develop novel structures and mechanisms.Herein we report a new type of E/Z photoswitches in tellurazole/tellurazolium-based olefin scaffolds,wherein intramolecular through-space n→π^(*)orbital interaction plays a stabilizing role in the Z isomer approaching quantitative conversion.The manipulation of diverse noncovalent interactions,including intermolecular chalcogen bonding,further provided versatile handles for regulating molecular recognition and multiaddressable switching.Despite bidirectional E/Z photoisomerization with neutral tellurazole derivatives,protonation-induced cationic tellurazoliums allowed significant enhancement in the efficiency of Z→E switching(E up to 73%)while maintaining high percentage E→Z switching(Z up to 95%),as chalcogen bonding with counteranions contributes to the stabilization of electron-accepting tellurazoliums affording a larger wavelength difference between E/Z isomers.Furthermore,the n→π^(*)orbital interaction enables the preference of Z isomer in the ground state for N-methyl tellurazoliums.Bidirectional E/Z photoswitching with high conversion(Z up to 99%,E up to 81%)was attained,and E→Z isomerization can also be invoked by nucleophilic catalysis,making N-methyl tellurazoliums as T-type photoswitches.The results showcase the power of noncovalent interactions for controlling molecular photoswitches and should set the scene for vip recognition,dynamic assemblies,and responsive materials.展开更多
The wide application of photoswitches requires control over their isomerization dynamics.Utilizing noncovalent interactions is a promising strategy as it offers active regulation in-situ.However,this control strategy ...The wide application of photoswitches requires control over their isomerization dynamics.Utilizing noncovalent interactions is a promising strategy as it offers active regulation in-situ.However,this control strategy has not yet been explored in-depth to reach its full potential.In this work,we demonstrate that by directing noncovalent interactions to the central rotating bond of indigo-based photoswitches,their thermal relaxation dynamics were altered in two opposite directions(either slowed down or sped up)allowing for modulating the relaxation half-lives across four orders of magnitude.More importantly,our work established two distinct and orthogonal working mechanisms of noncovalent control over isomerization:(1)Thermodynamic stabilization of photoisomers;and(2)Facilitating an alternative reaction pathway through Brønsted/Lewis acid catalysis.This two-directional modulation(resembling agonists and inverse agonists in biological systems)via two orthogonal working mechanisms will enable more delicate manipulation of photoswitches for advanced applications.展开更多
Modulating photoluminescent(PL)materials is crucial for applications such as super-resolution microscopy.The combination of PL materials and photoswitches can achieve this aim by utilizing isomerization of the photosw...Modulating photoluminescent(PL)materials is crucial for applications such as super-resolution microscopy.The combination of PL materials and photoswitches can achieve this aim by utilizing isomerization of the photoswitches.Here we report an optically PL switchable system by mixing carbon quantum dots(CQDs)and diarylethene(DAE)molecular photoswitches.The PL on/off states of CQDs,switched with alternating visible and UV light,achieve a PL on/off ratio of500 and stable reversibility over 20 cycles.The mechanism of our design is revealed by PL lifetime measurements,temperature-dependent PL spectroscopy,and density functional theory(DFT)calculations,confirming that efficient static quenching and the inner filter effect between CQDs and closed DAEs are the keys to achieving such outstanding performance.展开更多
Photochromic diarylethenes have been widely used in many fields. However, their cyclization process must be induced by UV light. In this article, a simple strategy is developed by extending π-conjugation with electro...Photochromic diarylethenes have been widely used in many fields. However, their cyclization process must be induced by UV light. In this article, a simple strategy is developed by extending π-conjugation with electron donating groups. The modified dirylethene derivative can photocyclolize under 405-nm light with a good photochromic efficiency. Meanwhile, its absorption and moderate fluorescence can be switched effectively in both directions by visible lights(405 and 520 nm, respectively) in different solutions and in living cells. We believe that this simple method will become a versatile strategy for developing various dirylethylenes with visible-light photochromism.展开更多
