Nor-seco-cucurbit[10]uril(ns-CB[10])is a kinetic product with unique structure.The single bridged methylene in its structure makes the molecular cavity of ns-CB[10]more deformable when compared to ordinary cucurbit[n]...Nor-seco-cucurbit[10]uril(ns-CB[10])is a kinetic product with unique structure.The single bridged methylene in its structure makes the molecular cavity of ns-CB[10]more deformable when compared to ordinary cucurbit[n]uril,reducing its structural stability.Repeated experiments showed that ns-CB[10]gradually cracks in an acidic solution and changes the specificity of cucurbit[5]uril(CB[5])and cucurbit[8]uril(CB[8])under more robust acidic solutions and when heated.A series of experiments were designed to study the transformation behavior of ns-CB[10].It was found that the concentration of ns-CB[10]was correlated with the content distribution of CB[5]and CB[8].This study explores the influencing factors and mechanisms of the transformation of ns-CB[10]to CB[5]and CB[8].The results are of great significance for the application of ns-CB[10],understanding the formation mechanism of cucurbit[n]urils.Furthermore,it provides a new pathway for synthesizing new cucurbit[n]urils.展开更多
The ongoing development of small molecule drugs underscores the urgent need for novel excipients to formulate poorly soluble drug candidates.Cucurbit[7]uril(CB[7])possesses high binding affinities for a variety of mol...The ongoing development of small molecule drugs underscores the urgent need for novel excipients to formulate poorly soluble drug candidates.Cucurbit[7]uril(CB[7])possesses high binding affinities for a variety of molecular vips.However,its moderate water solubility limits broader application.Here we report the synthesis of three CB[7]derivatives M1-M3 by modifying an average of 4.2,5.5,and 5.9 sulfonatopropoxy groups onto their"equator"carbons.Compared to CB[7],their water-solubility increased by at least 26.6-,23.6-,and 19.2-fold,respectively,while the maximum tolerated doses(MTD)of M1 and M2 improved by 2.5-and 2.3-fold.Phase solubility diagram studies demonstrate that M1 and M2 significantly enhance the water-solubility of eighteen poorly soluble drugs.In vivo experiments in rat complete Freund's arthritis reveal that M1 not only improves the anti-inflammatory efficacy of indomethacin by up to 52%,but also substantially reduces its side effect of gastric ulcer.展开更多
The cross-photodimerization often comes with the formation of undesired and competitive homophotodimer as side products.Herein,we report a series of highly selective[4+4]cross-photodimerization between anthracene and ...The cross-photodimerization often comes with the formation of undesired and competitive homophotodimer as side products.Herein,we report a series of highly selective[4+4]cross-photodimerization between anthracene and 4a-azoniaanthracene derivatives within a cucurbit[10]uril(CB[10])host in water.Heteroternary inclusion complexes were formed through encapsulation of donor(D1-D2,anthracene derivative)and acceptor(A1-A3,4a-azoniaanthracene derivatives)pairs in CB[10].In the presence of CB[10](1.0 equiv.),the[4+4]cross-photodimerization between D1 and A1/A2/A3 efficiently gave a single racemic cross-photodimer.Furthermore,the cross-photodimerization between 9-substituted anthracene D2 and A1/A3 was catalyzed by CB[10](0.1 equiv.)to quantitatively yield a cross-photodimer with high regioselectivity.Efficient formation of selective cross-photodimers could be attributed to the exclusive encapsulation of D-A hetero-vip pairs in CB[10]and the confinement effect of the CB[10]host cavity.Our study further proves host–vip complexation as a powerful strategy for cross-cycloaddition reactions with high efficiency.展开更多
Selective separation of amino acids and proteins is crucial in various areas of research,including proteomics,protein structure and function studies,protein purification and drug development,and biosensing and biodete...Selective separation of amino acids and proteins is crucial in various areas of research,including proteomics,protein structure and function studies,protein purification and drug development,and biosensing and biodetection.A nanocomposite film is formed by combining layer-by-layer self-assembled gold nanospheres(Au NPs)driven by cucurbit[7]uril(CB[7])and polymethyl methacrylate(PMMA)film.Due to the host-vip interactions,the selective transmission of l-tryptophan in the nanocomposite film is confirmed by the current-voltage measurements using a picoammeter.Furthermore,by adjusting the particle size of Au NPs to increase channel size,lysozyme containing multiple tryptophan residues can selectively pass through the nanocomposite film,indicating the high versatility and adaptability of the nanocomposite film.This study will provide a new direction for the selective separation of amino acids and proteins.展开更多
Pyridine(Py) and 3-methylpyridine(3-MP) are crucial intermediates in chemical industrial processes.Here,we provide a simple and energy-efficient approach for the isolation of Py and 3-MP by employing crystalline cucur...Pyridine(Py) and 3-methylpyridine(3-MP) are crucial intermediates in chemical industrial processes.Here,we provide a simple and energy-efficient approach for the isolation of Py and 3-MP by employing crystalline cucurbit[6]uril(Q[6]).The crystal exhibit high selectivity for Py from the mixture of Py and 3-MP in both vapor and liquid phases,with separation purities close to 100%.The selectivity is attributed to the varying stability of the host-vip complexes after the absorption of Py or 3-MP,as revealed by the single-crystal structure analysis.ITC experimental results and DFT calculations indicate that,compared to3-MP,Q[6] has a higher binding strength and lower binding energy with Py.In addition,pyridine can be removed from the Q[6] cavity through vacuum heating or organic solvent immersion,enabling Q[6]reuse via reversible vip loading.This method offers a promising approach for high-purity Py and 3-MP separation with significant economic and environmental benefits.展开更多
