This study reviews light-responsive polymers in various applications,including drug delivery,information storage,sensor,self-healing material,antibacterial or anti-fouling,and environmental applications.Light-responsi...This study reviews light-responsive polymers in various applications,including drug delivery,information storage,sensor,self-healing material,antibacterial or anti-fouling,and environmental applications.Light-responsive polymers are a new material type being developed for various medical,electronics,engineering,and environmental applications.The working principle of light-responsive materials is based on metalligand interactions or non-covalent interactions between polymer functional groups,metal ions,and other filler functional groups.Light irradiation causes physical and mechanical changes in drug delivery and antibacterial systems,which results in the materials releasing more drugs or antibacterial substances.When materials in information storage devices and sensors are exposed to light,they can change color or glow.This has been applied for data storage to reveal QR codes under UV light.Additionally,this review discusses the thermodynamic aspects and computer modeling of light-responsive materials to emphasize the importance and development of these materials.Finally,light-responsive polymer development for various applications is presented.展开更多
To investigate the non-covalent interaction between cyclodextrins (CD) and lithium ion, a stoichiometry of α-CD, β-CD, heptakis(2,6-di-O-methyl)-β-CD (DM-β-CD), or heptakis(2,3,6-tri-O-methyl)-β-CD (TM-...To investigate the non-covalent interaction between cyclodextrins (CD) and lithium ion, a stoichiometry of α-CD, β-CD, heptakis(2,6-di-O-methyl)-β-CD (DM-β-CD), or heptakis(2,3,6-tri-O-methyl)-β-CD (TM-β-CD) was mixed with lithium salt, respectively, and then incubated at room temperature for 10 min to reach the equilibrium. In posi- tive mode, the electrospray ionization mass spectrometry (ESI-MS) results demonstrated that lithium ion can conjugate to α-, β-, DM-β- or TM-β-CD and form 1:1 stoichiometric non-covalent complexes. The binding of the complexes was further confirmed by collision- induced dissociation. The dissociation constants Kdl of four complexes (Li+α-CD, Li+β- CD, Li+DM-β-CD, and Li+TM-β-CD) were determined by mass spectrometric titration. The results showed Kdl were 18.7, 26.7, 33.6, 30.5 μmol/L for the complexes of Li+ with α-CD, β-CD, DM-β-CD, and TM-β-CD, respectively. Kdl for the Li+ complexes of/3-CD is smaller than that of DM-β-CD due to its steric effect of the partial substituted -CH3. The Kdl for the Li+ complexes of DM-β-CD is nearly in agreement with that of TM-β-CD, indicating Li+ is more likely to locate in the small rim of DM-β-CD's hydrophobic cavity. The DFT results showed through electrostatic interaction, one Li+ can strongly conjugate to four neighboring oxygen atoms. For the (α-CD+Li)+ complex, one Li+ may also situate the small rim of α-CD's hydrophobic cavity to form a non-specific host-vip complex.展开更多
As a type II or III transmembrane glycoprotein, human CD38 is ubiquitously expressed in all mammalian tissues. CD38 is a multi-functional enzyme and a member of the ADP-ribosyl cyclase family, and it catalyzes nicotin...As a type II or III transmembrane glycoprotein, human CD38 is ubiquitously expressed in all mammalian tissues. CD38 is a multi-functional enzyme and a member of the ADP-ribosyl cyclase family, and it catalyzes nicotinamide adenine dinucleotide (NAD^+) and nicotinamide adenine dinucleotide phosphate (NADP+) to two distinct Ca^2+ messengers as follows: cyclic ADP-ribose (cADPR) and nicotinic acid adenine dinucleotide phosphate (NAADP), respectively. Moreover, both cADPR and NAADP mediate mobilization of intracellular Ca^2+ targeting endoplasmic stores and the lysosomes, respectively. In this study, we combined ligand-based and structure-based virtual screening strategies to compare the inhibitor discovery efficacy based on natural substrates and the known inhibitors. The similarity queries towards SPECS database were carried out using ROCS and EON modules of OpenEye software. The hits were further docked to CD38 using AutoDock 4.05 program. In addition, ADME studies were also processed considering solubility in water and membrane permeability. Finally, we identified 17 compotmds-based on natural substrates and 10 compounds based on known inhibitor models. The results showed that the known inhibitor H2-based model was more efficient in virtual screening of CD38 non-covalent inhibitors.展开更多
The synergistic effect of conventional flame-retardant elements and graphene has received extensive attention in the development of a new class of flame retardants. Compared to covalent modification, the noncovalent s...The synergistic effect of conventional flame-retardant elements and graphene has received extensive attention in the development of a new class of flame retardants. Compared to covalent modification, the noncovalent strategy is simpler and expeditious and entirely preserves the original quality of graphene. Thus, non-covalently functionalized graphene oxide(FGO) with a phosphorus–nitrogen compound was successfully prepared via a one-pot process in this study. Polyethyleneimine and FGO were alternatively deposited on the surface of a poly(vinyl alcohol)(PVA) film via layer-by-layer assembly driven by electrostatic interaction, imparting excellent flame retardancy to the coated PVA film. The multilayer FGO-based coating formed a protective shield encapsulating the PVA matrix, effectively blocking the transfer of heat and mass during combustion. The coated PVA has a higher initial decomposition temperature of about 260 °C and a nearly 60% reduction in total heat release than neat PVA does. Our results may have a promising prospect for flame-retardant polymers.展开更多
