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1.
    
Long blood circulation in vivo remains a challenge to dual‐drug‐loaded nanocarriers for synergistic chemotherapy. Herein, a novel strategy to prepare lollipop‐like dual‐drug‐loaded nanoparticles (DOX–PDA–gossypol NPs) is developed based on the self‐assembly of gossypol, doxorubicin (DOX), and polydopamine (PDA) via π–π stacking. Dopamine polymerizes to PDA and fills the gaps between the gossypol and DOX molecules to form the super compact long‐circulating nanoparticles. The DOX–PDA–gossypol NPs show a suitable particle size of 59.6 ± 9.6 nm, high drug loading of 91%, superb stability, high maximum‐tolerated dose (MTD) of over 60 mg kg‐1, and negligible toxicity. These NPs also exhibit pH‐dependent drug release and low combination index (0.23). Notably, they show dramatically ultralong blood circulation (>192 h) with elimination half times 458‐fold and 258‐fold longer than that of free DOX and free gossypol, respectively. These values are markedly higher than most of the reported results. Therefore, the DOX–PDA–gossypol NPs have a high tumor accumulation of 12% remaining on the 8th day postinjection. This characteristic contributes to the excellent tumor comprehensive synergistic therapeutic efficacy (TIR > 90%) with low administration dosage and is benefitted for widening the drug therapeutic window. Thus, the proposed strategy has remarkable potential for tumor synergistic therapy.  相似文献   

2.
    
Hierarchical assemblies of perylenetetracarboxylic diimide bridged silsesquioxane (PDBS) with controlled structure at multi‐length scale are studied using both experimental and computational methods. The organization process spans multi‐length scales and includes three continuous steps: 1) stacking of the preprogrammed molecules into small clusters, 2) growing of the small clusters into nanoscale building blocks with various sizes and shapes depending on the experimental conditions, and 3) aggregation of nanoscale building blocks into micro‐ or macro‐scale assemblies. The main factors determining the assembly morphology are the second and third steps, which can be controlled by varying the experimental conditions, such as solution drying rate, solvent composition, and PDBS concentration. Despite the different morphologies, all of these assemblies possess highly ordered lamellar structure. It is found that incorporating perylenetetracarboxylic diimide (PD) moieties into the highly ordered silica network endows the PD components with high thermal and mechanical stability, as well as improved optical and electronic properties.  相似文献   

3.
    
Poly(3,4‐ethylenedioxythiophene):poly(4‐styrenesulfonate) (PEDOT:PSS) nanoparticles, after being coated with polyethylene glycol (PEG), are used as a drug carrier to load various types of aromatic therapeutic molecules, including chemotherapy drugs doxorubicin (DOX) and SN38, as well as a photodynamic agent chlorin e6 (Ce6), through π–π stacking and hydrophobic interaction. Interesting functionalities of PEDOT:PSS‐PEG as an unique versatile drug delivery platform are discovered. Firstly, for water‐insoluble drugs such as SN38, the loading on PEDOT:PSS‐PEG dramatically enhances its water solubility, while maintaining its cytotoxicity to cancer cells. Secondly, the delivery of Ce6 by PEDOT:PSS‐PEG is able to remarkably accelerate the cellular uptake of Ce6 molecules, and thus offers improved photodynamic therapeutic efficacy. Using DOX‐loaded PEDOT:PSS‐PEG as the model system, it is demonstrated that the photothermal effect of PEDOT:PSS‐PEG can be utilized to promote the delivery of this chemotherapeutic agent, achieving a combined photothermal‐ and chemotherapy with an obvious synergistic cancer killing effect. Moreover, it is also shown that multiple types of therapeutic agents could be simultaneously loaded on PEDOT:PSS‐PEG nanoparticles and delivered into cancer cells. This work highlights the great potential of NIR‐absorbing polymeric nanoparticles as multifunctional drug carriers for potential cancer combination therapy with high efficacy.  相似文献   

4.
    