Host-vip recognition-based macrocycle in macrocycle to form"Russian doll"assemblies remains an interesting topic in supramolecular chemistry.Herein,a macrocycle-in-macrocycle assembly was studied using cuc...Host-vip recognition-based macrocycle in macrocycle to form"Russian doll"assemblies remains an interesting topic in supramolecular chemistry.Herein,a macrocycle-in-macrocycle assembly was studied using cucurbit[10]uril(Q[10])and the smallest cucurbituril-like macrocycle(TD[4]).X-ray crystal structure analysis revealed that TD[4]was encapsulated in the cavity of Q[10]to form a 1:1 complex.Importantly,competitive vip studies suggested that TD[4]had the highest binding constant with the Q[10]host among the vips used,including Q[5],Me_(8)TD[4],and amantadine molecules in water.Our results provided a new cucurbituril-based Russian-doll structure containing both the largest and smallest cavities of the cucurbiturils,which expanded the family of molecular Russian dolls.展开更多
New fabrication method of nanostructures is of great importance for the applications of nanoscience and nanotechnology.This review summarizes cucurbit[n]uril(CB[n])-based nanostructure fabrication and modification app...New fabrication method of nanostructures is of great importance for the applications of nanoscience and nanotechnology.This review summarizes cucurbit[n]uril(CB[n])-based nanostructure fabrication and modification approaches.These strategies include the use of CB[n]s as building blocks and supramolecular crosslinkers to fabricate nanostructures,to surface modify nanostructures,and as gatekeepers to control the release of encapsulated cargo.These nanostructures are used for drug delivery,bioimaging,chemical sensing,catalysis and other applications.CB[n]s often play a vital role in the fabrication of these nanos-tructures,and the realization of the applications.展开更多
Thispaper has investigated the coordination and supramolecular assemblies of alkali metal ions,cucurbit[5]uril(Q[5]),and[CdCl_(4)]^(2-)to confirm whether[CdCl_(4)]^(2-)can produce the“honeycomb effect”,induce coordi...Thispaper has investigated the coordination and supramolecular assemblies of alkali metal ions,cucurbit[5]uril(Q[5]),and[CdCl_(4)]^(2-)to confirm whether[CdCl_(4)]^(2-)can produce the“honeycomb effect”,induce coordination of alkali metal ions to Q[5],and form linear coordination polymers.In this work,the effect of alkali metal ions on the construction of Q[5]-Cd^(2+)ion system under acidic conditions was investigated.Five complexes were successfully obtained by solvent evaporation method.Among the five crystal structures obtained,it can be observed that the presence of[CdCl_(4)]^(2-)did not result in the complexation of alkali metal ions by the Q[5]molecule.Instead,a bowl-like Cd^(2+)@Q[5]complex was formed.Indeed,[CdCl_(4)]^(2-)did not produce the honeycomb effect but led to the formation of Q[5]-based honeycomb frameworks with hexagonal cellsoccupied by[CdCl_(4)]^(2-).The experimental results show that cadmium ion showed stronger ability to coordinate to Q[5]in HCl solution.展开更多
A linear supramolecular polymer with controllable features based on twisted cucurbit[14]uril(tQ[14])and cucurbit[8]uril(Q[8])was firstly fabricated via an effective self-sorting strategy.Herein we designed a monomer,1...A linear supramolecular polymer with controllable features based on twisted cucurbit[14]uril(tQ[14])and cucurbit[8]uril(Q[8])was firstly fabricated via an effective self-sorting strategy.Herein we designed a monomer,1–butyl–1?-(naphthalen-2-ylmethyl)-4,4?-bipyridinium bromide(BNB),that contains bipyridyl,aliphatic butyl and aromatic naphthyl groups,simultaneously.Two host molecules,tQ[14]and Q[8]were employed to develop an effective strategy for constructing a linear supramolecular polymer with con-trollable features.The alkyl groups on both sides of BNB could insert into the two cavities of tQ[14],the naphthyl part of BNB viaπ-πstacking in Q[8]cavity,serving as the driving force for supramolecular polymerization.Through self-sorting of the monomer,tQ[14]and Q[8],led to the formation of the linear supramolecular polymer.Depolymerization could be achieved by addition of adamantane hydrochloride(AH)which driven two BNB vip molecules out of the Q[8]cavity.This self-sorting strategy has great potential,not only for designing supramolecular polymer materials with different controllable structures through introduction of multiple functional groups,but also for broadening the application of twisted cucurbit[14]uril in supramolecular chemistry.展开更多
Sym-bis（benzimidazole）-2,2＇-ethylene cations act as a new axle template for threading cucurbit[6]uril derivatives on,forming[2]pseudorotaxane and[3]pseudorotaxane.These new complexes have been studied using 1 H NMR...Sym-bis（benzimidazole）-2,2＇-ethylene cations act as a new axle template for threading cucurbit[6]uril derivatives on,forming[2]pseudorotaxane and[3]pseudorotaxane.These new complexes have been studied using 1 H NMR,UV-vis absorption spectroscopy and X-ray analysis.Changes in the 1 H NMR spectra indicate that the two types of pseudorotaxane can be formed by varying the host concentration. UV-vis absorption titration experiments at different pH values demonstrate that interesting pK_a shifts of the bis-benzimidazole derivatives can be induced by the host-vip complexation.The associated constants were calculated to be 2.81×10^4 L/mol and 9.06×10^6 L/mol for the[2]pseudorotaxanes and ｜3]pseudorotaxanes,respectively.Furthermore,X-ray diffraction studies of the solid state structures provide unequivocal proof of the host concentration dependent pseudorotaxane,which is strongly in line with the evidences in solution.展开更多
