There is a strong climate gradient in the Inner Mongolia region, China, with solar radiation and air temperature increasing but precipitation decreasing gradually from the northeast to the southwest. Sixteen Cara- gan...There is a strong climate gradient in the Inner Mongolia region, China, with solar radiation and air temperature increasing but precipitation decreasing gradually from the northeast to the southwest. Sixteen Cara- gana species exist in the Inner Mongolia region. These Caragana species exhibit a distribution pattern across moisture zones and form a geographical replacement series. In order to examine the mechanisms responsible for Caragana species distribution pattern, we selected 12 Caragana species that exhibit a distinct distribution pattern across multiple moisture zones in the Inner Mongolia region, and determined the relationships between the leaf ecological and physiological traits of these Caragana species and the aridity index and solar radiation. Along with the climatic drought gradient and the solar radiation intensification from the northeast to the southwest, leaf eco- logical characteristics of Caragana species changed drastically, i.e. the leaf shape gradually turned from flat into tegular or tubbish; the leaf hair became denser, longer and lighter in color; the leaf area, leaf biomass and specific leaf area （SLA） decreased significantly; the leaf thickness and the ratio of leaf thickness to leaf area increased sig- nificantly; and the leaf chlorophyll content decreased significantly. As the climatic drought stress increased, osmotic potentials of the main osmotic adjustment substances and the cytoplasmic ion concentration of Caragana species increased significantly. Meanwhile, the total and free water contents and water potential of leaves decreased sig- nificantly; the ratio of bound to free water increased significantly; the stomatal conductance and transpiration rate reduced significantly; and the water use efficiency （WUE） increased significantly. In addition, with the intensification of climatic drought stress, peroxidase （POD） and superoxide dismutase （SOD） activities in leaves increased significantly. As a result, the malondialdehyde （MDA） content increased while the oxygen free radical content decreased. Our results showed that most of the leaf ecological and physiological traits of the 12 Caragana species varied in accordance with the climatic drought gradient in the Inner Mongolia region, which reflected the adaptation of the Caragana species to the local climate conditions. With relatively more active metabolism and faster growth, the Caragana species in the northeast had strong competitive abilities; on the other hand, with stronger resistance to climatic drought stress, the Caragana species in the southwest could survive in harsh environments. Based on our results, we con- cluded that both the environmental gradients and the adaptive responses of Caragana species to their environments played important roles in the formation of the Caragana species distribution pattern across the Inner Mongolia region.展开更多
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
MEA aqueous solution is widely utilized as an absorbent in chemical absorption processes.However,it is challenged by many disadvantages,including low regeneration capacity and high energy consumption during regenerati...MEA aqueous solution is widely utilized as an absorbent in chemical absorption processes.However,it is challenged by many disadvantages,including low regeneration capacity and high energy consumption during regeneration.In this study,new no-aqueous MEA absorbents were prepared using alcohol ether organic solvents,including proprylene glycol monomethyl ether(PGME),ethylene glycol butyl ether(EGBE),poly(ethylene glycol)dimethyl ether(NHD)and diethylene glycol monoethyl Ether(DGME).Then the performance of the absorbents was assessed through a series of experiments and based on the results,a comparison was made between the non-aqueous absorbents to the conventional absorbent(30%(mass)MEA aqueous solution).It was found that the organic solvent system presented a higher CO_(2)removal efficiency than the MEA-H_(2)O system in the first 350 s,with the maximum enhancement ranging from 5.16%to 14.36%.While NHD improved the CO_(2)loading but reduced the regeneration efficiency.Except for the MEA-NHD system,all the other no-aqueous absorbents possessed a better regeneration efficiency than the MEA aqueous solution,which offers them the potential for industrial application.According to the data from NMR and FTIR analysis,after CO_(2)absorption,the products in the MEA-EGBE and MEA-DGME systems were mainly found in the lower phase,the other phase was mainly organic solvents.Therefore,only the lower phase needs to be treated during desorption,with the upper phase being recycled directly,thus reducing energy consumption.The use of alcohol ether organic solvents can improve the CO_(2)capture performance of absorbents to a certain extent and enhance their regeneration ability,providing a new direction for the subsequent research of non-aqueous absorbents.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