The multidrug resistance (MDR) of cancer cells is a major obstacle in cancer chemotherapy and very few strategies are available to overcome it. Here, a new strategy is developed to codeliver a π–π stacked dual anticancer drug combination with an actively targeted, pH‐ and reduction‐sensitive polymer micellar platform for combating multidrug resistance and tumor metastasis. In contrast to other methods, two traditional chemotherapeutics, doxorubicin (DOX) and 10‐hydroxycamptothecin with complex aromatic π–π conjugated structures, are integrated into one drug delivery system via a π–π stacking interaction, which enables the released drugs to evade the recognition of drug pumps due to a slight change in the drug's molecular structure. The micelles exhibit active targeting of DOX‐resistant human breast cancer MCF‐7 cells (MCF‐7/ADR) and have the ability to control the release of the drug in response to the microenvironmental stimuli of tumor cells. As a result, the codelivery of the π–π stacked dual anticancer drug combination displays high therapeutic efficacy in the MCF‐7/ADR tumor model and successfully prevents the lung metastasis of tumor cells. The mechanism underlying the reversal of MDR is investigated, and the results reveal that the synergistic effect of the π–π stacked dual drugs promotes mitochondria‐dependent apoptosis.  相似文献   

5.
    
In this work, a joint experimental and computational study on the synthesis, self‐assembly, and ionic conduction characteristics of a new conjugated liquid crystal quaterthiophene/poly(ethylene oxide) (PEO4) consisting of terminal tetraethyleneglycol monomethyl ether groups on both ends of a quaterthiophene core is performed. In agreement with molecular dynamic simulations, temperature‐dependent grazing‐incidence wide angle X‐ray scattering and X‐ray diffraction indicate that the molecule spontaneously forms a smectic phase at ambient temperature as characterized both in bulk and thin film configurations. Significantly, this smectic phase is maintained upon blending with bis(trifluoro‐methanesulfonyl)imide as ion source at a concentration ratio up to r = [Li+]/[EO] = 0.05. Nanosegregation between oligothiophene and PEO moieties and π–π stacking of thiophene rings lead to the formation of efficient 2D pathways for ion transport, resulting in thin‐film in‐plane ionic conductivity as high as 5.2 × 10?4 S cm?1 at 70 °C and r = 0.05 as measured by electrochemical impedance spectroscopy. Upon heating the samples above a transition temperature around 95 °C, an isotropic phase forms associated with a pronounced drop in ionic conductivity. Upon cooling, partial and local reordering of the conducting smectic domains leads to an ionic conductivity decrease compared to the as‐cast state.  相似文献   

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Recently, polymer field‐effect transistors have gone through rapid development. Nevertheless, charge transport mechanism and structure‐property relationship are less understood. Here we use strong electron‐deficient benzodifurandione‐based poly(p‐phenylene vinylene) ( BDPPV ) as polymer backbone and develop six BDPPV ‐based polymers ( BDPPV‐C1 to C6 ) with various side‐chain branching positions to systematically study the side‐chain effect on device performance. All the polymers exhibited ambient‐stable n‐type transporting behaviors with the highest electron mobility of up to 1.40 cm2 V?1 s?1. The film morphologies and microstructures of all the six polymers were systematically investigated. Our results demonstrate that the interchain π–π stacking distance decreases as moving the branching position away from polymer backbones, and an unprecedentedly close π–π stacking distance down to 3.38 Å is obtained for BDPPV‐C4 to C6 . Nonetheless, closer π–π stacking distance does not always correlate with higher electron mobility. Polymer crystallinity, thin film disorder, and polymer packing conformation, which all influenced by side‐chain branching position, are proved to show significant influence on device performance. Our study not only reveals that π–π stacking distance is not the decisive factor on carrier mobility in conjugated polymers but also demonstrates that side‐chain branching position engineering is a powerful strategy to modulate and balance these factors in conjugated polymers.  相似文献   