The determination method of L-phenylalartine （LPA） by fluorescence quenching was developed. The assay was based on the combination of the cucurbit[7]uril （CB [7]） with palmatine hydrochloride （PAL） reaction. In ...The determination method of L-phenylalartine （LPA） by fluorescence quenching was developed. The assay was based on the combination of the cucurbit[7]uril （CB [7]） with palmatine hydrochloride （PAL） reaction. In the presence of CB [7], the fluorescence of PAL was quenched by LPA which can be employed to detect LPA. Under the optimal conditions, a linear range 3.63 ×10^-8- 9.68 ×10^-6 mol/L and a detection limit 1.27 ×10^-8 mol/L of LPA were obtained. The relative standard deviation （R.S.D） was 1.8% obtained from a series of 11 standards each containing 6.05 ×10^-6 mol/L of LPA. This paper also discusses the mechanism of fluorescence indicator probe.展开更多
Cucurbit[n]urils （CB[n]s, n = 5-8,10,13-15） have been proven to be an interesting macrocyclic family with their distinctive molecular recognition properties and fascinating applications in fields such as catalysis, ...Cucurbit[n]urils （CB[n]s, n = 5-8,10,13-15） have been proven to be an interesting macrocyclic family with their distinctive molecular recognition properties and fascinating applications in fields such as catalysis, supramolecular materials, drug delivery and biological systems. With the biggest cavity in the CB[n]s family. CB[ 10] shows its unique molecular recognition properties that are rather distinctive from other CB [n]is. In this review, we summarize the progresses in CB[10]-based chemistry since CB[10] was first reported as CB[10]-CB[5] complex in 2001. Purification, molecular recognition and supramolecular assembly of CB[ 10] will be described and an outlook will be given for further exploration of CB[10]-based chemistry.展开更多
A new cucurbit[6]uril bridsed binuclear complex {[Gd（H2O）6]2[Q6（H2O）]}C16·4H2O, where Q6 represents cucurbit[6]uril, has been synthesized and characterized by X-ray diffraction. The crystal structure shows th...A new cucurbit[6]uril bridsed binuclear complex {[Gd（H2O）6]2[Q6（H2O）]}C16·4H2O, where Q6 represents cucurbit[6]uril, has been synthesized and characterized by X-ray diffraction. The crystal structure shows that the complex has an extended cucurbit[6]uril-bridged structure consisting of two gadolinium（Ⅲ） ions, in which each gadolinium（Ⅲ） ion is coordinated with two neighboring carbonylic oxygen atoms of Q6 and six oxygen atoms of water molecules that leans toward one side of the portal. One disordered vip water molecule resides in the Q6 molecule cavity and occupies two different positions. Hydrogen bonds assemble the complcx to threedimensional supramolecular structure.展开更多
A supramolecular dimer of doxorubicin(DOX)was constructed via ternary host-vip interactions between cucurbit[8]uril(CB[8])and tryptophan modified DOX(DOX-Trp,connected with an acid-labile bond)and we demonstrate for...A supramolecular dimer of doxorubicin(DOX)was constructed via ternary host-vip interactions between cucurbit[8]uril(CB[8])and tryptophan modified DOX(DOX-Trp,connected with an acid-labile bond)and we demonstrate for the first time that a supramolecular dimer of DOX can be formed upon homo-dimerization by CB[8],which may act as a stimuli pH-responsive,supramolecular DOX dimer prodrug system.This supramolecular DOX dimer transported DOX efficiently and selectively to cancer cells,thereby exhibiting significantly minimized cytotoxicity against noncancerous cells while maintaining effective cytotoxicity against cancer cells.Under this strategy,many other anticancer drugs could be chemically modified and loaded as a dimeric"ammunition"into CB[8]as supramolecular dimer prodrug systems(or a"jet fighter")for improved cancer therapy.展开更多
A rigid supramolecular polymer was constructed in aqueous solution via cucurbit[8]uril （CB[8]） host recognition with a rigid monomer containing an azobenzene unit and two 4,4＇-bipyridin-l-ium （BP） moieties in the...A rigid supramolecular polymer was constructed in aqueous solution via cucurbit[8]uril （CB[8]） host recognition with a rigid monomer containing an azobenzene unit and two 4,4＇-bipyridin-l-ium （BP） moieties in the two ends, which also exhibited photo-responsiveness owing to the photoinduced trans- cis ~somerization of azobenzene group.展开更多
Thermo-gelation polymers have attracted increasing attention over decades. However, rare facile tuning method of sol-gel transition temperature restricted the wider application. Preceding study indicated that supramol...Thermo-gelation polymers have attracted increasing attention over decades. However, rare facile tuning method of sol-gel transition temperature restricted the wider application. Preceding study indicated that supramolecular interactions demonstrated a powerful means to control the structure and property of polymeric materials. Here we designed an N-isopropylacrylamide （NIPAM） based thermo-sensitive copolymer with naphthyl （Np） on its side chain. Positive-charged side-chain ternary complex was formed with cucurbit[8]uril （CB[8]） and methylviologen （MV2＋） via CB[8]-enhanced intermolecular charge-transfer （CT） interaction. Introducing the ternary complex CB[8]/MV2＋/Np on side-chain altered microstructure of macromolecular chains and led to a strong tendency for thermo gelation. Altering content of CB[8] and MV2＋ changed content of the positive-charged side-chain ternary complex and varied gelation temperature. Therefore, introducing supramolecular interaction endowed the hydrogel with tunable gelation property.展开更多