Functional dicyclophanes with various substituents(e.g.,NO_(2),Br,OCH_(3)and OH)were synthesized via one-pot S_(N)2 reaction.Dicyclophanes can form nanospheres via the head-to-tail self-assembly between the cavities a...Functional dicyclophanes with various substituents(e.g.,NO_(2),Br,OCH_(3)and OH)were synthesized via one-pot S_(N)2 reaction.Dicyclophanes can form nanospheres via the head-to-tail self-assembly between the cavities and the TPE units to exhibit aggregation-induced emission(AIE)in aqueous solution.These AIE-active nanospheres with cationic feature exhibited selective recognition with fluorescence response for anionic ATP via electrostatic interactions and hydrophobic effects in water.展开更多
Head and neck cancer(HNC)is malignant,genetically complex and difficult to treat and is the sixth most frequent cancer,with tobacco,alcohol and human papillomavirus being major risk factors.Based on epigenetic data,HN...Head and neck cancer(HNC)is malignant,genetically complex and difficult to treat and is the sixth most frequent cancer,with tobacco,alcohol and human papillomavirus being major risk factors.Based on epigenetic data,HNC is remarkably heterogeneous,and treatment remains challenging.There is a lack of significant improvement in survival and quality of life in patients with HNC.Over half of HNC patients experience locoregional recurrence or distal metastasis despite the current multiple traditional therapeutic strategies and immunotherapy.In addition,resistance to chemotherapy,radiotherapy and some targeted therapies is common.Therefore,it is urgent to explore more effective and tolerable targeted therapies to improve the clinical outcomes of HNC patients.Recent targeted therapy studies have focused on identifying promising biomarkers and developing more effective targeted therapies.A well understanding of the pathogenesis of HNC contributes to learning more about its inner association,which provides novel insight into the development of small molecule inhibitors.In this review,we summarized the vital signaling pathways and discussed the current potential therapeutic targets against critical molecules in HNC,as well as presenting preclinical animal models and ongoing or completed clinical studies about targeted therapy,which may contribute to a more favorable prognosis of HNC.Targeted therapy in combination with other therapies and its limitations were also discussed.展开更多
The hydrogen-bonded(H-bonded)base pairs,double H-bonded A•T and triple H-bonded G•C in DNA,are important units for storing,encoding,and expressing genetic information.Owing to the interference from water,however,the f...The hydrogen-bonded(H-bonded)base pairs,double H-bonded A•T and triple H-bonded G•C in DNA,are important units for storing,encoding,and expressing genetic information.Owing to the interference from water,however,the formation of H-bonded base pairs from short deoxynucleotide fragments such as mono-or di-deoxynucleotide are not easily achieved in aqueous solutions.展开更多
Ovarian cancer is the tumor with the highest mortality among gynecological malig-nancies.Studies have confirmed that paclitaxel chemoresistance is associated with increased infiltration of tumor-associated macrophages...Ovarian cancer is the tumor with the highest mortality among gynecological malig-nancies.Studies have confirmed that paclitaxel chemoresistance is associated with increased infiltration of tumor-associated macrophages(TAMs)in the microenvironment.Colony-stimu-lating factor 1(CSF-1)receptor(CSF-1R)plays a key role in regulating the number and differ-entiation of macrophages in certain solid tumors.There are few reports on the effects of targeted inhibition of CSF-1R in combination with chemotherapy on ovarian cancer and the tu-mor microenvironment.Here,we explored the antitumor efficacy and possible mechanisms of the CSF-1R inhibitor pexidartinib(PLX3397)when combined with the first-line chemothera-peutic agent paclitaxel in the treatment of ovarian cancer.We found that CSF-1R is highly ex-pressed in ovarian cancer cells and correlates with poor prognosis.Treatment by PLX3397 in combination with paclitaxel significantly inhibited the growth of ovarian cancer both in vitro and in vivo.Blockade of CSF-1R altered the macrophage phenotype and reprogrammed the immunosuppressive cell population in the tumor microenvironment.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
To the Editor:Current therapeutic strategies against breast cancer are limited by poor prognosis and unwanted side effects,especially in triple-negative breast cancer(TNBC).Ginkgetin(Gk),a natural,non-toxic bioflavono...To the Editor:Current therapeutic strategies against breast cancer are limited by poor prognosis and unwanted side effects,especially in triple-negative breast cancer(TNBC).Ginkgetin(Gk),a natural,non-toxic bioflavonoid extracted from Ginkgo biloba leaves,is a promising therapeutic candidate against breast cancer,[1]but the underlying mechanisms remain obscure.展开更多