Recently reported plasmon-induced transparency(PIT)in metamaterials endows the optical structures in classical systems with quantum optical effects.In particular,the nonreconfigurable nature in metamaterials makes mul...Recently reported plasmon-induced transparency(PIT)in metamaterials endows the optical structures in classical systems with quantum optical effects.In particular,the nonreconfigurable nature in metamaterials makes multifunctional applications of PIT effects in terahertz communications and optical networks remain a great challenge.Here,we present an ultrafast process-selectable modulation of the PIT effect.By incorporating silicon islands into diatomic metamaterials,the PIT effect is modulated reversely,depending on the vertical and horizontal configurations,with giant modulation depths as high as 129%and 109%.Accompanied by the enormous switching of the transparent window,remarkable slow light effect occurs.展开更多
基金supported by UMP Research(No.RDU 100338)RAGS(No.RDU131408)
文摘The fluorine-substituted benzoate ester rod-shaped liquid crystals containing an azobenzene side chain linked with terminal double bonds were synthesized and characterized.The mesophase and photoswitching properties were determined by polarizing optical microscopy（POM）,differential scanning calorimetry（DSC） and UV-visible spectrometry.The rod-shaped compound 4a having an odd number of carbon atoms in the alkyl chains exhibits nematic phase and SmA type phase whereas compound 4b having an even number of carbon atoms showed only nematic phase.Both fluorinecontaining compounds 4c and 4d showed only SmA type phases.The photoswitching properties of these compounds showed a rate of trans to cis isomerization ranging 19-20 s,whereas reverse process took around 230 min in solution.These materials may be ideal in the field of optically rewritable applications where both on and off rates should be crucial.
基金We thank Top-Notch Talents Program of Henan Agricultural University(No.30501049)Project supported by the Science and Technology Department of Henan Province(No.212102310332)the Merit Funding for the Oversea Staff of Henan Province for financial support.
文摘Photoresponsive supramolecular systems have merited extensive attention for their applications in materials science and life science.Here,we synthesized a water-soluble stiff-stilbene molecular photoswitch,exhibiting outstanding photoisomerization reaction between its(E)-and(Z)-configurations upon irradiation at distinct light.The photoswitch can assemble with cucurbit[7]uril(CB[7])to form a superior fluorescent supramolecular complex(compared to the only vip)with excellent water solubility,which manifested dramatic photoluminescence enhancement caused by restriction of intramolecular rotation and remained good photochromic characteristics.Furthermore,introduction of CB[7]influence photoreaction quantum yield(Φ)of the stiff-stilbene,leading to reduction ofΦ_(E→Z) and increase ofΦ_(Z→E) of the stiff-stilbene.Importantly,the photoadjustable supramolecular assembly can act as a fluorescence switch,and the phototunable vip further selectively modulate G-quadruplex structure of Tel22 upon light irradiation or with addition of CB[7].The study provides a new simple way for accurately regulating photochromic properties of molecular switches and developing smart materials with potential applications in controlled modulation of G-quadruplex,targeted biological imaging and so on.
基金the National Natural Science Foundation of China(Nos.12474418,U22A20398,22135008)the Natural Science Foundation of Fujian Province(No.2024J010038).
文摘Lanthanide-doped photon-avalanche(PA)upconversion(UC)nanoparticles(NPs),characterized by highly nonlinear optical response,have recently attracted tremendous interest for applications in many frontier areas such as super-resolution imaging[1],dynamic photoswitching[2],ultrasensitive optical sensing[3],and high-density optical memory and computing[4].Specifically,the large nonlinearities(N)of PA have fueled the development of low-cost,single-beam super-resolution imaging techniques,offering a√N-fold improvement in spatial resolution[5].Although PA NPs with N plateauing 60s have been developed through energy transfer engineering based on core/shell architecture[6],further enhancement remains challenging.
基金financially supported by the National Key R&D Program of China(Nos.2023YFB3812400,2023YFB3812403)National Natural Foundation of China(Nos.52273206,52350233)+1 种基金Hunan Provincial Natural Science Foundation(No.2021JJ10029)Huxiang High-level Talent Gathering Project(No.2022RC4039).