In this study, cucurbit[8]uril （CB[8]） was utilized as a kind of new adsorbent to remove Pb^2＋ ions from aqueous solution. With the solution pH increased from 2 to 6, the removal efficiency of adsorption increased ...In this study, cucurbit[8]uril （CB[8]） was utilized as a kind of new adsorbent to remove Pb^2＋ ions from aqueous solution. With the solution pH increased from 2 to 6, the removal efficiency of adsorption increased from 55.6% to 74.5%correspondingly. The uptake of Pb^2＋ increased rapidly in the initial 30 min, and then the adsorption rate became slower. The Pseudo-second order model could be used to interpret the adsorption kinetics satisfactorily; and the rate determining step in Pb^2＋ adsorption onto CB[8] was the external mass transfer step. Equilibrium isotherm study reveals that the Langmuir model gave a better fitting result than Freundlich model. The maximum adsorption capacity calculated by the Langmuir model was 152.67 mg/g for 298 K, 149.70 mg/g for 313 K and 136.42 mg/g for 323 K, respectively. The adsorption is a spontaneous process of exothermic nature. The effect of the adsorbent dosage and the influences of solution pH and co-existing cations were also investigated. The CB[8] was synthesized and characterized by 1H NMR, IR, ESI-MS spectra, SEM-EDAX, Zeta-potential and BET-analysis. The adsorption mechanism was due to the coordination between CB[8] molecule and Pb^2＋ ions.展开更多
A novel supramolecular graft copolymer （SGP） composed of viologen-containing copolymer （P（DMA-co- diEV）） as the main chain and Np ended PNIPAM （Np-PNIPAm） as the grafts is prepared （DMA： N,N- dimethylacryami...A novel supramolecular graft copolymer （SGP） composed of viologen-containing copolymer （P（DMA-co- diEV）） as the main chain and Np ended PNIPAM （Np-PNIPAm） as the grafts is prepared （DMA： N,N- dimethylacryamide, diEV： ethylviologen dimer, Np： naphthalene, PNIPAM： poly（N-isopropylacrylamide））. The grafting is based on the triple complexation among a host of cucurbit[8]uril （CB[8]） and two vips of diEV and Np, which is characterized by UV-vis spectra and ITC. Temperature sensitive property of PNIPAm moiety allows SGP to self-assemble into non-covalently connected micelle （NCCM） at high temperature. The micelles are sensitive to reducing agents, for example Na2S203, which breaks the current inclusion complex pair and induces aggregation.展开更多
We report herein a new fluorescent probe for the selective recognition and determination of dodine among 20 different pesticides.This fluorescent probe was assembled through host-vip complexation between cucurbit[10...We report herein a new fluorescent probe for the selective recognition and determination of dodine among 20 different pesticides.This fluorescent probe was assembled through host-vip complexation between cucurbit[10]uril(Q[10]) and aminopropyl-1-pyrenebutanamide(PBA) and is designated as PBA@Q[10].Addition of dodine to PBA@Q[10] results in a dramatic enhancement of fluorescence intensity at 390 nm,accompanied by fluorescence quenching at 488 nm.On this basis,the detection limit is 6.78 × 10^(-7) mol/L.The response mechanism is a competitive interaction:dodine occupies the cavity of Q[10] and forces PBA to leave.展开更多
The wide-spreading SARS-CoV-2 virus has put the world into boiling water for more than a year,however pharmacological therapies to act effectively against coronavirus disease 2019(COVID-19)remain elusive.Chloroquine(C...The wide-spreading SARS-CoV-2 virus has put the world into boiling water for more than a year,however pharmacological therapies to act effectively against coronavirus disease 2019(COVID-19)remain elusive.Chloroquine(CQ),an antimalarial drug,was found to exhibit promising antiviral activity in vitro and in vivo at a high dosage,thus CQ was approved by the FDA for the emergency use authorization(EUA)in the fight against COVID-19 in the US,but later was revoked the EUA status due to the severe clinical toxicity.Herein,we show that supramolecular formulation of CQ by a macrocyclic host,curcurbit[7]uril(CB[7]),reduced its non-specific toxicity and improved its antiviral activity against coronavirus,working in synergy with CB[7].CB[7]was found to form 1:1 host-vip complexes with CQ,with a binding constant of$104 L/mol.The CQ-CB[7]formulation decreased the cytotoxicity of CQ against Vero E6 and L-02 cell lines.In particular,the cytotoxicity of CQ(60 mmol/L)against both Vero E6 cell line and L-02 cell lines was completely inhibited in the presence of 300 mmol/L and 600 mmol/L CB[7],respectively.Furthermore,the CB[7]alone showed astonishing antiviral activity in SARS-CoV-2 infected Vero E6 cells and mouse hepatitis virus strain A59(MHV-A59)infected N2 A cells,and synergistically improved the antiviral activity of CQ-CB[7],suggesting that CB[7]-based CQ formulation has a great potential as a safe and effective antiviral agent against SARS-CoV-2 and other coronavirus.展开更多
基金financial support of National Natural Science Foundation of China(No.22161010)。
文摘Nor-seco-cucurbit[10]uril(ns-CB[10])is a kinetic product with unique structure.The single bridged methylene in its structure makes the molecular cavity of ns-CB[10]more deformable when compared to ordinary cucurbit[n]uril,reducing its structural stability.Repeated experiments showed that ns-CB[10]gradually cracks in an acidic solution and changes the specificity of cucurbit[5]uril(CB[5])and cucurbit[8]uril(CB[8])under more robust acidic solutions and when heated.A series of experiments were designed to study the transformation behavior of ns-CB[10].It was found that the concentration of ns-CB[10]was correlated with the content distribution of CB[5]and CB[8].This study explores the influencing factors and mechanisms of the transformation of ns-CB[10]to CB[5]and CB[8].The results are of great significance for the application of ns-CB[10],understanding the formation mechanism of cucurbit[n]urils.Furthermore,it provides a new pathway for synthesizing new cucurbit[n]urils.