Herein,we firstly developed a non-covalent glycosylated gold nanoparticles/peptides nanovaccine which is assembled byβ-cyclodextrin(β-CD)based host-vip recognitions.This nanovaccine can generate significant titers...Herein,we firstly developed a non-covalent glycosylated gold nanoparticles/peptides nanovaccine which is assembled byβ-cyclodextrin(β-CD)based host-vip recognitions.This nanovaccine can generate significant titers of antibodies and improve the therapeutic effect against melanoma,suggesting the immunogenicity of peptide antigens can be improved by loading with this carrier.The novel vaccine carrier provides a platform for the transport of various antigens especially T cell-independent antigens.展开更多
A new complex, [Ni2(L)4(H2O)8](1, L1 = 4-(1H-imidazol-4-yl)benzoic acid), has been hydrothermally prepared and characterized by single-crystal X-ray diffraction, IR spectroscopy, elemental analysis and PXRD. C...A new complex, [Ni2(L)4(H2O)8](1, L1 = 4-(1H-imidazol-4-yl)benzoic acid), has been hydrothermally prepared and characterized by single-crystal X-ray diffraction, IR spectroscopy, elemental analysis and PXRD. Complex 1 crystallizes in monoclinic, space group P21/c with α = 22.281(2), b = 7.3959(7), c = 24.978(3) ?, β = 90.876(10), V = 4115.6(7) ?3, Z = 8, C20H22N4O8Ni, Mr = 505.13, Dc = 1.630 g/cm3, μ = 1.001 mm-1, S = 1.080, F(000) = 2096, the final R = 0.452 and wR = 0.1152 for 9380 observed reflections (I 〉 2σ(I)). The result of X-ray diffraction analysis revealed three different kinds of Ni(II) centre mononuclear molecules in the asymmetric unit. The independent mononuclear units are bridged to form a three-dimensional supramolecular polymer by extensive hydrogen bonds and C–H… non-covalent bonding interactions.展开更多
Plant phenolic acids are good sources of antioxidants and sinapic acid(SA)is one of them that can be applied in protein-based food system.However,little research is available regarding interactions between almond prot...Plant phenolic acids are good sources of antioxidants and sinapic acid(SA)is one of them that can be applied in protein-based food system.However,little research is available regarding interactions between almond protein(AP)and SA.In this study,structure-affinity interaction between SA and AP,structure and antioxidant activity of proteins were investigated.Different mathematical models showed that Ka of binding SA and AP were 3.27×10^4 L/mol and 3.08×10^4 L/mol.CD(Circular dichroism)spectroscopy and FT-IR(Fourier transform infrared)spectroscopy showed that the amount of random coil andα-helix decreased whileβ-sheet increased in AP-SA complex.In combination,the interaction model of AP-SA complex was static quenching and attributed to hydrophobic interaction.Further,AP-SA complex exerted better DPPH radical scavenging ability(36.97±0.78%),ABTS+radical scavenging ability(47.26±0.45%),and higher ORAC value(2.41±0.23 M trolox/g)compared to AP.In the further,SA can be applied in protein matrix to improve film stability,gel strength and restraining fat oxidation degradation.展开更多
The non-covalent interaction between apigenin (API) and different functional monomers (α-methylacrylic acid (MAA), acrylamide (AM), 2-vinylpyridine (2-Vpy) and combined functional monomers (AM/2-Vpy)) was determined ...The non-covalent interaction between apigenin (API) and different functional monomers (α-methylacrylic acid (MAA), acrylamide (AM), 2-vinylpyridine (2-Vpy) and combined functional monomers (AM/2-Vpy)) was determined by UV spectrometry, and a series of apigenin molecularly imprinted polymers (API-MIPs) was synthesized with different functional monomers through molecular imprinting technology. The relationship between the non-covalent interaction of template/functional monomer and absorption of MIPs also was studied. The results showed that the order of the strength of the non-covalent interaction between API and different functional monomers in tetrahydrofuran (THF) is as follows: 2-Vpy> AM/2-Vpy>AM>MAA, which is positive correlation to the absorption capability of corresponding MIPs, and 2-Vpy is the optimum functional monomer among the used monomer for preparing API- MIPs.展开更多
Diethyl flavon-7-yl phosphate was synthesized by modified Atheron-Todd reaction. The result of ESI shows that the phosphated flavonoids possess stronger binding affinities toward proteins such as myoglobin, insulin an...Diethyl flavon-7-yl phosphate was synthesized by modified Atheron-Todd reaction. The result of ESI shows that the phosphated flavonoids possess stronger binding affinities toward proteins such as myoglobin, insulin and lysozyme and are easier to form the non-covalent complexes with them.展开更多
The non-covalent complexes between lappaconitine (LA) and β-cyclodextrin (β-CD) have been detected and characterized by electrospray ionization combined with ion trap tandem mass spectrometry (ESI-MSn). The ex...The non-covalent complexes between lappaconitine (LA) and β-cyclodextrin (β-CD) have been detected and characterized by electrospray ionization combined with ion trap tandem mass spectrometry (ESI-MSn). The experimental results showed that only 1:1 non-covalent complex can be formed in different starting molar ratios of LA to β-CD. Furthermore, the diagnostic fragmentation of the β-CD-LA complex, with a significant contribution of covalent fragmentation of LA leaving the N-acetyl anthranoyl (AN) moiety inserted to β-CD, provided the convincing evidence for the formation of non-covalent complex between LA and β-CD and the cite of LA molecule included to cavity of β-CD assigned to AN residue.展开更多
Aggregate engineering of non-covalent networks endows supramolecular polymers with thermo-mechanical versatility,stimuli-responsive phase transitions and intrinsic damage-healing capabilities.However,most non-covalent...Aggregate engineering of non-covalent networks endows supramolecular polymers with thermo-mechanical versatility,stimuli-responsive phase transitions and intrinsic damage-healing capabilities.However,most non-covalent networks are vulnerable at elevated temperatures,which suppresses the robustness of supramolecular polymers.Herein,ureidocytosine(UCy)motifs,which are capable of forming extensive non-covalent networks and thus robust molecular aggregates via multivalent hydrogen bonds and aromatic stackings,are proposed to enable precise programming of the thermo-mechanical versatility.Molecular simulations reveal that the enthalpic contributions from the UCy aggregates play dominant roles to compensate the entropic loss from the redistributions of polymeric spacers and stabilize the non-covalent networks over wide temperature windows.Such aggregate-level strategy offers prospects for applications which require thermo-mechanical versatility of supramolecular polymers,such as 3D printing,microfabrication and damage-healing coating.展开更多
