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1.
Nat Commun ; 12(1): 4993, 2021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-34404798

RESUMO

Dissipative self-assembly, which requires a continuous supply of fuel to maintain the assembled states far from equilibrium, is the foundation of biological systems. Among a variety of fuels, light, the original fuel of natural dissipative self-assembly, is fundamentally important but remains a challenge to introduce into artificial dissipative self-assemblies. Here, we report an artificial dissipative self-assembly system that is constructed from light-induced amphiphiles. Such dissipative supramolecular assembly is easily performed using protonated sulfonato-merocyanine and chitosan based molecular and macromolecular components in water. Light irradiation induces the assembly of supramolecular nanoparticles, which spontaneously disassemble in the dark due to thermal back relaxation of the molecular switch. Owing to the presence of light-induced amphiphiles and the thermal dissociation mechanism, the lifetimes of these transient supramolecular nanoparticles are highly sensitive to temperature and light power and range from several minutes to hours. By incorporating various fluorophores into transient supramolecular nanoparticles, the processes of aggregation-induced emission and aggregation-caused quenching, along with periodic variations in fluorescent color over time, have been demonstrated. Transient supramolecular assemblies, which act as fluorescence modulators, can also function in human hepatocellular cancer cells.


Assuntos
Corantes Fluorescentes/química , Nanopartículas/química , Água/química , Fluorescência , Células Hep G2 , Humanos , Cinética , Substâncias Macromoleculares , Temperatura
2.
Angew Chem Int Ed Engl ; 60(20): 11247-11251, 2021 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-33655581

RESUMO

Bioinspired smart materials with synergistic allochroic luminescence and complex deformation are expected to play an important role in many areas of science and technology. However, it is still challenging to fabricate such soft actuators with high programmability that can be manipulated in situ with high spatial resolution. Herein, we have incorporated terminally functionalized aggregation-induced emission active tetraphenylethene derivative and photochromic spiropyran moieties into the networks of liquid crystal elastomers through covalent bonding to obtain the synergistic photochromic luminescence and programmable soft actuators. Bio-mimic functions and light-induced auxetic metamaterial-like devices were shown to be feasible based on the combination of assembly and origami-programming strategy. These bioinspired devices with synergistic photochromic luminescence and complex photodeformation abilities provide an elegant strategy to design multi-functional liquid crystal actuators.

3.
Chem Commun (Camb) ; 57(7): 911-914, 2021 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-33393549

RESUMO

In recent years, graphdiyne and its derivatives with fascinating electro-optic properties have attracted tremendous scientific attention. Here we design and synthesize a graphdiyne-derived discotic liquid crystal material by decorating six wedge-shaped 3,4,5-tris(dodecyloxy)benzoate groups on the fundamental structural unit of graphdiyne, the dehydrotribenzo[18]annulene core. This graphdiyne-derived liquid crystal material exhibits a cubic phase and a hexagonal columnar phase at varied temperatures. Most interestingly, this molecule displays a tunable phase-dependent photoluminescence behavior. Under the irradiation of 365 nm wavelength ultraviolet light, the luminescent material emits pale blue, green and azure light in the cubic, hexagonal columnar and isotropic phases respectively. This graphdiyne-derived discotic liquid crystal with excellent optical characteristics might have application potentials in organic optoelectronic functional materials and devices.

4.
Chem Commun (Camb) ; 56(55): 7597-7600, 2020 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-32514511

RESUMO

A snake-mimic soft actuator composed of a bilayered liquid crystal elastomer ribbon and two serrated feet is reported in this work. Under repeated on/off near-infrared light irradiation, this actuator can move forward relying on a reversible shape morphing between S-curve structure and reverse S-curve structure, which is similar to the serpentine locomotion of snakes.

5.
Angew Chem Int Ed Engl ; 59(26): 10493-10497, 2020 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-32196893

RESUMO

Light-harvesting systems are an important way for capturing, transferring and utilizing light energy. It remains a key challenge to develop highly efficient artificial light-harvesting systems. Herein, we report a supramolecular co-assembly based on lower-rim dodecyl-modified sulfonatocalix[4]arene (SC4AD) and naphthyl-1,8-diphenyl pyridinium derivative (NPS) as a light-harvesting platform. NPS as a donor shows significant aggregation induced emission enhancement (AIEE) after assembling with SC4AD. Upon introduction of Nile blue (NiB) as an acceptor into the NPS-SC4AD co-assembly, the light-harvesting system becomes near-infrared (NIR) emissive (675 nm). Importantly, the NIR emitting NPS-SC4AD-NiB system exhibits an ultrahigh antenna effect (33.1) at a high donor/acceptor ratio (250:1). By co-staining PC-3 cells with a Golgi staining reagent, NBD C6 -ceramide, NIR imaging in the Golgi apparatus has been demonstrated using these NIR emissive nanoparticles.