Functional framework materials have been developed for many applications including adsorption, asymmetric catalysis, sensing,drug delivery, optical device, and so on. Here, we report the successive construction of two...Functional framework materials have been developed for many applications including adsorption, asymmetric catalysis, sensing,drug delivery, optical device, and so on. Here, we report the successive construction of two cucurbit[8]uril-based covalent organic frameworks(COFs) including tetraphenylethene-based COF(COF-1) and phenanthrene-based COF(COF-2) from a two-dimensional(2D) periodic cucurbit[8]uril-based supramolecular organic framework(SOF-1) as the prearranged structure via the intermolecular photocycloaddition of the coumarin units and the intramolecular photocyclization of the tetraphenylethene(TPE) units under ultraviolet(UV) irradiation(365 nm) in water. In this case, oxygen(O_(2)) plays an important role in the photocyclization of the TPE units into the phenanthrene units in the transform process from SOF-1 or COF-1 to COF-2. As the TPE units further form phenanthrenes after UV-irradiation, COF-2 exhibits aggregation-caused quenching effect and weak green emission, while COF-1 displays a strong yellow emission due to the aggregation-induced emission. Besides, the adaptive chirality of cationic COF-1 as a biomolecular sensor can be efficiently induced by chiral anionic biomolecules including adenosine-5′-triphosphate(ATP) and adenosine-5′-diphosphate(ADP) to exhibit sensitive negative circular dichroism responses in water. This supramolecular approach to construct COF from SOF via photochemical reactions may open a new opportunity for the construction and application of the water-soluble COFs with well structural controllability, unique photophysical properties,and favorable biocompatibility.展开更多
基金funded by the National Natural Science Foundation of China (31170381, 31100330)the National Basic Research Program of China (2007CB106802)
文摘There is a strong climate gradient in the Inner Mongolia region, China, with solar radiation and air temperature increasing but precipitation decreasing gradually from the northeast to the southwest. Sixteen Cara- gana species exist in the Inner Mongolia region. These Caragana species exhibit a distribution pattern across moisture zones and form a geographical replacement series. In order to examine the mechanisms responsible for Caragana species distribution pattern, we selected 12 Caragana species that exhibit a distinct distribution pattern across multiple moisture zones in the Inner Mongolia region, and determined the relationships between the leaf ecological and physiological traits of these Caragana species and the aridity index and solar radiation. Along with the climatic drought gradient and the solar radiation intensification from the northeast to the southwest, leaf eco- logical characteristics of Caragana species changed drastically, i.e. the leaf shape gradually turned from flat into tegular or tubbish; the leaf hair became denser, longer and lighter in color; the leaf area, leaf biomass and specific leaf area （SLA） decreased significantly; the leaf thickness and the ratio of leaf thickness to leaf area increased sig- nificantly; and the leaf chlorophyll content decreased significantly. As the climatic drought stress increased, osmotic potentials of the main osmotic adjustment substances and the cytoplasmic ion concentration of Caragana species increased significantly. Meanwhile, the total and free water contents and water potential of leaves decreased sig- nificantly; the ratio of bound to free water increased significantly; the stomatal conductance and transpiration rate reduced significantly; and the water use efficiency （WUE） increased significantly. In addition, with the intensification of climatic drought stress, peroxidase （POD） and superoxide dismutase （SOD） activities in leaves increased significantly. As a result, the malondialdehyde （MDA） content increased while the oxygen free radical content decreased. Our results showed that most of the leaf ecological and physiological traits of the 12 Caragana species varied in accordance with the climatic drought gradient in the Inner Mongolia region, which reflected the adaptation of the Caragana species to the local climate conditions. With relatively more active metabolism and faster growth, the Caragana species in the northeast had strong competitive abilities; on the other hand, with stronger resistance to climatic drought stress, the Caragana species in the southwest could survive in harsh environments. Based on our results, we con- cluded that both the environmental gradients and the adaptive responses of Caragana species to their environments played important roles in the formation of the Caragana species distribution pattern across the Inner Mongolia region.