Vectored non-covalent interactions—mainly hydrogen bonding and aromatic interactions—extensively contribute to(bio)-organic self-assembling processes and significantly impact the physicochemical properties of the as...Vectored non-covalent interactions—mainly hydrogen bonding and aromatic interactions—extensively contribute to(bio)-organic self-assembling processes and significantly impact the physicochemical properties of the associated superstructures.However,vectored non-covalent interaction-driven assembly occursmainly along one-dimensional(1D)or three-dimensional(3D)directions,and a two-dimensional(2D)orientation,especially that of multilayered,graphene-like assembly,has been reported less.In this present research,by introducing amino,hydroxyl,and phenyl moieties to the triazine skeleton,supramolecular layered assembly is achieved by vectored non-covalent interactions.The planar hydrogen bonding network results in high stability,with a thermal sustainability of up to about 330°C and a Young’s modulus of up to about 40 GPa.Upon introducing wrinkles by biased hydrogen bonding or aromatic interactions to disturb the planar organization,the stability attenuates.However,the intertwined aromatic interactions prompt a red edge excitation shift effect inside the assemblies,inducing broad-spectrum fluorescence covering nearly the entire visible light region(400–650 nm).We show that bionic,superhydrophobic,pillar-like arrays with contact angles of up to about 170°can be engineered by aromatic interactions using a physical vapor deposition approach,which cannot be realized through hydrogen bonding.Our findings show the feasibility of 2D assembly with engineerable properties by modulating vectored non-covalent interactions.展开更多
The main protease(M^(pro))of SARS-CoV-2 is an attractive target in anti-COVID-19 therapy for its high conservation and major role in the virus life cycle.The covalent M^(pro)inhibitor nirmatrelvir(in combination with ...The main protease(M^(pro))of SARS-CoV-2 is an attractive target in anti-COVID-19 therapy for its high conservation and major role in the virus life cycle.The covalent M^(pro)inhibitor nirmatrelvir(in combination with ritonavir,a pharmacokinetic enhancer)and the non-covalent inhibitor ensitrelvir have shown efficacy in clinical trials and have been approved for therapeutic use.Effective antiviral drugs are needed to fight the pandemic,while non-covalent M^(pro)inhibitors could be promising alternatives due to their high selectivity and favorable druggability.Numerous non-covalent M^(pro)inhibitors with desirable properties have been developed based on available crystal structures of M^(pro).In this article,we describe medicinal chemistry strategies applied for the discovery and optimization of non-covalent M^(pro)inhibitors,followed by a general overview and critical analysis of the available information.Prospective viewpoints and insights into current strategies for the development of non-covalent M^(pro)inhibitors are also discussed.展开更多
To the Editor:The papain-like protease(PL^(pro)),as one of the most important proteases of SARS-CoV-2,has emerged as a highly promising target protein,its inhibitor probably holds dual potentials,namely blocking the c...To the Editor:The papain-like protease(PL^(pro)),as one of the most important proteases of SARS-CoV-2,has emerged as a highly promising target protein,its inhibitor probably holds dual potentials,namely blocking the cleavage of viral polyprotein and intercepting the deubiquitination and deISGylation functions to restore antiviral immunity1.展开更多
Daidzein (7,4'-dihydroxyisoflavone) was phosphorylated by a modified Atherton-Todd reaction. The structures of the five target product, were determined by X-ray, IR, NMR and ESI-MS. Electrospray ionization results ...Daidzein (7,4'-dihydroxyisoflavone) was phosphorylated by a modified Atherton-Todd reaction. The structures of the five target product, were determined by X-ray, IR, NMR and ESI-MS. Electrospray ionization results show that in the gas phase all the phosphorylated daidzein derivatives could form non-covalent complexes with the protein lysozyme, while non-covalent complexes were not detected in the mixed solution of daidzein with lysozyme. Relative affinity of every non-covalent complex was obtained according to its different decomposition orifice voltage.展开更多
Seryl-Histidine dipeptide(Ser-His) has been previously reported to be capable of cleaving DNAs and carboxyl esters,as well as proteins.The protein cleavage mechanism has not been addressed yet.As an initial step of pr...Seryl-Histidine dipeptide(Ser-His) has been previously reported to be capable of cleaving DNAs and carboxyl esters,as well as proteins.The protein cleavage mechanism has not been addressed yet.As an initial step of protein cleavage activity,the non-covalent binding affinity of Ser-His for proteins is a crucial prerequisite.In this work,we took cyclophilin A(CyPA) as a substrate protein,and evaluated the non-covalent interaction between CyPA and Ser-His using a combination of NMR spectroscopy and molecular modeling approach.Two independent Ser-His binding sites on CyPA were detected using 15N-1H heteronuclear single-quantum coherence(HSQC) spectra.Each binding site binds one Ser-His molecule.Dissociation constants,Kd1 and Kd2,were estimated to be 2.07 and 6.66 mmol/L,respectively,indicative of the weak non-covalent interaction between Ser-His and CyPA.Based on molecular modeling results,we suggest that both the α-amino and the side chain hydroxyl group of Ser-His are crucial for the non-covalent interaction between Ser-His and CyPA.This work sheds light on the molecular mechanism of Ser-His and its analogues cleaving proteins.展开更多
