The development of molecular probes or systems with the ability of multiple orthogonal responses is an effective approach to precisely detect biomolecules with similar chemical structures.Herein,we report the synthesi...The development of molecular probes or systems with the ability of multiple orthogonal responses is an effective approach to precisely detect biomolecules with similar chemical structures.Herein,we report the synthesis of a water-soluble TPE-based octacationic cage(1)with the compressed TPE-containing bilayer,which endows it with good fluorescence properties and potential conformation chirality.As a result,1 exhibits molecular recognition for anionic nucleotides within its two“claw”-like cavities to form 1:2 host-vip complexes in water,companying with selective turn-off fluorescence and turn-on CD responses to G/GTP over other nucleotides.展开更多
Photodynamic therapy(PDT)is a promising noninvasive method for targeted cancer cell destruction.Still,its effectiveness is often hindered by the aggregation-caused quenching effect of organic photosensitizer(PS)in aqu...Photodynamic therapy(PDT)is a promising noninvasive method for targeted cancer cell destruction.Still,its effectiveness is often hindered by the aggregation-caused quenching effect of organic photosensitizer(PS)in aqueous environments.Here,we have employed a combination of covalent and noncovalent restricted-intramolecularrotation strategies to develop supramolecular PSs with aggregation-induced emission(AIE)characteristics.Firstly,a water-soluble octacationic molecular cage(1)with a bilayer tetraphenylethene(TPE)structure has been designed and synthesized,which minimizes intramolecular rotation of TPE moieties and achieves the single-molecule-level aggregation by the covalent restriction of intramolecular rotation(RIR)via molecular engineering synthesis.Compared with its single-layer TPE analog,1 exhibits superior efficiency in generating reactive oxygen species(ROS)including superoxide radical(O2−•)and singlet oxygen(1O2)upon whitelight irradiation.Subsequently,by forming a 1:4 host–vip complex(1@CB[8]4)between 1 and cucurbit[8]uril(CB[8]),O2−•generation can be further enhanced by the noncovalent RIR via the host–vip assembly.Additionally,1@CB[8]4 as a photocatalyst promotes rapid oxidation of nicotinamide adenine dinucleotide(NADH)in water.Given its Type-I ROS generation and catalytic activity for NADH oxidation,1@CB[8]4 acts as a supramolecular AIE-type PS to exhibit strong photo-induced cytotoxicity upon white-light irradiation under hypoxic conditions,showcasing its potential for synergistic PDT.展开更多
The design and development of selective recognition and sensing systems for biologically important nucleoside triphosphates(NTPs)have attracted significant attention in recent years,owing to their critical roles in ce...The design and development of selective recognition and sensing systems for biologically important nucleoside triphosphates(NTPs)have attracted significant attention in recent years,owing to their critical roles in cellular processes.In this study,we report the synthesis of two tetraphenylethene-based tetraimidazolium cyclophanes(1 and 2)through a one-step S_(N)2 reaction.These cyclophanes are capable of recognizing NTPs by forming stable 1:1 host-vip complexes in aqueous solution.Of particular interest,cyclophane 1 demonstrates exceptional selectivity for guanosine triphosphate(GTP),distinguishing it from other nucleoside triphosphates such as ATP,CTP,and UTP.This selective recognition is accompanied by distinct and measurable fluorescence responses,which are significantly enhanced upon binding to GTp,enabling the potential for sensitive detection.This study highlights the potential of tetraphenylethene-based tetraimidazolium cyclophanes as a highly selective and sensitive sensor for GTP,offering new insights into the design of molecular systems for the recognition of biologically relevant nucleotides.展开更多
Porphyrins and their derivatives,such as peroxidases,hemoglobin,cytochromes,and chlorophylls,play essential roles in biological processes,particularly within photosystem Ⅰ and Ⅱ.Inspired by nature,we present a simpl...Porphyrins and their derivatives,such as peroxidases,hemoglobin,cytochromes,and chlorophylls,play essential roles in biological processes,particularly within photosystem Ⅰ and Ⅱ.Inspired by nature,we present a simple and effective strategy for constructing a porphyrin-based supramolecular system to enhance the photosensitizing efficiency of porphyrins through a coordination-driven self-assembly process.In this work,a monofunctionalized tetraphenylethene(TPE)-based cage(1)with a pyridine group and a hydrophobic cavity was designed and synthesized.This covalent molecular cage can interact with zinc tetraphenyl porphyrin(2)through axial coordination of pyridine with the zinc ion,forming a coordinated complex(3).In solution,the ditopic complex 3,with both host and vip moieties,spontaneously assembles into a cyclic[c2]daisy chain(3_(2)).The self-assembly of 3_(2) combines the advantages of TPE and porphyrin units,leading to improved charge separation,efficient intersystem crossing,and stable triplet states.These features highly enhance the generation of reactive oxygen species(ROS).As a result,3_(2),as a photocatalyst,exhibits rapid catalytic oxidation of nicotinamide adenine dinucleotide(NADH),with a high turnover frequency of 13.4 min^(−1).By combining the cytotoxic effects of ROS and the disruption of the intracellular redox balance involving NADH,3_(2) functions as a supramolecular photosensitizer that demonstrates effective photodynamic therapy with good biocompatibility and biosafety in a hypoxic environment.展开更多
基金the National Natural Science Foundation of China(Nos.22122108 and 21971208)the Natural Science Basic Research Plan for Distinguished Young Scholars in Shaanxi Province of China(No.2021JC-37)the Fok Ying Tong Education Foundation(No.171010).
