Photosystem Ⅱ(PSⅡ)is a large membrane protein(∼700 kDa)complex,harboring P680+,the strongest oxidant known in biological systems,which is responsible for driving tyrosine oxidation and ultimately O_(2) generation.W...Photosystem Ⅱ(PSⅡ)is a large membrane protein(∼700 kDa)complex,harboring P680+,the strongest oxidant known in biological systems,which is responsible for driving tyrosine oxidation and ultimately O_(2) generation.While the enhancement and expansion of PSⅡ functions through genetic engineering would be beneficial for driving challenging chemical reactions,this has proven difficult due to its enormous complexity.Here,we report a genetically encoded,27 kDa photosensitizer protein(PSP3)that recapitulates the initial photoinduced key properties of PSⅡ.Through the genetic incorporation of benzophenone-alanine(BpA)into a fluorescent protein coupled with femtosecond transient absorption measurement,we show that photoinduced electron transfer from residue Tyr203 to the PSP3 chromophore occurs very rapidly(∼1 ps),which is comparable with that of the first electron transfer step in PSII.Since PSP3 can be overexpressed in high yield in Escherichia coli and genetically engineered easily,it might facilitate challenging oxidation and reduction reactions in vitro and in vivo.展开更多
Light-responsive proton conductors might find applications in both traditional fields(fuel cells,chemical sensors,bio-ionic functions,etc.)and modern high-speed switchable smart systems(Internet of things,robotics,etc...Light-responsive proton conductors might find applications in both traditional fields(fuel cells,chemical sensors,bio-ionic functions,etc.)and modern high-speed switchable smart systems(Internet of things,robotics,etc.).Previous synthetic methods resulted in low switching contrasts(<two times)or they tended to be limited significantly in solid matrixes due to large structural changes.The photoinduced electron-transfer(PIET)method avoids the influence of stereo space in solid matrixes and capable of achieving high switching contrasts.For the first time,we applied the PIET strategy to design lightresponsive proton conductors to achieve the hitherto largest gain of proton conductivity(ca.54 times)for light-responsive proton conductors in one crystalline photochromic viologen-based H-bonded supramolecule.The weakening of hydrogen-bonding interactions in the proton-transport path after PIET accounted for an increased proton conductivity.These findings would inspire the exploration of photon conductors that display higher proton conductivities or switchable smart systems with high contrasts.展开更多
A series of aromatic imines were reduced to corresponding amines in excellent yields by 2-phenyl-N, N-dimethylbenzimidazoline (PDMBI) photochemically in the presence of magnesium perchloride (Mg(ClO4)2). A Mg2+ mediat...A series of aromatic imines were reduced to corresponding amines in excellent yields by 2-phenyl-N, N-dimethylbenzimidazoline (PDMBI) photochemically in the presence of magnesium perchloride (Mg(ClO4)2). A Mg2+ mediated photoinduced electron transfer mechanism was proposed.展开更多
A photochemical desilylation reaction with nearly quantitative yield and excellent selectivity between silyl alkyl ether and silyl enol ether is reported.
A novel polyurethane polymer containing perylene diimide(PDI)unit and aniline segment,denoted as PU-PDI,was designed and synthesized.Their tensile property and photophysical characteristic were investigated using vari...A novel polyurethane polymer containing perylene diimide(PDI)unit and aniline segment,denoted as PU-PDI,was designed and synthesized.Their tensile property and photophysical characteristic were investigated using various experimental and theoretical techniques.It is found that the elongation of PU-PDIs can reach more than 1000%,indicating good tensile performance.Moreover,based on the photoinduced electron transfer mechanism,the aniline segments in polyurethane can quench the auto-fluorescence of PDI unit to a negligible value,which overcomes the intractable fluorescence drawbacks of conventional colour filters.The non-emissive characteristic,in combination with the good thermal stability and tensile property of PU-PDI,provides a feasible design strategy to fabricate optical filters with high display quality.展开更多
An efficient PET-based probe,in which the ferrocene quencher and the naphthalimide fluorophore are linked by a disulfide bond,has been developed.This probe can be activated by GSH with fluorescence a turn-on response ...An efficient PET-based probe,in which the ferrocene quencher and the naphthalimide fluorophore are linked by a disulfide bond,has been developed.This probe can be activated by GSH with fluorescence a turn-on response for blocking the PET process.In addition,it was successfully applied for distinguishing cancer cells from normal cells。展开更多