基金National Natural Science Foundation of China(Nos.21921003 and 22201293)the National Key R&D Program of China(No.2023YFC3503400)for financial support。
文摘The ongoing development of small molecule drugs underscores the urgent need for novel excipients to formulate poorly soluble drug candidates.Cucurbit[7]uril(CB[7])possesses high binding affinities for a variety of molecular vips.However,its moderate water solubility limits broader application.Here we report the synthesis of three CB[7]derivatives M1-M3 by modifying an average of 4.2,5.5,and 5.9 sulfonatopropoxy groups onto their"equator"carbons.Compared to CB[7],their water-solubility increased by at least 26.6-,23.6-,and 19.2-fold,respectively,while the maximum tolerated doses(MTD)of M1 and M2 improved by 2.5-and 2.3-fold.Phase solubility diagram studies demonstrate that M1 and M2 significantly enhance the water-solubility of eighteen poorly soluble drugs.In vivo experiments in rat complete Freund's arthritis reveal that M1 not only improves the anti-inflammatory efficacy of indomethacin by up to 52%,but also substantially reduces its side effect of gastric ulcer.
基金financially supported by the National Natural Science Foundation of China(No.21871216)。
文摘The cross-photodimerization often comes with the formation of undesired and competitive homophotodimer as side products.Herein,we report a series of highly selective[4+4]cross-photodimerization between anthracene and 4a-azoniaanthracene derivatives within a cucurbit[10]uril(CB[10])host in water.Heteroternary inclusion complexes were formed through encapsulation of donor(D1-D2,anthracene derivative)and acceptor(A1-A3,4a-azoniaanthracene derivatives)pairs in CB[10].In the presence of CB[10](1.0 equiv.),the[4+4]cross-photodimerization between D1 and A1/A2/A3 efficiently gave a single racemic cross-photodimer.Furthermore,the cross-photodimerization between 9-substituted anthracene D2 and A1/A3 was catalyzed by CB[10](0.1 equiv.)to quantitatively yield a cross-photodimer with high regioselectivity.Efficient formation of selective cross-photodimers could be attributed to the exclusive encapsulation of D-A hetero-vip pairs in CB[10]and the confinement effect of the CB[10]host cavity.Our study further proves host–vip complexation as a powerful strategy for cross-cycloaddition reactions with high efficiency.
基金financially supported by National Natural Science Foundation of China(Nos.22371086,22071074,21772055)the National Key Research and Development Program(No.2021YFA0716702)+3 种基金the 111 Project(No.B17019)the China Postdoctoral Science Foundation(No.2020 M672388)Self-determined research funds of CCNU from the colleges’basic research and operation of MOE,National Natural Science Foundation of China(No.22006055)the State Key Laboratory of Environmental Chemistry and Ecotoxicology,RCEES,CAS(No.KF2017-4)。
文摘Selective separation of amino acids and proteins is crucial in various areas of research,including proteomics,protein structure and function studies,protein purification and drug development,and biosensing and biodetection.A nanocomposite film is formed by combining layer-by-layer self-assembled gold nanospheres(Au NPs)driven by cucurbit[7]uril(CB[7])and polymethyl methacrylate(PMMA)film.Due to the host-vip interactions,the selective transmission of l-tryptophan in the nanocomposite film is confirmed by the current-voltage measurements using a picoammeter.Furthermore,by adjusting the particle size of Au NPs to increase channel size,lysozyme containing multiple tryptophan residues can selectively pass through the nanocomposite film,indicating the high versatility and adaptability of the nanocomposite film.This study will provide a new direction for the selective separation of amino acids and proteins.
基金supported by the Guizhou Provincial Basic Research Program(Natural Science) Youth Guidance(Nos.[2024]110,[2024]378)Science and Technology Innovation Team of Natural Science Foundation of Guizhou Province(No.CXTD[2023]005)+3 种基金Science and Technology Innovation Team of Higher Education Department of Guizhou Province(No.QJJ[2023]053)Natural Science Special of Guizhou University(No.202137)Guizhou Provincial Key Laboratory Platform Project(No.ZSYS[2025]008)PhD Foundation of Guizhou University(No.[2021]83)。
文摘Pyridine(Py) and 3-methylpyridine(3-MP) are crucial intermediates in chemical industrial processes.Here,we provide a simple and energy-efficient approach for the isolation of Py and 3-MP by employing crystalline cucurbit[6]uril(Q[6]).The crystal exhibit high selectivity for Py from the mixture of Py and 3-MP in both vapor and liquid phases,with separation purities close to 100%.The selectivity is attributed to the varying stability of the host-vip complexes after the absorption of Py or 3-MP,as revealed by the single-crystal structure analysis.ITC experimental results and DFT calculations indicate that,compared to3-MP,Q[6] has a higher binding strength and lower binding energy with Py.In addition,pyridine can be removed from the Q[6] cavity through vacuum heating or organic solvent immersion,enabling Q[6]reuse via reversible vip loading.This method offers a promising approach for high-purity Py and 3-MP separation with significant economic and environmental benefits.