文摘The development of molecular probes or systems with the ability of multiple orthogonal responses is an effective approach to precisely detect biomolecules with similar chemical structures.Herein,we report the synthesis of a water-soluble TPE-based octacationic cage(1)with the compressed TPE-containing bilayer,which endows it with good fluorescence properties and potential conformation chirality.As a result,1 exhibits molecular recognition for anionic nucleotides within its two“claw”-like cavities to form 1:2 host-vip complexes in water,companying with selective turn-off fluorescence and turn-on CD responses to G/GTP over other nucleotides.
基金Fok Ying Tong Education Foundation,Grant/Award Number:171010Natural Science Basic Research Plan for Distinguished Young Scholars in Shaanxi Province of China,Grant/Award Number:2021JC-37+1 种基金Northwestern University 2024 Excellent Doctoral Dissertation Cultivation Project,Grant/Award Number:YB2024011National Natural Science Foundation of China,Grant/Award Numbers:22122108,22371229,21975197。
文摘Photodynamic therapy(PDT)is a promising noninvasive method for targeted cancer cell destruction.Still,its effectiveness is often hindered by the aggregation-caused quenching effect of organic photosensitizer(PS)in aqueous environments.Here,we have employed a combination of covalent and noncovalent restricted-intramolecularrotation strategies to develop supramolecular PSs with aggregation-induced emission(AIE)characteristics.Firstly,a water-soluble octacationic molecular cage(1)with a bilayer tetraphenylethene(TPE)structure has been designed and synthesized,which minimizes intramolecular rotation of TPE moieties and achieves the single-molecule-level aggregation by the covalent restriction of intramolecular rotation(RIR)via molecular engineering synthesis.Compared with its single-layer TPE analog,1 exhibits superior efficiency in generating reactive oxygen species(ROS)including superoxide radical(O2−•)and singlet oxygen(1O2)upon whitelight irradiation.Subsequently,by forming a 1:4 host–vip complex(1@CB[8]4)between 1 and cucurbit[8]uril(CB[8]),O2−•generation can be further enhanced by the noncovalent RIR via the host–vip assembly.Additionally,1@CB[8]4 as a photocatalyst promotes rapid oxidation of nicotinamide adenine dinucleotide(NADH)in water.Given its Type-I ROS generation and catalytic activity for NADH oxidation,1@CB[8]4 acts as a supramolecular AIE-type PS to exhibit strong photo-induced cytotoxicity upon white-light irradiation under hypoxic conditions,showcasing its potential for synergistic PDT.
基金supported by the National Natural Science Foundation of China(Nos.22301241 and 22371229)the Shaanxi Fundamental Science Research Project for Chemistry and Biology(22JHQ073).
文摘The design and development of selective recognition and sensing systems for biologically important nucleoside triphosphates(NTPs)have attracted significant attention in recent years,owing to their critical roles in cellular processes.In this study,we report the synthesis of two tetraphenylethene-based tetraimidazolium cyclophanes(1 and 2)through a one-step S_(N)2 reaction.These cyclophanes are capable of recognizing NTPs by forming stable 1:1 host-vip complexes in aqueous solution.Of particular interest,cyclophane 1 demonstrates exceptional selectivity for guanosine triphosphate(GTP),distinguishing it from other nucleoside triphosphates such as ATP,CTP,and UTP.This selective recognition is accompanied by distinct and measurable fluorescence responses,which are significantly enhanced upon binding to GTp,enabling the potential for sensitive detection.This study highlights the potential of tetraphenylethene-based tetraimidazolium cyclophanes as a highly selective and sensitive sensor for GTP,offering new insights into the design of molecular systems for the recognition of biologically relevant nucleotides.
基金supported by the National Natural Science Foundation of China(grant nos.22371229 and 22301241)the National Key R&D Program of China,Synthetic Biology Research(grant no.2023YFA0913600).
文摘Porphyrins and their derivatives,such as peroxidases,hemoglobin,cytochromes,and chlorophylls,play essential roles in biological processes,particularly within photosystem Ⅰ and Ⅱ.Inspired by nature,we present a simple and effective strategy for constructing a porphyrin-based supramolecular system to enhance the photosensitizing efficiency of porphyrins through a coordination-driven self-assembly process.In this work,a monofunctionalized tetraphenylethene(TPE)-based cage(1)with a pyridine group and a hydrophobic cavity was designed and synthesized.This covalent molecular cage can interact with zinc tetraphenyl porphyrin(2)through axial coordination of pyridine with the zinc ion,forming a coordinated complex(3).In solution,the ditopic complex 3,with both host and vip moieties,spontaneously assembles into a cyclic[c2]daisy chain(3_(2)).The self-assembly of 3_(2) combines the advantages of TPE and porphyrin units,leading to improved charge separation,efficient intersystem crossing,and stable triplet states.These features highly enhance the generation of reactive oxygen species(ROS).As a result,3_(2),as a photocatalyst,exhibits rapid catalytic oxidation of nicotinamide adenine dinucleotide(NADH),with a high turnover frequency of 13.4 min^(−1).By combining the cytotoxic effects of ROS and the disruption of the intracellular redox balance involving NADH,3_(2) functions as a supramolecular photosensitizer that demonstrates effective photodynamic therapy with good biocompatibility and biosafety in a hypoxic environment.