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Commonly, one stimulus only induces one luminescence switching in stimuli‐responsive experiment. Herein, it is reported that one stimulus in situ induces two luminescent switches, resulting from two phase transitions in a solvent‐fuming process. Two phase transitions are in situ composed of a first fast and a subsequent slow process, corresponding to the change of molecular packing from the amorphous state to the π–π dimer crystalline state to the cocrystalline state with the inclusion of solvents, accompanied with luminescent transformation from pure blue to green to deep blue. Theoretical and experimental results reveal that the staggered π–π dimer stacking of anthracenes serves as the intermediate state to bridge the two phase transitions. This finding expands a new horizon in the stimuli‐responsive field and inspires novel applications in information storage and security fields.  相似文献   

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10.
    
Photodynamic therapy (PDT) mediated by near‐infrared (NIR) dyes is a promising cancer treatment modality; however, its use is limited by significant challenges, such as hypoxic tumor microenvironments and self‐quenching of photosensitizers. These challenges hamper its utility in inducing immunogenic cell death (ICD) and triggering potent systemic antitumor immune responses. This study demonstrates that molecular dispersion of NIR dyes in nanocarriers can significantly enhance their ability to produce reactive oxygen species and potentiate synergistic PDT and photothermal therapy against tumors. Specifically, NIR dye indocyanine green (ICG) can be spontaneously adsorbed to covalent organic frameworks (COFs) via π–π conjugations to prevent intermolecular stacking interactions. Then, ICG‐loaded COFs are ultrasonically exfoliated and coated with polydopamine (PDA) to construct a new phototherapeutic agent ICG@COF‐1@PDA with enhanced efficacy. In conjunction with ICG@COF‐1@PDA, a single round of NIR laser irradiation can induce obvious ICD, elicit antitumor immunity in colorectal cancer, and yield 62.9% inhibition of untreated distant tumors. ICG@COF‐1@PDA also exhibits notable phototherapeutic efficacy against 4T1 murine breast to lung metastasis, a spontaneous metastasis mode for triple‐negative breast cancers (TNBCs). Overall, this study reveals a novel nanodelivery system for molecular dispersion of NIR dyes, which may present new therapeutic opportunities against primary and metastatic tumors.  相似文献   

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Under first‐principles computations, a simple strategy is identified to modulate the electronic and magnetic properties of zigzag graphene nanoribbons (zGNRs). This strategy takes advantage of the effect of the floating dipole field attached to zGNRs via π–π interactions. This dipole field is induced by the acceptor/donor functional groups, which decorate the ladder‐structure polydiacetylene derivatives with an excellent delocalized π‐conjugated backbone. By tuning the acceptor/donor groups, –C≡C– number, and zGNR width, greatly enriched electronic and magnetic properties, e.g., spin gapless semiconducting, half‐metallic, and metallic behaviors, with the antiferromagnetic?ferromagnetic conversion can be achieved in zGNRs with perfect, 57‐reconstructed, and partially hydrogenated edge patterns.  相似文献   

13.
    
The properties of poly(alkylthiophenes) in solution are found to have a profound impact on the self assembly process and thus the microstructural and electrical properties of the resultant thin films. Ordered supramolecular precursors can be formed in regioregular poly(3‐hexylthiophene) (P3HT) solutions through the application of low intensity ultrasound. These precursors survive the casting process, resulting in a dramatic increase in the degree of crystallinity of the thin films obtained by spin coating. The crystallinity of the films is tunable, with a continuous evolution of mesoscale structures observed as a function of ultrasonic irradiation time. The photophysical properties of P3HT in solution as well in the solid state suggest that the application of ultrasound leads to a π stacking induced molecular aggregation resulting in field effect mobilities as high as 0.03 cm2 V?1 s?1. A multiphase morphology, comprising short quasi‐ordered and larger, ordered nanofibrils embedded in a disordered amorphous phase is formed as a result of irradiation for at least 1 min. Two distinct regions of charge transport are identified, characterized by an initial sharp increase in the field effect mobility by two orders of magnitude due to an increase in crystallinity up to the percolation limit, followed by a gradual saturation where the mobility becomes independent of the thin film microstructure.  相似文献   

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15.
    