基金supported by the National Natural Science Foundation of China(No.2271090)。
文摘Host-vip recognition-based macrocycle in macrocycle to form"Russian doll"assemblies remains an interesting topic in supramolecular chemistry.Herein,a macrocycle-in-macrocycle assembly was studied using cucurbit[10]uril(Q[10])and the smallest cucurbituril-like macrocycle(TD[4]).X-ray crystal structure analysis revealed that TD[4]was encapsulated in the cavity of Q[10]to form a 1:1 complex.Importantly,competitive vip studies suggested that TD[4]had the highest binding constant with the Q[10]host among the vips used,including Q[5],Me_(8)TD[4],and amantadine molecules in water.Our results provided a new cucurbituril-based Russian-doll structure containing both the largest and smallest cavities of the cucurbiturils,which expanded the family of molecular Russian dolls.
基金National Natural Science Foundation of China(No.21921003)for financial support.
文摘New fabrication method of nanostructures is of great importance for the applications of nanoscience and nanotechnology.This review summarizes cucurbit[n]uril(CB[n])-based nanostructure fabrication and modification approaches.These strategies include the use of CB[n]s as building blocks and supramolecular crosslinkers to fabricate nanostructures,to surface modify nanostructures,and as gatekeepers to control the release of encapsulated cargo.These nanostructures are used for drug delivery,bioimaging,chemical sensing,catalysis and other applications.CB[n]s often play a vital role in the fabrication of these nanos-tructures,and the realization of the applications.
文摘Thispaper has investigated the coordination and supramolecular assemblies of alkali metal ions,cucurbit[5]uril(Q[5]),and[CdCl_(4)]^(2-)to confirm whether[CdCl_(4)]^(2-)can produce the“honeycomb effect”,induce coordination of alkali metal ions to Q[5],and form linear coordination polymers.In this work,the effect of alkali metal ions on the construction of Q[5]-Cd^(2+)ion system under acidic conditions was investigated.Five complexes were successfully obtained by solvent evaporation method.Among the five crystal structures obtained,it can be observed that the presence of[CdCl_(4)]^(2-)did not result in the complexation of alkali metal ions by the Q[5]molecule.Instead,a bowl-like Cd^(2+)@Q[5]complex was formed.Indeed,[CdCl_(4)]^(2-)did not produce the honeycomb effect but led to the formation of Q[5]-based honeycomb frameworks with hexagonal cellsoccupied by[CdCl_(4)]^(2-).The experimental results show that cadmium ion showed stronger ability to coordinate to Q[5]in HCl solution.
基金supported by the National Natural Science Foundation of China (Nos. 21861011, 21871064)the Innovation Program for High-level Talents of Guizhou Province (No. 2016–5657)the Graduate scientific research Fund of Guizhou Province (No. YJSCXJH-2019–011)
文摘A linear supramolecular polymer with controllable features based on twisted cucurbit[14]uril(tQ[14])and cucurbit[8]uril(Q[8])was firstly fabricated via an effective self-sorting strategy.Herein we designed a monomer,1–butyl–1?-(naphthalen-2-ylmethyl)-4,4?-bipyridinium bromide(BNB),that contains bipyridyl,aliphatic butyl and aromatic naphthyl groups,simultaneously.Two host molecules,tQ[14]and Q[8]were employed to develop an effective strategy for constructing a linear supramolecular polymer with con-trollable features.The alkyl groups on both sides of BNB could insert into the two cavities of tQ[14],the naphthyl part of BNB viaπ-πstacking in Q[8]cavity,serving as the driving force for supramolecular polymerization.Through self-sorting of the monomer,tQ[14]and Q[8],led to the formation of the linear supramolecular polymer.Depolymerization could be achieved by addition of adamantane hydrochloride(AH)which driven two BNB vip molecules out of the Q[8]cavity.This self-sorting strategy has great potential,not only for designing supramolecular polymer materials with different controllable structures through introduction of multiple functional groups,but also for broadening the application of twisted cucurbit[14]uril in supramolecular chemistry.
基金supported by the National Natural Science Foundation of China(No,21272045)the Natural Science Foundation of Guizhou Province and Guizhou Universitythe "Chun-Hui" Funds of the Chinese Ministry of Education are gratefully acknowledged
文摘Sym-bis（benzimidazole）-2,2＇-ethylene cations act as a new axle template for threading cucurbit[6]uril derivatives on,forming[2]pseudorotaxane and[3]pseudorotaxane.These new complexes have been studied using 1 H NMR,UV-vis absorption spectroscopy and X-ray analysis.Changes in the 1 H NMR spectra indicate that the two types of pseudorotaxane can be formed by varying the host concentration. UV-vis absorption titration experiments at different pH values demonstrate that interesting pK_a shifts of the bis-benzimidazole derivatives can be induced by the host-vip complexation.The associated constants were calculated to be 2.81×10^4 L/mol and 9.06×10^6 L/mol for the[2]pseudorotaxanes and ｜3]pseudorotaxanes,respectively.Furthermore,X-ray diffraction studies of the solid state structures provide unequivocal proof of the host concentration dependent pseudorotaxane,which is strongly in line with the evidences in solution.