Excessive mercury ions(Hg^(2+)) in the environment can accumulate in human body along with the food chain to cause serious physiological reactions.The fluorescence probes were considered as convenient tool with great ...Excessive mercury ions(Hg^(2+)) in the environment can accumulate in human body along with the food chain to cause serious physiological reactions.The fluorescence probes were considered as convenient tool with great potential for Hg^(2+) detection.Most existing probes suffer from aggregation-induced quenching(ACQ) effects and insufficient sensitivity.Herein,a novel type of fluorophore was developed by combining the aggregation-induced emission(AIE) and excited state intramolecular proton transfer(ESIPT) characteristics.Subsequently,a phenyl thioformate group with photoinduced electron transfer(PET)effect was connected to give an efficient "turn-on" probe(HTM),which exhibited good selectivity toward Hg^(2+),short response time(30 min),coupled with extremely low detection limit(LOD=1.68 nmol/L).In addition,HTM was used successfully in real samples,cells and drug evaluation,underlying the superiority of HTM to detect Hg^(2+) in practical applications.展开更多
Sable organic radicals are promising materials for information storage,molecular magnetism,electronic devices,and biological probes.Many organic radicals have been prepared,but most are non-or weakly emissive and degr...Sable organic radicals are promising materials for information storage,molecular magnetism,electronic devices,and biological probes.Many organic radicals have been prepared,but most are non-or weakly emissive and degrade easily upon photoexcitation.It remains challenging to produce stable and efficient luminescent radicals because of the absence of general guidelines for their synthesis.Herein,we present a photoactivation approach to generate a stable luminescent radical from tris(4-chlorophenyl)phosph ine(TCPP)with red emission in the crystal state.The mechanistic study suggests that the molecular symmetry breaking in the crystal causes changes of molecular conformation,redox properties,andmolecular packing that facilitates radical generation and stabilization.This design strategy demonstrates a straightforward approach to develop stable organic luminescent radicals that will open new doors to photoinduced luminescent radical materials.展开更多
基金financially supported by the National Key Research and Development Program of China under award nos.2016YFA0501502 and 2017YFA0503704the National Science Foundation of China under award nos.91940306,21837005,21890743,21961142014,21750003,91527302,and 21827803+2 种基金pilot project of CAS under award no.XDB37040203the Sanming Project of Medicine in Shenzhen(no.Y8KF351001)the Youth Innovation Promotion Association CAS.
文摘Photosystem Ⅱ(PSⅡ)is a large membrane protein(∼700 kDa)complex,harboring P680+,the strongest oxidant known in biological systems,which is responsible for driving tyrosine oxidation and ultimately O_(2) generation.While the enhancement and expansion of PSⅡ functions through genetic engineering would be beneficial for driving challenging chemical reactions,this has proven difficult due to its enormous complexity.Here,we report a genetically encoded,27 kDa photosensitizer protein(PSP3)that recapitulates the initial photoinduced key properties of PSⅡ.Through the genetic incorporation of benzophenone-alanine(BpA)into a fluorescent protein coupled with femtosecond transient absorption measurement,we show that photoinduced electron transfer from residue Tyr203 to the PSP3 chromophore occurs very rapidly(∼1 ps),which is comparable with that of the first electron transfer step in PSII.Since PSP3 can be overexpressed in high yield in Escherichia coli and genetically engineered easily,it might facilitate challenging oxidation and reduction reactions in vitro and in vivo.
基金supported by the National Natural Science Foundation of China(nos.91545201,21827813,22001011,and 22001037)the Strategic Priority Research Program of the Chinese Academy of Sciences(nos.XDB20010100 and YJKYYQ20180006)the Key Research Program of Frontier Science,Chinese Academy of Sciences(no.QYZDB-SSW-SLH020).
文摘Light-responsive proton conductors might find applications in both traditional fields(fuel cells,chemical sensors,bio-ionic functions,etc.)and modern high-speed switchable smart systems(Internet of things,robotics,etc.).Previous synthetic methods resulted in low switching contrasts(<two times)or they tended to be limited significantly in solid matrixes due to large structural changes.The photoinduced electron-transfer(PIET)method avoids the influence of stereo space in solid matrixes and capable of achieving high switching contrasts.For the first time,we applied the PIET strategy to design lightresponsive proton conductors to achieve the hitherto largest gain of proton conductivity(ca.54 times)for light-responsive proton conductors in one crystalline photochromic viologen-based H-bonded supramolecule.The weakening of hydrogen-bonding interactions in the proton-transport path after PIET accounted for an increased proton conductivity.These findings would inspire the exploration of photon conductors that display higher proton conductivities or switchable smart systems with high contrasts.