文摘Photoswitchable fluorescent polymeric nanoparticles were widely concerned because of their excellent features including the flexible design,easy preparation and functionalization,and thus exhibited great application potential in information encryption,anti-counterfeiting,but remained challenging in improving the security.Herein,we described a self-erased time-resolved information encryption via using photoswitchable dual-color fluorescent polymeric nanoparticles(PDFPNs)containing two fluorescence dyes(blue and red)and photochromic spiroxazine derivatives.In view of the different thermo-induced isomerization rates of photochromic spiroxazine derivatives in different flexible substrates,the decoloration rate of PDFPNs can be programmatically tuned by regulating ratio between rigid polymer and flexible polymer.Therefore,after ultraviolet light(UV)irradiation,correct information could only be recognized in preestablished time during the self-erased process.Our results indicated that PDFPNs exhibited fast photo-responsibility(2 min),high fluorescence contrast,well-pleasing photo-reversibility(>20 times),and programmable thermo-responsiveness(24 s-6 h).We thus demonstrated their application in the selferased time-resolved information encryption and anti-counterfeiting with high security.
基金Project supported by the National Natural Science Foundation of China(52062042,51802164)the Natural Science Foundation of Inner Mongolia(2020MS05044)。
文摘Photochromic materials with multicolor upconversion reversible modulations are attractive in optical switching devices.Herein,the fabricated YNbO_(4):Er^(3+)/Tm^(3+)/Yb^(3+) materials exhibit excellent photochromism and multicolor upconversion properties from green,red to near infrared(NIR) emissions with increasing Yb concentrations.Reversible multiband upconversion modulations are achieved by alternating light(365 and 405 nm) or thermal stimuli.After 365 nm irradiation,the luminescence color changes from yellow to red,the luminescent photoswitching contrast reaches up to 86.21%(green),82.12%(red) and 77.38%(NIR) in the Y_(0.83)Er_(0.01)Tm_(0.01)NbO_(4):0.15 Yb sample.Besides,the upconversion emission intensity before and after photochromic reaction shows remarkable change in a wide temperature range of 298-718 K.These results indicate that the Er^(3+)/Tm^(3+)/Yb^(3+) tri-doped YNbO_(4) materials can be a good candidate in optical switching and data storage applications.
基金State Key Laboratory of Natural and Biomimetic Drugs and Peking University(bmu2009137-121)
文摘For the main purpose of manipulating the functions of molecules, researchers have made great achievements on photoresponsive molecules using light as a trigger. Light has become a promising scientific tool due to it being a clean and noninvasive external stimulant. By attachment of photoresponsive moieties to molecules, the biological activities of molecules can be attenuated by light activation. With wide applications of laser in life sciences, it will be possible to achieve high spatiotemporal resolution. In this review, we focus on photoresponsive nucleic acids for photomodulating gene expression with light activation. With incorporation of photoswitchable or photocleavable moieties, biological behaviors of nucleic acids are photoregulated reversibly or irreversibly. Recent development and applications of photoresponsive nucleic acid in vitro and in vivo have shown a very promising future for manipulation of specific functional genes or disease genes. We expect that photoresponsive nucleic acids will be powerful scientific tools for studying biological events as well as gene therapy agents for genetic diseases.
基金financially supported by The Dow Chemical Company
文摘Photo-responsive azobenzene （ABZ） derivatives with different end groups （R） as photoswitchable molecules were employed to construct self-assembled monolayers （SAMs） on silicon substrate by using 3-glycidoxypropyltrimethoxysilane （GPTS） as the bridging molecules. The assembly process was optimized by changing various parameters, including the type and concentration of ABZ derivatives, reaction time, etc. The obtained SAMs were fully characterized and evaluated using UV spectroscopy, atomic force microscope （AFM）, elllipsometer, static contact angle and X-ray photoelectron spectroscopy （XPS）. It is found that the end group property of azobenzene derivatives is critical to the obtained SAMs＇ photoresponsive properties. Compared with hydrophobic compounds （4-（4＇-aminophenylazo） benzoic acid, ABZ-CF3）, the hydrophilic compounds （4-（4＇-aminophenylazo） benzoic acid, ABZ-COOH） show excellent reversible photoswitching performance with a large contact angle change of 35° under oDtimized process, and the SAMs are removable bv thermal treatment at 240 ℃ in air for onlv 5 min.