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supported by National Key Research and Development Program(2022YFE0130000)the Xuzhou Science and Technology Plan Project(KC23077)+1 种基金the Fundamental Research Funds for the Central Universities(2023KYJD1005)the Natural Science Foundation of Jiangsu Province(BK20240208)。
文摘MEA aqueous solution is widely utilized as an absorbent in chemical absorption processes.However,it is challenged by many disadvantages,including low regeneration capacity and high energy consumption during regeneration.In this study,new no-aqueous MEA absorbents were prepared using alcohol ether organic solvents,including proprylene glycol monomethyl ether(PGME),ethylene glycol butyl ether(EGBE),poly(ethylene glycol)dimethyl ether(NHD)and diethylene glycol monoethyl Ether(DGME).Then the performance of the absorbents was assessed through a series of experiments and based on the results,a comparison was made between the non-aqueous absorbents to the conventional absorbent(30%(mass)MEA aqueous solution).It was found that the organic solvent system presented a higher CO_(2)removal efficiency than the MEA-H_(2)O system in the first 350 s,with the maximum enhancement ranging from 5.16%to 14.36%.While NHD improved the CO_(2)loading but reduced the regeneration efficiency.Except for the MEA-NHD system,all the other no-aqueous absorbents possessed a better regeneration efficiency than the MEA aqueous solution,which offers them the potential for industrial application.According to the data from NMR and FTIR analysis,after CO_(2)absorption,the products in the MEA-EGBE and MEA-DGME systems were mainly found in the lower phase,the other phase was mainly organic solvents.Therefore,only the lower phase needs to be treated during desorption,with the upper phase being recycled directly,thus reducing energy consumption.The use of alcohol ether organic solvents can improve the CO_(2)capture performance of absorbents to a certain extent and enhance their regeneration ability,providing a new direction for the subsequent research of non-aqueous absorbents.
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.
基金supported by the National Natural Science Foundation of China(Nos.21971208 and 21771145)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Functional dicyclophanes with various substituents(e.g.,NO_(2),Br,OCH_(3)and OH)were synthesized via one-pot S_(N)2 reaction.Dicyclophanes can form nanospheres via the head-to-tail self-assembly between the cavities and the TPE units to exhibit aggregation-induced emission(AIE)in aqueous solution.These AIE-active nanospheres with cationic feature exhibited selective recognition with fluorescence response for anionic ATP via electrostatic interactions and hydrophobic effects in water.
基金The figures in the article were created by Biorender.
文摘Head and neck cancer(HNC)is malignant,genetically complex and difficult to treat and is the sixth most frequent cancer,with tobacco,alcohol and human papillomavirus being major risk factors.Based on epigenetic data,HNC is remarkably heterogeneous,and treatment remains challenging.There is a lack of significant improvement in survival and quality of life in patients with HNC.Over half of HNC patients experience locoregional recurrence or distal metastasis despite the current multiple traditional therapeutic strategies and immunotherapy.In addition,resistance to chemotherapy,radiotherapy and some targeted therapies is common.Therefore,it is urgent to explore more effective and tolerable targeted therapies to improve the clinical outcomes of HNC patients.Recent targeted therapy studies have focused on identifying promising biomarkers and developing more effective targeted therapies.A well understanding of the pathogenesis of HNC contributes to learning more about its inner association,which provides novel insight into the development of small molecule inhibitors.In this review,we summarized the vital signaling pathways and discussed the current potential therapeutic targets against critical molecules in HNC,as well as presenting preclinical animal models and ongoing or completed clinical studies about targeted therapy,which may contribute to a more favorable prognosis of HNC.Targeted therapy in combination with other therapies and its limitations were also discussed.