基金The authors thank the National Natural Science Foundation of China (Grant No. 29972018) for financial support.
文摘A series of aromatic imines were reduced to corresponding amines in excellent yields by 2-phenyl-N, N-dimethylbenzimidazoline (PDMBI) photochemically in the presence of magnesium perchloride (Mg(ClO4)2). A Mg2+ mediated photoinduced electron transfer mechanism was proposed.
基金the National Natural Science Foundation of China (Grant No. 29972018) for financial support.
文摘A photochemical desilylation reaction with nearly quantitative yield and excellent selectivity between silyl alkyl ether and silyl enol ether is reported.
基金supported by the National Natural Science Foundation of China(Grant Nos.21875157,22175129)the China Education Association for International Exchange(CEAlE)(No.2021102)the open foundation of State Key Laboratory of Chemical Engineering(No.SKL-ChE-20B04).
文摘A novel polyurethane polymer containing perylene diimide(PDI)unit and aniline segment,denoted as PU-PDI,was designed and synthesized.Their tensile property and photophysical characteristic were investigated using various experimental and theoretical techniques.It is found that the elongation of PU-PDIs can reach more than 1000%,indicating good tensile performance.Moreover,based on the photoinduced electron transfer mechanism,the aniline segments in polyurethane can quench the auto-fluorescence of PDI unit to a negligible value,which overcomes the intractable fluorescence drawbacks of conventional colour filters.The non-emissive characteristic,in combination with the good thermal stability and tensile property of PU-PDI,provides a feasible design strategy to fabricate optical filters with high display quality.
基金supported by the National Nature Science Foundation of China(Nos.21762028 and 21462027)the Nature Science Foundation of Jiangxi Province of China(No.20172BCB22007),which are greatly acknowledged by the authors。
文摘An efficient PET-based probe,in which the ferrocene quencher and the naphthalimide fluorophore are linked by a disulfide bond,has been developed.This probe can be activated by GSH with fluorescence a turn-on response for blocking the PET process.In addition,it was successfully applied for distinguishing cancer cells from normal cells。
基金financial supports from the National Natural Science Foundation of China (Nos. 81971678 and 81671756)the Innovation Fund for Post graduate Students of Central South University (No. 2020zzts827)。
文摘Excessive mercury ions(Hg^(2+)) in the environment can accumulate in human body along with the food chain to cause serious physiological reactions.The fluorescence probes were considered as convenient tool with great potential for Hg^(2+) detection.Most existing probes suffer from aggregation-induced quenching(ACQ) effects and insufficient sensitivity.Herein,a novel type of fluorophore was developed by combining the aggregation-induced emission(AIE) and excited state intramolecular proton transfer(ESIPT) characteristics.Subsequently,a phenyl thioformate group with photoinduced electron transfer(PET)effect was connected to give an efficient "turn-on" probe(HTM),which exhibited good selectivity toward Hg^(2+),short response time(30 min),coupled with extremely low detection limit(LOD=1.68 nmol/L).In addition,HTM was used successfully in real samples,cells and drug evaluation,underlying the superiority of HTM to detect Hg^(2+) in practical applications.
基金financially supported by theNationalNatural Science Foundation of China(grant no.21788102)the NaturalScienceFoundationofGuangdongProvince(grant nos.2019B121205002 and 2019B030301003)+3 种基金the Research Grants Council of Hong Kong(grant nos.16305618,16305518,C6014-20W,C6009-17G,and AoE/P-02/12)the National Key Research and Development Program(grant no.2018YFE0190200)the Innovation and Technology Commission(grant no.ITC-CNERC14SC01)the Science and Technology Plan of Shenzhen(grant nos.JCYJ20180306174910791,JCYJ20170818113530705,JCY J20170818113538482,and JCYJ20160229205601482).
文摘Sable organic radicals are promising materials for information storage,molecular magnetism,electronic devices,and biological probes.Many organic radicals have been prepared,but most are non-or weakly emissive and degrade easily upon photoexcitation.It remains challenging to produce stable and efficient luminescent radicals because of the absence of general guidelines for their synthesis.Herein,we present a photoactivation approach to generate a stable luminescent radical from tris(4-chlorophenyl)phosph ine(TCPP)with red emission in the crystal state.The mechanistic study suggests that the molecular symmetry breaking in the crystal causes changes of molecular conformation,redox properties,andmolecular packing that facilitates radical generation and stabilization.This design strategy demonstrates a straightforward approach to develop stable organic luminescent radicals that will open new doors to photoinduced luminescent radical materials.