基金supported by the grant from National Natural Science Foundation of China(No.30870526)
文摘The photoisomerization abilities of secondary thioxopeptide bond(CS-NH) and thioxo prolyl bond(CS-N) incorporated into the C-terminal pentapeptide of insect kinin were compared.H-Phe-Phe-Ψ[CS-NH]-D-Ala-Trp-Gly-NH_2 and H-Phe-Tyr-Ψ[CS-N]- Pro-Trp-Gly-NH_2 were studied by UV-vis absorption.The isomerization energy barriers of the two segments,Ac-Phe-Ψ[CS-NH]- D-Ala-NH_2 and Ac-Tyr-Ψ[CS-N]-Pro-NH_2 picked from the two peptides,were calculated using ab initio method.The cis isomer of CS-N is more stable than th...
文摘The preparation and performance characterization of〈50 nm spirobenzopyran-based photochromic nanocomposites with photoswitchable fluorescence are presented.The nanocomposites were fabricated by means of a modifed miniemulsion polymerization process,in which the hydrophobic spirobenzopyran was covalently attached to the polymer chains and the matched fluorescent dyes were noncovalently embedded in the nanoscale cross-linked polymeric matrix,respectively.The obtained nanocomposites with a high relative fluorescence quantum yield（Q）exhibited superior fluorescent photoswitchable performance due to the effective photo-induced intermolecular energy transfer.The stability of photomerocyanine was also improved.
基金supported by NSFC/China(21788102,21636002,21622602,21875143,21908146,and 21908060)Shanghai Municipal Science and Technology Major Project(2018SHZDZX03)+3 种基金Innovation Program of Shanghai Municipal Education Commission,Scientific Committee of Shanghai(15XD1501400)Programme of Introducing Talents of Discipline to Universities(B16017)China Postdoctoral Science Foundation(2019M651417)Innovation Research Foundation of Shenzhen(JCYJ20180507182229597).
文摘Tetraphenylethene(TPE),a star building block with promising aggregationinduced emission,has received much interest.Given that its intramolecular Woodward-Hoffmann cyclic intermediate instantaneously converts back to the original state within several picoseconds,the essentially photochromic characteristic of TPE is little investigated.Achieving a visible photocyclization of TPE is still an unsolved issue and considered as the bottleneck in the further advancement of applications.We report a strategy of attaching carbonate ester onto the TPE skeleton(TPE-4C)to enhance TPE photocyclization stability.As demonstrated,the incorporated cholesteryloxycarbonyloxy substituents in TPE-4C can increase the energy barrier for cycloreversion,thereby exhibiting extremely thermal stability of photocyclic intermediate upon UV irradiation,prolonging its lifetime from 63 picoseconds to 46 s by 7.2×10^(11)-fold.The photoinduced cyclization of TPE-4C could be monitored with naked eyes,and the photocyclization/cycloreversion is achieved by turning on/off UV light along with a relative fatigue resistance.Encapsulation of TPE-4C into the liquid crystal can induce a striking phase transformation(achiral↔chiral),which can be applicable to encode optical information.Employing carbonate ester into the TPE unit plays a vital role in enhancing the unprecedented TPE photocyclization stability,providing a toolbox to allow TPE-based photocyclization to be visually monitored.
文摘1.Introduction The introduction of photoswitches into the bioactive substances is the fundamental idea behind photopharmacology.Upon light irradiation,the drug activity can be spatiotemporally controlled by the photon-induced variety of photoswitch's structures or characteristics[1].However,some challenges are still faced in photopharmacology including phototoxicity and limited tissue penetration depth(about a few millimeters).
文摘An interest in the fluorescent protein asFP595 is due to unexplained puzzles in its photophysical behavior. We report the results of calculations of structures, absorption, and emission bands in asFP595 by considering model molecular clusters in the coordinate-locking scheme. Both trans and cis conformations of the anionic chromophore are considered. Equilibrium geometry coordinates on the ground potential energy surface were optimized in the density functional theory approaches by considering both large- and reduced-size clusters. The cluster size was reduced to locate positions of the minimum energy points on the excited-state potential surface by using the configuration interaction singles approach. Vertical excitation energies and oscillator strengths were computed by using the ZINDO method. We show that consideration of large clusters mimicking the protein-containing pocket is an essential issue to calculate positions of absorption and emission bands with the accuracy compatible to experiments.