The discovery of nanodipolar π‐conjugated oligomer‐containing polymers as high performance nanodielectric materials with high permittivity and low dielectric loss over a wide range of frequency (100 Hz–4 MHz) is reported. Terthiophene‐containing methacrylate polymers are synthesized by reversible addition fragmentation transfer (RAFT) polymerization. Both X‐ray and thermal studies indicate the formation of small crystalline domains of terthiophene side chains dispersed in amorphous matrix. The highly polarizable and fast‐responsive nanodipoles from the nanoscale crystalline domains (<2 nm) are believed to dictate the performance. These polymers uniquely satisfy nanodipole architectures conjectured two decades ago to guide the design of high performance nanodielectric materials. This unprecedented approach can be generalized to a variety of π‐conjugated oligomer‐containing polymers for the development of high energy density capacitor materials.  相似文献   

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17.
    
Sequence‐independent or “click”‐type chemistry is applied for the preparation of novel π‐conjugated oligomers. A variety of bi‐functional monomers for Wittig–Horner olefination are developed and applied in a sequential protection–deprotection process for the preparation of structurally similar π‐conjugated oligomers. Selected oligomers are incorporated as the organic semiconductors in light‐emitting diodes and a field‐effect transistor, demonstrating the potential of the approach.  相似文献   

18.
    
A series of semiconducting small molecules with bithiophene or bis‐3,4‐ethylenedioxythiophene cores are designed and synthesized. The molecules display stable reversible oxidation in solution and can be reversibly oxidized in the solid state with aqueous electrolyte when functionalized with polar triethylene glycol side chains. Evidence of promising ion injection properties observed with cyclic voltammetry is complemented by strong electrochromism probed by spectroelectrochemistry. Blending these molecules with high molecular weight polyethylene oxide (PEO) is found to improve both ion injection and thin film stability. The molecules and their corresponding PEO blends are investigated as active layers in organic electrochemical transistors (OECTs). For the most promising molecule:polymer blend (P4E4:PEO), p‐type accumulation mode OECTs with µA drain currents, μS peak transconductances, and a µC* figure‐of‐merit value of 0.81 F V−1 cm−1 s−1 are obtained.  相似文献   

19.
    
Liquid‐infused coatings are because of their fluidity of considerable technological importance for hydrophobic materials with multifunctional properties, such as self‐healing, transmittance, and durability. However, conventional coatings absorb viscous liquid into their sponge‐like structured surface, causing uncontrollable liquid layer formation or liquid transport. In addition, a hydrophobic‐liquid‐retained surface can cause instability and lead to limitation of the hydrophobicity, optical properties, and flexibility due to liquid layer evaporation. Here, we report a strategy for controllable liquid‐layer formation on smooth surfaces (R rms < 1 nm) by π ‐electron interactions. Using this technology, superoleophilic wetting of decyltrimethoxysilane results in the design of a surface with π ‐interaction liquid adsorption, smoothness, and hydrophobicity (SPLASH), that shows extraordinary hydrophobicity (CAH = 0.75°), and stable repellence for various water‐based solutions including micrometer‐sized mist. The smoothness of the solid under a liquid layer enabled the SPLASH to exhibit stable hydrophobicity, transparency (>90%), structure damage durability and flexibility, regardless of the liquid layer thickness by bending or evaporation. Furthermore, the patterned π ‐electrons' localization on the smooth coating enables controlled liquid‐layer formation and liquid transport. This strategy may provide new insights into designing functional liquid surfaces and our designed surface with multifunctional properties could be developed for various applications.  相似文献   

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