We have developed an efficient strategy for the non-covalent functionalization of multi-walled carbon nanotubes(MWCNTs)which allows a biomimetic presentation of carbohydrates on their surface byπ-πstacking interacti...We have developed an efficient strategy for the non-covalent functionalization of multi-walled carbon nanotubes(MWCNTs)which allows a biomimetic presentation of carbohydrates on their surface byπ-πstacking interactions.The strategy is based on the use of sugar-based amphiphiles functionalized with tetrabenzo[a,c,g,i]fluorene(Tbf),a polyaromatic compound with a topology that resembles a butterfly with open wings.The new carbohydrate-tethered Tbf amphiphiles have been synthesized in a straightforward manner using click chemistry.The reported method has been developed in order to improve the rather low ability of pyrene-based systems to exfoliate MWCNTs in water.By means of thermogravimetric analysis(TGA),ultraviolet(UV),infrared(IR),and fluorescence spectroscopies the interaction between MWCNTs and the Tbf group has been found to be stronger than those involving pyrene-based amphiphilic carbohydrates.The resulting aggregates with a multivalent sugar exposition on their surface are able to engage in specific ligand-lectin interactions similar to glycoconjugates on a cell membrane.展开更多
An ESI-MS method for studying the non-covalent bond complex of rhFKBP12 with its nonimmunosuppressive ligands was developed. The method was used to screen out three com-pounds capable of binding to rhFKBP12 non-covale...An ESI-MS method for studying the non-covalent bond complex of rhFKBP12 with its nonimmunosuppressive ligands was developed. The method was used to screen out three com-pounds capable of binding to rhFKBP12 non-covalently from 52 compounds. By competing binding experiment, the binding site and the relative binding strength of these three compounds 000107, 000308 and A2B12 with rhFKBP12 were measured. All of them have the same binding site as FK506 does. X-ray crystalline diffraction experiment of non-covalent bond complex of 000107, 000308 with rhFKBP12 by Tsinghua University showed the same results. Among them 000308 has good effect on stimulating neurite to grow in chicken sensory neuronal cultures.展开更多
The molecular non-covalent interaction often originates from the electrostatic attraction and accords with the Langmuir isothermal adsorption. The sodium dodecyl benzene sulfonate (SDBS)-polychrome blue B (PCB)-protei...The molecular non-covalent interaction often originates from the electrostatic attraction and accords with the Langmuir isothermal adsorption. The sodium dodecyl benzene sulfonate (SDBS)-polychrome blue B (PCB)-protein [bovine serum albumin (BSA), ovalbumin (OVA) and myoglobin (MB)] ternary reaction has been investigated at pH 3.88. Protein to replace PCB from the PCB-SDBS binding product was used to characterize the assembly of an invisible-spectral compound, SDBS, on proteins by measuring the variation of PCB light-absorption by the microsurface adsorption-spectral correction (MSASQ technique. The effect of ionic strength and temperature on the aggregation was studied. Results showed that the aggregates SDBS(92)(.)BSA, SDBS(58)(.)OVA and (SDBS15MB)-M-. at 30 degreesC and SDBS(83)(.)BSA, SDBS(39)(.)OVA and (SDBS10MB)-M-. at 50 degreesC are formed.展开更多
Recent years have witnessed the fabrication of various non-covalent interaction-based molecular electronic devices.In the noncovalent interaction-based molecular devices,the strength of the interfacial coupling betwee...Recent years have witnessed the fabrication of various non-covalent interaction-based molecular electronic devices.In the noncovalent interaction-based molecular devices,the strength of the interfacial coupling between molecule and electrode is weakened compared to that of the covalent interaction-based molecular devices,which provides wide applications in fabricating versatile molecular devices.In this review,we start with the methods capable of fabricating graphene-based nanogaps,and the following routes to construct non-covalent interaction-based molecular junctions with graphene electrodes.Then we give an introduction to the reported non-covalent interaction-based molecular devices with graphene electrodes equipped with different electrical functions.Moreover,we summarize the recent progress in the design and fabrication of new-type molecular devices based on graphene and graphene-like two-dimensional(2D)materials.The review ends with a prospect on the challenges and opportunities of non-covalent interaction-based molecular electronics in the near future.展开更多
基金the Franco-Thai Cooperation Programme in Higher Education and Research(Franco-Thai Mobility Programme/PHC SIAM)Year 2024-2025。
文摘This study reviews light-responsive polymers in various applications,including drug delivery,information storage,sensor,self-healing material,antibacterial or anti-fouling,and environmental applications.Light-responsive polymers are a new material type being developed for various medical,electronics,engineering,and environmental applications.The working principle of light-responsive materials is based on metalligand interactions or non-covalent interactions between polymer functional groups,metal ions,and other filler functional groups.Light irradiation causes physical and mechanical changes in drug delivery and antibacterial systems,which results in the materials releasing more drugs or antibacterial substances.When materials in information storage devices and sensors are exposed to light,they can change color or glow.This has been applied for data storage to reveal QR codes under UV light.Additionally,this review discusses the thermodynamic aspects and computer modeling of light-responsive materials to emphasize the importance and development of these materials.Finally,light-responsive polymer development for various applications is presented.