基金supported by the Research Fund for the Doctoral Program of Higher Education of China(No. 20091404110001)the foundation of Shanxi Normal University(No.ZR1007)
文摘The determination method of L-phenylalartine （LPA） by fluorescence quenching was developed. The assay was based on the combination of the cucurbit[7]uril （CB [7]） with palmatine hydrochloride （PAL） reaction. In the presence of CB [7], the fluorescence of PAL was quenched by LPA which can be employed to detect LPA. Under the optimal conditions, a linear range 3.63 ×10^-8- 9.68 ×10^-6 mol/L and a detection limit 1.27 ×10^-8 mol/L of LPA were obtained. The relative standard deviation （R.S.D） was 1.8% obtained from a series of 11 standards each containing 6.05 ×10^-6 mol/L of LPA. This paper also discusses the mechanism of fluorescence indicator probe.
基金financially supported by the National Natural Science Foundation of China (Nos. 21472143, 21604066 and 21372183)Thousand Youth Talents Program of China (No. D1118031)Program for Innovative Teams of Outstanding Young and Middle-aged Researchers in the Higher Education Institutions of Hubei Province (No. T201602)
文摘Cucurbit[n]urils （CB[n]s, n = 5-8,10,13-15） have been proven to be an interesting macrocyclic family with their distinctive molecular recognition properties and fascinating applications in fields such as catalysis, supramolecular materials, drug delivery and biological systems. With the biggest cavity in the CB[n]s family. CB[ 10] shows its unique molecular recognition properties that are rather distinctive from other CB [n]is. In this review, we summarize the progresses in CB[10]-based chemistry since CB[10] was first reported as CB[10]-CB[5] complex in 2001. Purification, molecular recognition and supramolecular assembly of CB[ 10] will be described and an outlook will be given for further exploration of CB[10]-based chemistry.
基金supported by the National Natural Science Foundation of China(No.20471056)
文摘A new cucurbit[6]uril bridsed binuclear complex {[Gd（H2O）6]2[Q6（H2O）]}C16·4H2O, where Q6 represents cucurbit[6]uril, has been synthesized and characterized by X-ray diffraction. The crystal structure shows that the complex has an extended cucurbit[6]uril-bridged structure consisting of two gadolinium（Ⅲ） ions, in which each gadolinium（Ⅲ） ion is coordinated with two neighboring carbonylic oxygen atoms of Q6 and six oxygen atoms of water molecules that leans toward one side of the portal. One disordered vip water molecule resides in the Q6 molecule cavity and occupies two different positions. Hydrogen bonds assemble the complcx to threedimensional supramolecular structure.
基金supported by the Science and Technology Development Fund,Macao SAR(No.030/2017/A1)University of Macao(No.MYRG2016-00008-ICMS-QRCM)the National Natural Science Foundation of China(No.21871301)。
文摘A supramolecular dimer of doxorubicin(DOX)was constructed via ternary host-vip interactions between cucurbit[8]uril(CB[8])and tryptophan modified DOX(DOX-Trp,connected with an acid-labile bond)and we demonstrate for the first time that a supramolecular dimer of DOX can be formed upon homo-dimerization by CB[8],which may act as a stimuli pH-responsive,supramolecular DOX dimer prodrug system.This supramolecular DOX dimer transported DOX efficiently and selectively to cancer cells,thereby exhibiting significantly minimized cytotoxicity against noncancerous cells while maintaining effective cytotoxicity against cancer cells.Under this strategy,many other anticancer drugs could be chemically modified and loaded as a dimeric"ammunition"into CB[8]as supramolecular dimer prodrug systems(or a"jet fighter")for improved cancer therapy.
基金financially supported by NNSFC (Nos. 21190033, 21272072, 21476075 and 21372076)the National Basic Research 973 Program (No. 2011CB808400)+1 种基金the Shanghai Pujiang Program (No. 13PJD011)the Fundamental Research Funds for the Central Universities
文摘A rigid supramolecular polymer was constructed in aqueous solution via cucurbit[8]uril （CB[8]） host recognition with a rigid monomer containing an azobenzene unit and two 4,4＇-bipyridin-l-ium （BP） moieties in the two ends, which also exhibited photo-responsiveness owing to the photoinduced trans- cis ~somerization of azobenzene group.
基金financially supported by the National Natural Science Foundation of China(No.21374055)
文摘Thermo-gelation polymers have attracted increasing attention over decades. However, rare facile tuning method of sol-gel transition temperature restricted the wider application. Preceding study indicated that supramolecular interactions demonstrated a powerful means to control the structure and property of polymeric materials. Here we designed an N-isopropylacrylamide （NIPAM） based thermo-sensitive copolymer with naphthyl （Np） on its side chain. Positive-charged side-chain ternary complex was formed with cucurbit[8]uril （CB[8]） and methylviologen （MV2＋） via CB[8]-enhanced intermolecular charge-transfer （CT） interaction. Introducing the ternary complex CB[8]/MV2＋/Np on side-chain altered microstructure of macromolecular chains and led to a strong tendency for thermo gelation. Altering content of CB[8] and MV2＋ changed content of the positive-charged side-chain ternary complex and varied gelation temperature. Therefore, introducing supramolecular interaction endowed the hydrogel with tunable gelation property.