基金supported by the Qingdao Natural Science Foundation(23-2-1250-zyyd-jch)the National Natural Science Foundation of China(52173204)Cultivation Plan of Young Innovative Talents in Colleges and Universities of Shandong Province(2022KJ154)。
文摘Photoswitchable catalysis provides a non-invasive strategy for dynamically controlling light-driven chemical energy conversion processes.The defining advantage of photoswitchable catalytic systems lies in their unique dual capacity:i)spatiotemporal precision in resolving reactive species generation through optical addressing;and ii)adaptive multifunctionality enabling on-demand switching between distinct active phases,thereby suppressing competing pathways and eliminating undesired side reactions.
基金financial support from the National Natural Science Foundation of China(No.22374075)the Start-up Research Fund of Southeast University(4031002412).
文摘Recent advancements in single-molecule biophysics have been driven by breakthroughs in advanced fluorescence microscopy techniques and the development of nextgeneration organic fluorophores.These cutting-edge fluorophores,coupled through tailored biolabeling strategies,offer single-molecule brightness,photostability,and phototunability(i.e.,photoswitchable,photoactivatable),contributing to enhancing spatial and temporal imaging resolution for studying biomolecular interactions and dynamics at single-event precision.This review examines the progress made over the past decade in the development of next-generation fluorophores,along with their site-specific labeling methods for proteins,nucleic acids,and biomolecular complexes.It also explores their applications in single-molecule fluorescencebased dynamic structural biology and super-resolution microscopy imaging.Furthermore,it examines ongoing efforts to address challenges associated with fluorophore photostability,photobleaching,and the integration of advanced photophysical and photochemical functionalities.The integration of state-of-the-art fluorophores with advanced labeling strategies aim to deliver complementary correlative data,holding promise for revolutionizing single-molecule biophysics by pushing the boundaries of temporal and spatial imaging resolution to unprecedented limits.
基金NSFC(S(92156010,22071247,22471274,and 22401279)the Key Research Program of Frontier Sciences(QYZDB-SSW-SLHO3O)of CAS+1 种基金the Postdoctoral Fellowship Program of China Postdoctoral Science Foundation(GZC20241725)Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China(2021ZR112)for funding.
文摘The visible light-driven photoswitches are attracting widespread attention,but it is challenging to leverage their phototriggered structural changes to regulate dynamic bonds,assemblies,and materials.Herein,we incorporated reversible covalent sites of aldehyde ring-chain tautomers into all-visible-light azobenzenes toward a versatile platform for light-controlled formation/exchange of dynamic C—N bonds from secondary amines.The movement of ring-chain equilibrium was attained via manipulating intramolecular multiple hydrogen bonding from E/Z configurational isomers.Such structural regulation further enabled photocontrolled kinetics for the formation and exchange reactions of cyclic hemiaminal ethers from secondary amines exhibiting kinetic rate reversal from E/Z isomers.The varied capability of E/Z configurational isomers in engaging in multiple hydrogen bonds of azo attached carboxylate with ammonium salt accounts for the difference.Moreover,the photoswitching performance of azobenzenes in different solutions was readily regulated by dynamic covalent reactions with amines.The dynamic reactivity control with visible light and associated mechanistic foundation add into the collection of photoswitchable dynamic covalent chemistry and would lay the foundation for subsequent biological and material applications.
基金financially supported by the National Natural Science Foundation of China(grant nos.92156010,22071247,22101283,and 22101284)the Strategic Priority Research Program(grant no.XDB20000000)+1 种基金the Key Research Program of Frontier Sciences(grant no.QYZDB-SSW-SLH030)of Chinese Academy of Sciences,Natural Science Foundation of Fujian Province(grant nos.2020J06035 and 2022J05085)Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China(grant no.2021ZR112)for support.