文摘To investigate the non-covalent interaction between cyclodextrins (CD) and lithium ion, a stoichiometry of α-CD, β-CD, heptakis(2,6-di-O-methyl)-β-CD (DM-β-CD), or heptakis(2,3,6-tri-O-methyl)-β-CD (TM-β-CD) was mixed with lithium salt, respectively, and then incubated at room temperature for 10 min to reach the equilibrium. In posi- tive mode, the electrospray ionization mass spectrometry (ESI-MS) results demonstrated that lithium ion can conjugate to α-, β-, DM-β- or TM-β-CD and form 1:1 stoichiometric non-covalent complexes. The binding of the complexes was further confirmed by collision- induced dissociation. The dissociation constants Kdl of four complexes (Li+α-CD, Li+β- CD, Li+DM-β-CD, and Li+TM-β-CD) were determined by mass spectrometric titration. The results showed Kdl were 18.7, 26.7, 33.6, 30.5 μmol/L for the complexes of Li+ with α-CD, β-CD, DM-β-CD, and TM-β-CD, respectively. Kdl for the Li+ complexes of/3-CD is smaller than that of DM-β-CD due to its steric effect of the partial substituted -CH3. The Kdl for the Li+ complexes of DM-β-CD is nearly in agreement with that of TM-β-CD, indicating Li+ is more likely to locate in the small rim of DM-β-CD's hydrophobic cavity. The DFT results showed through electrostatic interaction, one Li+ can strongly conjugate to four neighboring oxygen atoms. For the (α-CD+Li)+ complex, one Li+ may also situate the small rim of α-CD's hydrophobic cavity to form a non-specific host-vip complex.
基金National Natural Science Foundation of China(Grant No.21272017 and 81172917)
文摘As a type II or III transmembrane glycoprotein, human CD38 is ubiquitously expressed in all mammalian tissues. CD38 is a multi-functional enzyme and a member of the ADP-ribosyl cyclase family, and it catalyzes nicotinamide adenine dinucleotide (NAD^+) and nicotinamide adenine dinucleotide phosphate (NADP+) to two distinct Ca^2+ messengers as follows: cyclic ADP-ribose (cADPR) and nicotinic acid adenine dinucleotide phosphate (NAADP), respectively. Moreover, both cADPR and NAADP mediate mobilization of intracellular Ca^2+ targeting endoplasmic stores and the lysosomes, respectively. In this study, we combined ligand-based and structure-based virtual screening strategies to compare the inhibitor discovery efficacy based on natural substrates and the known inhibitors. The similarity queries towards SPECS database were carried out using ROCS and EON modules of OpenEye software. The hits were further docked to CD38 using AutoDock 4.05 program. In addition, ADME studies were also processed considering solubility in water and membrane permeability. Finally, we identified 17 compotmds-based on natural substrates and 10 compounds based on known inhibitor models. The results showed that the known inhibitor H2-based model was more efficient in virtual screening of CD38 non-covalent inhibitors.
基金supported by National Natural Science Foundation of China (No. 51473095)the Program of Innovative Research Team for Young Scientists of Sichuan Province (2016TD0010)
文摘The synergistic effect of conventional flame-retardant elements and graphene has received extensive attention in the development of a new class of flame retardants. Compared to covalent modification, the noncovalent strategy is simpler and expeditious and entirely preserves the original quality of graphene. Thus, non-covalently functionalized graphene oxide(FGO) with a phosphorus–nitrogen compound was successfully prepared via a one-pot process in this study. Polyethyleneimine and FGO were alternatively deposited on the surface of a poly(vinyl alcohol)(PVA) film via layer-by-layer assembly driven by electrostatic interaction, imparting excellent flame retardancy to the coated PVA film. The multilayer FGO-based coating formed a protective shield encapsulating the PVA matrix, effectively blocking the transfer of heat and mass during combustion. The coated PVA has a higher initial decomposition temperature of about 260 °C and a nearly 60% reduction in total heat release than neat PVA does. Our results may have a promising prospect for flame-retardant polymers.
基金the Guangdong Key Laboratory for Translational Cancer Research of Chinese Medicine(No.20188030322011)the National Natural Science Foundation of China(No.81773580)。
文摘Herein,we firstly developed a non-covalent glycosylated gold nanoparticles/peptides nanovaccine which is assembled byβ-cyclodextrin(β-CD)based host-vip recognitions.This nanovaccine can generate significant titers of antibodies and improve the therapeutic effect against melanoma,suggesting the immunogenicity of peptide antigens can be improved by loading with this carrier.The novel vaccine carrier provides a platform for the transport of various antigens especially T cell-independent antigens.