基金support provided by the National Nature Science Foundation of China (Nos. 51208179, 21202037)the Doctor Fund of Henan University of Technology (No. 2013BS066)
文摘In this study, cucurbit[8]uril （CB[8]） was utilized as a kind of new adsorbent to remove Pb^2＋ ions from aqueous solution. With the solution pH increased from 2 to 6, the removal efficiency of adsorption increased from 55.6% to 74.5%correspondingly. The uptake of Pb^2＋ increased rapidly in the initial 30 min, and then the adsorption rate became slower. The Pseudo-second order model could be used to interpret the adsorption kinetics satisfactorily; and the rate determining step in Pb^2＋ adsorption onto CB[8] was the external mass transfer step. Equilibrium isotherm study reveals that the Langmuir model gave a better fitting result than Freundlich model. The maximum adsorption capacity calculated by the Langmuir model was 152.67 mg/g for 298 K, 149.70 mg/g for 313 K and 136.42 mg/g for 323 K, respectively. The adsorption is a spontaneous process of exothermic nature. The effect of the adsorbent dosage and the influences of solution pH and co-existing cations were also investigated. The CB[8] was synthesized and characterized by 1H NMR, IR, ESI-MS spectra, SEM-EDAX, Zeta-potential and BET-analysis. The adsorption mechanism was due to the coordination between CB[8] molecule and Pb^2＋ ions.
基金Ministry of Science and Technology of China(Nos. 2011CB932503 and 2009CB930402)National Natural Science Foundation of China(No.91227203) are acknowledged for their financial support
文摘A novel supramolecular graft copolymer （SGP） composed of viologen-containing copolymer （P（DMA-co- diEV）） as the main chain and Np ended PNIPAM （Np-PNIPAm） as the grafts is prepared （DMA： N,N- dimethylacryamide, diEV： ethylviologen dimer, Np： naphthalene, PNIPAM： poly（N-isopropylacrylamide））. The grafting is based on the triple complexation among a host of cucurbit[8]uril （CB[8]） and two vips of diEV and Np, which is characterized by UV-vis spectra and ITC. Temperature sensitive property of PNIPAm moiety allows SGP to self-assemble into non-covalently connected micelle （NCCM） at high temperature. The micelles are sensitive to reducing agents, for example Na2S203, which breaks the current inclusion complex pair and induces aggregation.
基金the National Natural Science Foundation of China(No.21861011)the Major Program for Creative Research Groups ofGuizhou Provincial Education Department(No.2017-028)+1 种基金the Innovation Program for High-level Talents of Guizhou Province(No.2016-5657)the Science and Technology Fund of Guizhou Province(Nos.2016-1030,2018-5781)are gratefully acknowledged for financial support。
文摘We report herein a new fluorescent probe for the selective recognition and determination of dodine among 20 different pesticides.This fluorescent probe was assembled through host-vip complexation between cucurbit[10]uril(Q[10]) and aminopropyl-1-pyrenebutanamide(PBA) and is designated as PBA@Q[10].Addition of dodine to PBA@Q[10] results in a dramatic enhancement of fluorescence intensity at 390 nm,accompanied by fluorescence quenching at 488 nm.On this basis,the detection limit is 6.78 × 10^(-7) mol/L.The response mechanism is a competitive interaction:dodine occupies the cavity of Q[10] and forces PBA to leave.
基金supported by the Science and Technology Development Fund,Macao SAR(No.0007/2020/A)International Partnership Program of Chinese Academy of Sciences(No.153B42KYSB20200004 to X.Zhou and R.Wang)+2 种基金the Strategic Priority Research Program of CAS(No.XDB29010300)the National Natural Science Foundation of China(Nos.21871301,22071275,31970169,31800140,31800140 and 31670161)the Yunde Hou Academician Fund from National Institute for Viral Disease Control and Prevention(No.2019HYDQNJJ10)。
文摘The wide-spreading SARS-CoV-2 virus has put the world into boiling water for more than a year,however pharmacological therapies to act effectively against coronavirus disease 2019(COVID-19)remain elusive.Chloroquine(CQ),an antimalarial drug,was found to exhibit promising antiviral activity in vitro and in vivo at a high dosage,thus CQ was approved by the FDA for the emergency use authorization(EUA)in the fight against COVID-19 in the US,but later was revoked the EUA status due to the severe clinical toxicity.Herein,we show that supramolecular formulation of CQ by a macrocyclic host,curcurbit[7]uril(CB[7]),reduced its non-specific toxicity and improved its antiviral activity against coronavirus,working in synergy with CB[7].CB[7]was found to form 1:1 host-vip complexes with CQ,with a binding constant of$104 L/mol.The CQ-CB[7]formulation decreased the cytotoxicity of CQ against Vero E6 and L-02 cell lines.In particular,the cytotoxicity of CQ(60 mmol/L)against both Vero E6 cell line and L-02 cell lines was completely inhibited in the presence of 300 mmol/L and 600 mmol/L CB[7],respectively.Furthermore,the CB[7]alone showed astonishing antiviral activity in SARS-CoV-2 infected Vero E6 cells and mouse hepatitis virus strain A59(MHV-A59)infected N2 A cells,and synergistically improved the antiviral activity of CQ-CB[7],suggesting that CB[7]-based CQ formulation has a great potential as a safe and effective antiviral agent against SARS-CoV-2 and other coronavirus.