Assuntos
Calixarenos/química , Corantes Fluorescentes/química , Complexo de Golgi/metabolismo , Compostos de Piridínio/química , Calixarenos/efeitos da radiação , Calixarenos/toxicidade , Transferência Ressonante de Energia de Fluorescência , Corantes Fluorescentes/efeitos da radiação , Corantes Fluorescentes/toxicidade , Humanos , Raios Infravermelhos , Microscopia Confocal , Microscopia de Fluorescência , Nanopartículas/química , Nanopartículas/efeitos da radiação , Nanopartículas/toxicidade , Oxazinas/química , Oxazinas/efeitos da radiação , Oxazinas/toxicidade , Células PC-3 , Compostos de Piridínio/efeitos da radiação , Compostos de Piridínio/toxicidade
6.
J Am Chem Soc ; 141(36): 14364-14369, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31429282

RESUMO

Liquid-crystal elastomer (LCE) materials, which have been developed and investigated for 4 decades, still lack real industrial applications. The fundamental obstacle is the modest force of LCEs generated in the LC-to-isotropic phase transition process, which is the most important actuation moment. Here, we report an interpenetrating liquid-crystal polyurethane/polyacrylate elastomer material, consisting of one main-chain polyurethane LCE and another liquid-crystal polyacrylate thermoset network, which are simultaneously polymerized. This two-way shape memory material can reversibly shrink/expand under thermal stimulus and show ultrastrong actuation-mechanics properties. With a maximum shrinkage ratio of 86% at 140 °C, which is beyond the LC-to-isotropic phase transition, its actuation blocking stress, actuation work capacity, breaking strength, and elastic modulus reach 2.53 MPa, 1267.7 kJ/m3, 7.9 MPa, and 10.4 MPa, respectively. Such LCE material can lift up a load 30 000 times heavier than its own weight. We hope the outstanding mechanical properties of this interpenetrating polymer network-LCE material would pave the way for real industrial utilizations of LCE-based soft actuators.

7.
Soft Matter ; 15(1): 73-77, 2018 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-30520497

RESUMO

Supramolecular hydrogels, which are usually used to develop excellent smart soft materials, are widely applied in miscellaneous fields due to their inherent reversible properties, unique functions and mechanical properties. Compared with covalently linked hydrogels, supramolecular hydrogels have advantages of easy preparation, stimulus responsiveness and good biocompatibility. Herein, after threading amino-modified ß-cyclodextrins onto poly(propyleneglycol)bis(2-amionopropylether) (PPG-NH2) chains, the resultant pseudorotaxanes non-covalently interacted with a clay nanosheet (CNS) matrix to construct supramolecular hydrogels bearing negative charges, and the mechanical properties of these hydrogels were positively correlated with the number of amino groups on the pseudorotaxane. Significantly, these hydrogels presented good adsorption properties for cationic dyes. The adsorption capacity (Qe) of the hydrogels towards rhodamine B (RhB), crystal violet (CV), and methylene blue (MB) could reach 181-228 mg g-1, and most of the dyes were adsorbed within 5 min. Thus, these hydrogels may have potential applications in the field of waste water treatment.

8.
Angew Chem Int Ed Engl ; 57(38): 12519-12523, 2018 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-30098089

RESUMO

A two-stage mediated near-infrared (NIR) emissive supramolecular assembly for lysosome-targeted cell imaging is presented. 4,4'-Anthracene-9,10-diylbis(ethene-2,1-diyl))bis(1-ethylpyridin-1-ium) bromide (ENDT) was synthesized as an organic dye with weak fluorescence emission at 625 nm. When ENDT complexes with cucurbit[8]uril (CB[8]), this binary supramolecular complex assembles into nanorods with a near-infrared fluorescence emission (655 nm) and fluorescence enhancement as the first stage. Such supramolecular complexes interact with lower-rim dodecyl-modified sulfonatocalix[4]arene (SC4AD) to form nanoparticles for further fluorescence enhancement as the second stage. Furthermore, based on a co-staining experiment with LysoTracker Blue, such nanoparticles can be applied in NIR lysosome-targeted cell imaging.


Assuntos
Hidrocarbonetos Aromáticos com Pontes/química , Calixarenos/química , Imidazóis/química , Lisossomos/metabolismo , Células A549 , Corantes Fluorescentes/química , Humanos , Microscopia Confocal , Nanopartículas/química , Piridinas/química , Espectroscopia de Luz Próxima ao Infravermelho
9.
ACS Appl Mater Interfaces ; 10(30): 24987-24992, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30010314

RESUMO

A kind of supramolecular assemblies was constructed from two water-soluble and biocompatible saccharides, sulfonato-ß-cyclodextrin (SCD) and chitosan, and characterized by dynamic light scattering (DLS), UV-vis, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The results showed that such nanoparticles presented good stability and controlled loading/release property, which enabled them as good drug carrier for berberine chloride (BE), a representative drug from traditional Chinese herbs. That is, the nanoparticles can load BE with high stability in a low-pH environment like that of the stomach but released BE when moved to a high-pH environment like that of the intestine.


Assuntos
Nanopartículas , Berberina , Quitosana , Preparações de Ação Retardada , Portadores de Fármacos , beta-Ciclodextrinas
10.
Macromol Rapid Commun ; 39(9): e1700869, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29527746

RESUMO

Circularly polarized luminescence (CPL) induced by host-guest complexation remains a challenge in supramolecular chemistry. Herein, a couple of CPL-silent enantiomeric guest binaphthylbis(4,4'-bipyridinium) salts can emit obvious CPL in the presence of cucurbit[8]uril in aqueous media, due to the restriction of molecular rotation limitation effect. Such CPL can be reversibly adjusted by the addition of acid and base. Furthermore, the resultant supramolecular systems can interact with DNA, accompanied by the morphological conversion from branched supramolecular nanowires to exfoliated nanowires, which can enable to the exploration of such supramolecular systems as DNA markers by CPL signals.


Assuntos
Hidrocarbonetos Aromáticos com Pontes/química , Imidazóis/química , Medições Luminescentes , Piridinas/química , Dicroísmo Circular , Luminescência , Estereoisomerismo
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