基金supported by the National Natural Science Foundation of China(Nos.21171040 and 21302019)
文摘A new complex, [Ni2(L)4(H2O)8](1, L1 = 4-(1H-imidazol-4-yl)benzoic acid), has been hydrothermally prepared and characterized by single-crystal X-ray diffraction, IR spectroscopy, elemental analysis and PXRD. Complex 1 crystallizes in monoclinic, space group P21/c with α = 22.281(2), b = 7.3959(7), c = 24.978(3) ?, β = 90.876(10), V = 4115.6(7) ?3, Z = 8, C20H22N4O8Ni, Mr = 505.13, Dc = 1.630 g/cm3, μ = 1.001 mm-1, S = 1.080, F(000) = 2096, the final R = 0.452 and wR = 0.1152 for 9380 observed reflections (I 〉 2σ(I)). The result of X-ray diffraction analysis revealed three different kinds of Ni(II) centre mononuclear molecules in the asymmetric unit. The independent mononuclear units are bridged to form a three-dimensional supramolecular polymer by extensive hydrogen bonds and C–H… non-covalent bonding interactions.
基金supported by the National Key Research and Development Program of China (2016YFD0401401)The Technological innovation project of Hubei Province (2017ABA142)+2 种基金The Science and Technology Plan Project of Tibet Autonomous Region (XZ201901NA04)The Science and Technology Plan Project of Hunan Science (2017NK2212)The Agricultural Science and Technology Innovation Project of Chinese Academy of Agricultural Sciences (CAAS-ASTIP-2016-OCRI)
文摘Plant phenolic acids are good sources of antioxidants and sinapic acid(SA)is one of them that can be applied in protein-based food system.However,little research is available regarding interactions between almond protein(AP)and SA.In this study,structure-affinity interaction between SA and AP,structure and antioxidant activity of proteins were investigated.Different mathematical models showed that Ka of binding SA and AP were 3.27×10^4 L/mol and 3.08×10^4 L/mol.CD(Circular dichroism)spectroscopy and FT-IR(Fourier transform infrared)spectroscopy showed that the amount of random coil andα-helix decreased whileβ-sheet increased in AP-SA complex.In combination,the interaction model of AP-SA complex was static quenching and attributed to hydrophobic interaction.Further,AP-SA complex exerted better DPPH radical scavenging ability(36.97±0.78%),ABTS+radical scavenging ability(47.26±0.45%),and higher ORAC value(2.41±0.23 M trolox/g)compared to AP.In the further,SA can be applied in protein matrix to improve film stability,gel strength and restraining fat oxidation degradation.
基金National Natural Science Foundation of China (No. 20877036)Advanced Talent Foundation of Jiangsu University (No. 04JBG017).
文摘The non-covalent interaction between apigenin (API) and different functional monomers (α-methylacrylic acid (MAA), acrylamide (AM), 2-vinylpyridine (2-Vpy) and combined functional monomers (AM/2-Vpy)) was determined by UV spectrometry, and a series of apigenin molecularly imprinted polymers (API-MIPs) was synthesized with different functional monomers through molecular imprinting technology. The relationship between the non-covalent interaction of template/functional monomer and absorption of MIPs also was studied. The results showed that the order of the strength of the non-covalent interaction between API and different functional monomers in tetrahydrofuran (THF) is as follows: 2-Vpy> AM/2-Vpy>AM>MAA, which is positive correlation to the absorption capability of corresponding MIPs, and 2-Vpy is the optimum functional monomer among the used monomer for preparing API- MIPs.
文摘Diethyl flavon-7-yl phosphate was synthesized by modified Atheron-Todd reaction. The result of ESI shows that the phosphated flavonoids possess stronger binding affinities toward proteins such as myoglobin, insulin and lysozyme and are easier to form the non-covalent complexes with them.
基金supported by the National Natural Science Foundation of China(No.30472134,20173057)the State Great Basic Research Project of China(No.2003CCA03100)the Great Research Project of Chinese Academy of Sciences(No.KGCX2-SW-213-06).
文摘The non-covalent complexes between lappaconitine (LA) and β-cyclodextrin (β-CD) have been detected and characterized by electrospray ionization combined with ion trap tandem mass spectrometry (ESI-MSn). The experimental results showed that only 1:1 non-covalent complex can be formed in different starting molar ratios of LA to β-CD. Furthermore, the diagnostic fragmentation of the β-CD-LA complex, with a significant contribution of covalent fragmentation of LA leaving the N-acetyl anthranoyl (AN) moiety inserted to β-CD, provided the convincing evidence for the formation of non-covalent complex between LA and β-CD and the cite of LA molecule included to cavity of β-CD assigned to AN residue.
基金supported by the Research Grant Council of Hong Kong(No.CityU 11305219)City University of Hong Kong(Nos.6000685 and 9610348)Research Grant Council of Hong Kong(No.C1025-14E).