文摘Molecular photoswitches hold an important position in chemical research,and it is of significance to develop novel structures and mechanisms.Herein we report a new type of E/Z photoswitches in tellurazole/tellurazolium-based olefin scaffolds,wherein intramolecular through-space n→π^(*)orbital interaction plays a stabilizing role in the Z isomer approaching quantitative conversion.The manipulation of diverse noncovalent interactions,including intermolecular chalcogen bonding,further provided versatile handles for regulating molecular recognition and multiaddressable switching.Despite bidirectional E/Z photoisomerization with neutral tellurazole derivatives,protonation-induced cationic tellurazoliums allowed significant enhancement in the efficiency of Z→E switching(E up to 73%)while maintaining high percentage E→Z switching(Z up to 95%),as chalcogen bonding with counteranions contributes to the stabilization of electron-accepting tellurazoliums affording a larger wavelength difference between E/Z isomers.Furthermore,the n→π^(*)orbital interaction enables the preference of Z isomer in the ground state for N-methyl tellurazoliums.Bidirectional E/Z photoswitching with high conversion(Z up to 99%,E up to 81%)was attained,and E→Z isomerization can also be invoked by nucleophilic catalysis,making N-methyl tellurazoliums as T-type photoswitches.The results showcase the power of noncovalent interactions for controlling molecular photoswitches and should set the scene for vip recognition,dynamic assemblies,and responsive materials.
文摘The wide application of photoswitches requires control over their isomerization dynamics.Utilizing noncovalent interactions is a promising strategy as it offers active regulation in-situ.However,this control strategy has not yet been explored in-depth to reach its full potential.In this work,we demonstrate that by directing noncovalent interactions to the central rotating bond of indigo-based photoswitches,their thermal relaxation dynamics were altered in two opposite directions(either slowed down or sped up)allowing for modulating the relaxation half-lives across four orders of magnitude.More importantly,our work established two distinct and orthogonal working mechanisms of noncovalent control over isomerization:(1)Thermodynamic stabilization of photoisomers;and(2)Facilitating an alternative reaction pathway through Brønsted/Lewis acid catalysis.This two-directional modulation(resembling agonists and inverse agonists in biological systems)via two orthogonal working mechanisms will enable more delicate manipulation of photoswitches for advanced applications.
基金support from the National Key Research and Development Program of China(No.2023YFB3609300)the National Natural Science Foundation of China(Nos.62205240 and 12274320)support from the Swedish Foundation for International Cooperation in Research and Higher Education(STINT IB2023-9189)。
文摘Modulating photoluminescent(PL)materials is crucial for applications such as super-resolution microscopy.The combination of PL materials and photoswitches can achieve this aim by utilizing isomerization of the photoswitches.Here we report an optically PL switchable system by mixing carbon quantum dots(CQDs)and diarylethene(DAE)molecular photoswitches.The PL on/off states of CQDs,switched with alternating visible and UV light,achieve a PL on/off ratio of500 and stable reversibility over 20 cycles.The mechanism of our design is revealed by PL lifetime measurements,temperature-dependent PL spectroscopy,and density functional theory(DFT)calculations,confirming that efficient static quenching and the inner filter effect between CQDs and closed DAEs are the keys to achieving such outstanding performance.
基金supported by the National Natural Science Foundation of China (21877011, 21576038, 21421005)the Fundamental Research Funds for the Central Universities of China (DUT16TD21)+1 种基金Science Program of Dalian City (2014J11JH133, 2015J12JH207)the Supercomputing Center of Dalian University of Technology
文摘Photochromic diarylethenes have been widely used in many fields. However, their cyclization process must be induced by UV light. In this article, a simple strategy is developed by extending π-conjugation with electron donating groups. The modified dirylethene derivative can photocyclolize under 405-nm light with a good photochromic efficiency. Meanwhile, its absorption and moderate fluorescence can be switched effectively in both directions by visible lights(405 and 520 nm, respectively) in different solutions and in living cells. We believe that this simple method will become a versatile strategy for developing various dirylethylenes with visible-light photochromism.
基金supported by the National Natural Science Foundation of China(Nos.11804387,11802339,11805276,11902358,61805282,and 61801498)the Scientific Researches Foundation of National University of Defense Technology(Nos.ZK18-03-22,ZK18-01-03,and ZK18-03-36)。
文摘Recently reported plasmon-induced transparency(PIT)in metamaterials endows the optical structures in classical systems with quantum optical effects.In particular,the nonreconfigurable nature in metamaterials makes multifunctional applications of PIT effects in terahertz communications and optical networks remain a great challenge.Here,we present an ultrafast process-selectable modulation of the PIT effect.By incorporating silicon islands into diatomic metamaterials,the PIT effect is modulated reversely,depending on the vertical and horizontal configurations,with giant modulation depths as high as 129%and 109%.Accompanied by the enormous switching of the transparent window,remarkable slow light effect occurs.