基金supported by the National Natural Science Foundation of China(nos.22122108,21971208,and 21771145)the Natural Science Basic Research Plan for Distinguished Young Scholars in Shaanxi Province of China(no.2021JC-37)+1 种基金the Fok Ying Tong Education Foundation(no.171010)the Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates(no.2019B030301003)from South China University of Technology.
文摘The hydrogen-bonded(H-bonded)base pairs,double H-bonded A•T and triple H-bonded G•C in DNA,are important units for storing,encoding,and expressing genetic information.Owing to the interference from water,however,the formation of H-bonded base pairs from short deoxynucleotide fragments such as mono-or di-deoxynucleotide are not easily achieved in aqueous solutions.
基金supported by the National Science Foundation for Excellent Young Scholars(China)(No.32122052)the National Natural Science Foundation Regional Innovation and Development(China)(No.U19A2003).
文摘Ovarian cancer is the tumor with the highest mortality among gynecological malig-nancies.Studies have confirmed that paclitaxel chemoresistance is associated with increased infiltration of tumor-associated macrophages(TAMs)in the microenvironment.Colony-stimu-lating factor 1(CSF-1)receptor(CSF-1R)plays a key role in regulating the number and differ-entiation of macrophages in certain solid tumors.There are few reports on the effects of targeted inhibition of CSF-1R in combination with chemotherapy on ovarian cancer and the tu-mor microenvironment.Here,we explored the antitumor efficacy and possible mechanisms of the CSF-1R inhibitor pexidartinib(PLX3397)when combined with the first-line chemothera-peutic agent paclitaxel in the treatment of ovarian cancer.We found that CSF-1R is highly ex-pressed in ovarian cancer cells and correlates with poor prognosis.Treatment by PLX3397 in combination with paclitaxel significantly inhibited the growth of ovarian cancer both in vitro and in vivo.Blockade of CSF-1R altered the macrophage phenotype and reprogrammed the immunosuppressive cell population in the tumor microenvironment.
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 Natural Science Foundation of Sichuan Province(No.2022NSFSC0774)the National Natural Science Foundation of China(No.82102896).
文摘To the Editor:Current therapeutic strategies against breast cancer are limited by poor prognosis and unwanted side effects,especially in triple-negative breast cancer(TNBC).Ginkgetin(Gk),a natural,non-toxic bioflavonoid extracted from Ginkgo biloba leaves,is a promising therapeutic candidate against breast cancer,[1]but the underlying mechanisms remain obscure.
基金supported by the National Natural Science Foundation of China (22122108, 21971208)the Natural Science Basic Research Plan for Distinguished Young Scholars in Shaanxi Province of China (2021JC-37)the Fok Ying Tong Education Foundation (171010)。
文摘Functional framework materials have been developed for many applications including adsorption, asymmetric catalysis, sensing,drug delivery, optical device, and so on. Here, we report the successive construction of two cucurbit[8]uril-based covalent organic frameworks(COFs) including tetraphenylethene-based COF(COF-1) and phenanthrene-based COF(COF-2) from a two-dimensional(2D) periodic cucurbit[8]uril-based supramolecular organic framework(SOF-1) as the prearranged structure via the intermolecular photocycloaddition of the coumarin units and the intramolecular photocyclization of the tetraphenylethene(TPE) units under ultraviolet(UV) irradiation(365 nm) in water. In this case, oxygen(O_(2)) plays an important role in the photocyclization of the TPE units into the phenanthrene units in the transform process from SOF-1 or COF-1 to COF-2. As the TPE units further form phenanthrenes after UV-irradiation, COF-2 exhibits aggregation-caused quenching effect and weak green emission, while COF-1 displays a strong yellow emission due to the aggregation-induced emission. Besides, the adaptive chirality of cationic COF-1 as a biomolecular sensor can be efficiently induced by chiral anionic biomolecules including adenosine-5′-triphosphate(ATP) and adenosine-5′-diphosphate(ADP) to exhibit sensitive negative circular dichroism responses in water. This supramolecular approach to construct COF from SOF via photochemical reactions may open a new opportunity for the construction and application of the water-soluble COFs with well structural controllability, unique photophysical properties,and favorable biocompatibility.