文摘Aggregate engineering of non-covalent networks endows supramolecular polymers with thermo-mechanical versatility,stimuli-responsive phase transitions and intrinsic damage-healing capabilities.However,most non-covalent networks are vulnerable at elevated temperatures,which suppresses the robustness of supramolecular polymers.Herein,ureidocytosine(UCy)motifs,which are capable of forming extensive non-covalent networks and thus robust molecular aggregates via multivalent hydrogen bonds and aromatic stackings,are proposed to enable precise programming of the thermo-mechanical versatility.Molecular simulations reveal that the enthalpic contributions from the UCy aggregates play dominant roles to compensate the entropic loss from the redistributions of polymeric spacers and stabilize the non-covalent networks over wide temperature windows.Such aggregate-level strategy offers prospects for applications which require thermo-mechanical versatility of supramolecular polymers,such as 3D printing,microfabrication and damage-healing coating.
基金supported by the Fund for Creative Research Groups of National Natural Science Foundation of China (No. 51821093)the National Natural Science Foundation of China (Nos. 52175551, 52075484)(KT and DM)+2 种基金the National Key Research and Development Program (SQ2021YFE010405)(KT)Science Foundation Ireland (SFI) through awards Nos. 15/CDA/3491and 12/RC/2275_P2 (DT)computing resources at the SFI/Higher Education Authority Irish Center for High-End Computing (ICHEC)(SG and DT)
文摘Vectored non-covalent interactions—mainly hydrogen bonding and aromatic interactions—extensively contribute to(bio)-organic self-assembling processes and significantly impact the physicochemical properties of the associated superstructures.However,vectored non-covalent interaction-driven assembly occursmainly along one-dimensional(1D)or three-dimensional(3D)directions,and a two-dimensional(2D)orientation,especially that of multilayered,graphene-like assembly,has been reported less.In this present research,by introducing amino,hydroxyl,and phenyl moieties to the triazine skeleton,supramolecular layered assembly is achieved by vectored non-covalent interactions.The planar hydrogen bonding network results in high stability,with a thermal sustainability of up to about 330°C and a Young’s modulus of up to about 40 GPa.Upon introducing wrinkles by biased hydrogen bonding or aromatic interactions to disturb the planar organization,the stability attenuates.However,the intertwined aromatic interactions prompt a red edge excitation shift effect inside the assemblies,inducing broad-spectrum fluorescence covering nearly the entire visible light region(400–650 nm).We show that bionic,superhydrophobic,pillar-like arrays with contact angles of up to about 170°can be engineered by aromatic interactions using a physical vapor deposition approach,which cannot be realized through hydrogen bonding.Our findings show the feasibility of 2D assembly with engineerable properties by modulating vectored non-covalent interactions.
基金We gratefully acknowledge financial support from Major Basic Research Project of Shandong Provincial Natural Science Foundation(ZR2021ZD17,China)Science Foundation for Outstanding Young Scholars of Shandong Province(ZR2020JQ31,China)+4 种基金Foreign Cultural and Educational Experts Project(GXL20200015001,China)Guangdong Basic and Applied Basic Research Foundation(2021A1515110740,China)China Postdoctoral Science Foundation(2021M702003)This work was supported in part by the Ministry of Science and Innovation of Spain through grant PID2019-104176RBI00/AEI/10.13039/501100011033 awarded to Luis Menéndez-AriasAn institutional grant of the Fundación Ramón Areces(Madrid,Spain)to the CBMSO is also acknowledged.Luis Menéndez-Arias is member of the Global Virus Network.
文摘The main protease(M^(pro))of SARS-CoV-2 is an attractive target in anti-COVID-19 therapy for its high conservation and major role in the virus life cycle.The covalent M^(pro)inhibitor nirmatrelvir(in combination with ritonavir,a pharmacokinetic enhancer)and the non-covalent inhibitor ensitrelvir have shown efficacy in clinical trials and have been approved for therapeutic use.Effective antiviral drugs are needed to fight the pandemic,while non-covalent M^(pro)inhibitors could be promising alternatives due to their high selectivity and favorable druggability.Numerous non-covalent M^(pro)inhibitors with desirable properties have been developed based on available crystal structures of M^(pro).In this article,we describe medicinal chemistry strategies applied for the discovery and optimization of non-covalent M^(pro)inhibitors,followed by a general overview and critical analysis of the available information.Prospective viewpoints and insights into current strategies for the development of non-covalent M^(pro)inhibitors are also discussed.
基金National Natural Science Foundation of China(82151219,82130105)the Strategic Priority Research Program of Chinese Academy of Sciences(SIMM010109,SIMM010111)Shanghai Institute of Materia Medica of Chinese Academy of Sciences(SIMM0120231003)for the financial support.
文摘To the Editor:The papain-like protease(PL^(pro)),as one of the most important proteases of SARS-CoV-2,has emerged as a highly promising target protein,its inhibitor probably holds dual potentials,namely blocking the cleavage of viral polyprotein and intercepting the deubiquitination and deISGylation functions to restore antiviral immunity1.
基金Project supported by the National Natural Science Foundation of China (Nos. 20132020 and 20175026) and Henan Academic Foundation of Science and Technology.
文摘Daidzein (7,4'-dihydroxyisoflavone) was phosphorylated by a modified Atherton-Todd reaction. The structures of the five target product, were determined by X-ray, IR, NMR and ESI-MS. Electrospray ionization results show that in the gas phase all the phosphorylated daidzein derivatives could form non-covalent complexes with the protein lysozyme, while non-covalent complexes were not detected in the mixed solution of daidzein with lysozyme. Relative affinity of every non-covalent complex was obtained according to its different decomposition orifice voltage.
基金supported by grants from the National Natural Science Foundation of China ( 20732004, 30730026, 20805037)the Ministry of Science and Technology of China (2007CB914304)
文摘Seryl-Histidine dipeptide(Ser-His) has been previously reported to be capable of cleaving DNAs and carboxyl esters,as well as proteins.The protein cleavage mechanism has not been addressed yet.As an initial step of protein cleavage activity,the non-covalent binding affinity of Ser-His for proteins is a crucial prerequisite.In this work,we took cyclophilin A(CyPA) as a substrate protein,and evaluated the non-covalent interaction between CyPA and Ser-His using a combination of NMR spectroscopy and molecular modeling approach.Two independent Ser-His binding sites on CyPA were detected using 15N-1H heteronuclear single-quantum coherence(HSQC) spectra.Each binding site binds one Ser-His molecule.Dissociation constants,Kd1 and Kd2,were estimated to be 2.07 and 6.66 mmol/L,respectively,indicative of the weak non-covalent interaction between Ser-His and CyPA.Based on molecular modeling results,we suggest that both the α-amino and the side chain hydroxyl group of Ser-His are crucial for the non-covalent interaction between Ser-His and CyPA.This work sheds light on the molecular mechanism of Ser-His and its analogues cleaving proteins.
基金This work was supported by the Ministerio de Ciencia e Innovación(grant No.CTQ2010-21755-CO2-00)the Junta de Andalucía(grant Nos.P06-FQM-01852 and P07-FQM-2774)the Centre National de la Recherche Scientifique(France)and the Consejo Superior de Investigaciones Científicas(Egide Picasso 09543XA and Projets Internationaux de Cooperation Scientifiques Program 2008-2010).
文摘We have developed an efficient strategy for the non-covalent functionalization of multi-walled carbon nanotubes(MWCNTs)which allows a biomimetic presentation of carbohydrates on their surface byπ-πstacking interactions.The strategy is based on the use of sugar-based amphiphiles functionalized with tetrabenzo[a,c,g,i]fluorene(Tbf),a polyaromatic compound with a topology that resembles a butterfly with open wings.The new carbohydrate-tethered Tbf amphiphiles have been synthesized in a straightforward manner using click chemistry.The reported method has been developed in order to improve the rather low ability of pyrene-based systems to exfoliate MWCNTs in water.By means of thermogravimetric analysis(TGA),ultraviolet(UV),infrared(IR),and fluorescence spectroscopies the interaction between MWCNTs and the Tbf group has been found to be stronger than those involving pyrene-based amphiphilic carbohydrates.The resulting aggregates with a multivalent sugar exposition on their surface are able to engage in specific ligand-lectin interactions similar to glycoconjugates on a cell membrane.
文摘An ESI-MS method for studying the non-covalent bond complex of rhFKBP12 with its nonimmunosuppressive ligands was developed. The method was used to screen out three com-pounds capable of binding to rhFKBP12 non-covalently from 52 compounds. By competing binding experiment, the binding site and the relative binding strength of these three compounds 000107, 000308 and A2B12 with rhFKBP12 were measured. All of them have the same binding site as FK506 does. X-ray crystalline diffraction experiment of non-covalent bond complex of 000107, 000308 with rhFKBP12 by Tsinghua University showed the same results. Among them 000308 has good effect on stimulating neurite to grow in chicken sensory neuronal cultures.
文摘The molecular non-covalent interaction often originates from the electrostatic attraction and accords with the Langmuir isothermal adsorption. The sodium dodecyl benzene sulfonate (SDBS)-polychrome blue B (PCB)-protein [bovine serum albumin (BSA), ovalbumin (OVA) and myoglobin (MB)] ternary reaction has been investigated at pH 3.88. Protein to replace PCB from the PCB-SDBS binding product was used to characterize the assembly of an invisible-spectral compound, SDBS, on proteins by measuring the variation of PCB light-absorption by the microsurface adsorption-spectral correction (MSASQ technique. The effect of ionic strength and temperature on the aggregation was studied. Results showed that the aggregates SDBS(92)(.)BSA, SDBS(58)(.)OVA and (SDBS15MB)-M-. at 30 degreesC and SDBS(83)(.)BSA, SDBS(39)(.)OVA and (SDBS10MB)-M-. at 50 degreesC are formed.
基金the support from the National Natural Science Foundation of China(Nos.21973079 and 22032004)the National Key R&D Program of China(No.2017YFA0204902)the Fundamental Research Funds for the Central Universities(Xiamen University:No.20720190002).
文摘Recent years have witnessed the fabrication of various non-covalent interaction-based molecular electronic devices.In the noncovalent interaction-based molecular devices,the strength of the interfacial coupling between molecule and electrode is weakened compared to that of the covalent interaction-based molecular devices,which provides wide applications in fabricating versatile molecular devices.In this review,we start with the methods capable of fabricating graphene-based nanogaps,and the following routes to construct non-covalent interaction-based molecular junctions with graphene electrodes.Then we give an introduction to the reported non-covalent interaction-based molecular devices with graphene electrodes equipped with different electrical functions.Moreover,we summarize the recent progress in the design and fabrication of new-type molecular devices based on graphene and graphene-like two-dimensional(2D)materials.The review ends with a prospect on the challenges and opportunities of non-covalent interaction-based molecular electronics in the near future.