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1.
J Phys Chem Lett ; 15(15): 4015-4023, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38577843

RESUMO

Wide-bandgap (WBG) perovskites play a crucial role in perovskite-based tandem cells. Despite recent advances using self-assembled monolayers (SAMs) to facilitate efficiency breakthroughs, achieving precise control over the deposition of such ultrathin layers remains a significant challenge for large-scale fabrication of WBG perovskite and, consequently, for the tandem modules. To address these challenges, we propose a facile method that integrates MeO-2PACz and Me-4PACz in optimal proportions (Mixed SAMs) into the perovskite precursor solution, enabling the simultaneous codeposition of WBG perovskite and SAMs. This technique promotes the spontaneous formation of charge-selective contacts while reducing defect densities by coordinating phosphonic acid groups with the unbonded Pb2+ ions at the bottom interface. The resulting WBG perovskite solar cells (PSCs) demonstrated a power conversion efficiency of 19.31% for small-area devices (0.0585 cm2) and 17.63% for large-area modules (19.34 cm2), highlighting the potential of this codeposition strategy for fabricating high-performance, large-area WBG PSCs with enhanced reproducibility. These findings offer valuable insights for advancing WBG PSCs and the scalable fabrication of modules.

2.
Sci Total Environ ; 919: 170494, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38342449

RESUMO

Heavy metal migration behaviors and mechanisms in soils are important for pollution control and remediation. However, there are few related studies in arid areas under extreme weather patterns. In this study, we developed a one-dimensional continuous point source unsaturated solute transport model, and utilized Hydrus-1D to simulate the transport of Cu, As and Zn, in the pack gas zones of soils within the impact areas of two typical mining areas in Inner Mongolia. The results show that the soil has a significant interception capacity, with a short heavy metal vertical migration distance of ≤100 cm. Soil texture and heavy metal sorption affinity are two key factors that influence heavy metal transport. In soils with high contents of sands but low contents of clays, heavy metals have large mobility and thus migrate deeper and are more evenly distributed in the soil profile. The migration of different heavy metals in the same soil also varies considerably, with large migration depth for metals having low binding affinities onto soils. Scenario analysis for extreme drought and rainfall shows that, rainfall amount and intensity are positively correlated with heavy metal transport depth and negatively correlated with the peak concentration. Increasing rainfall/intensity results in a more uniform distribution of heavy metals, and lower profile concentrations owing to enhanced horizontal dispersion of surface runoff. When the total amount and intensity of rainfall remain constant, continuous or intermittent rainfall only affects the transport process but has almost no effect on the final pollutant concentration redistribution in the soil. These results provide theoretical data for estimating the degree of heavy metal pollution, and help design control and remediation strategies for polluted soils.

3.
Sci Total Environ ; 919: 170904, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38354799

RESUMO

Using cucumber, maize, and ryegrass as model plants, the diversity and uniqueness of the molecular compositions of dissolved organic matter (DOM) and the structures of microbial communities in typical crop rhizosphere soils, as well as their associations, were investigated based on high-resolution mass spectrometry combined with high-throughput sequencing. The results showed that the rhizosphere contained 2200 organic molecules that were not identified in the non-rhizosphere soils, as characterized by FT-ICR-MS. The rhizosphere DOM molecules generally contained more N, S, and P heteroatoms, stronger hydrophilicity, and more refractory organic matter, representing high and complex chemical diversity characteristics. 16SrRNA sequencing results demonstrated that Proteobacteria, Actinomycetes and Firmicutes were the dominant flora in the soils. Plant species could significantly change the composition and relative abundance of rhizosphere microbial populations. The microbial community structures of rhizosphere and non-rhizosphere soils showed significant differences at both the phylum and class levels. Multiple interactions between the microorganisms and DOM compositions formed a complex network of relationships. There were strong and remarkable positive or negative couplings between different sizes and categories of DOM molecules and the specific microbial groups (P < 0.05, |R| ≥ 0.9) in the rhizosphere soils as shown by network profiles. The correlations between DOM molecules and microbial groups in rhizosphere soils had plant species specificity. The results above emphasized the relationship between the heterogeneity of DOM and the diversity of microbial communities, and explored the molecular mechanisms of the biochemical associations in typical plant rhizosphere soils, providing a foundation for in-depth understanding of plant-soil-microbe interactions.


Assuntos
Microbiota , Solo , Solo/química , Matéria Orgânica Dissolvida , Rizosfera , Microbiota/genética , Sequenciamento de Nucleotídeos em Larga Escala , Microbiologia do Solo
4.
Nat Commun ; 14(1): 4961, 2023 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-37587158

RESUMO

Metal halide perovskites are promising for next-generation flexible photodetectors owing to their low-temperature solution processability, mechanical flexibility, and excellent photoelectric properties. However, the defects and notorious ion migration in polycrystalline metal halide perovskites often lead to high and unstable dark current, thus deteriorating their detection limit and long-term operations. Here, we propose an electrical field modulation strategy to significantly reduce the dark current of metal halide perovskites-based flexible photodetector more than 1000 times (from ~5 nA to ~5 pA). Meanwhile, ion migration in metal halide perovskites is effectively suppressed, and the metal halide perovskites-based flexible photodetector shows a long-term continuous operational stability (~8000 s) with low signal drift (~4.2 × 10-4 pA per second) and ultralow dark current drift (~1.3 × 10-5 pA per second). Benefitting from the electrical modulation strategy, a high signal-to-noise ratio wearable photoplethysmography sensor and an active-matrix photodetector array for weak light imaging are successfully demonstrated. This work offers a universal strategy to improve the performance of metal halide perovskites for wearable flexible photodetector and image sensor applications.

5.
Environ Sci Pollut Res Int ; 30(34): 82770-82779, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37335514

RESUMO

Tetrabromobisphenol A (TBBPA) is the most abundant brominated flame retardant and bisphenol A (BPA) is often identified as the metabolic product of TBBPA. Both of them are highly bioconcentrated and show serious biological toxicity. In this study, an analytical method was optimized to simultaneously determine TBBPA and BPA in plant samples. Moreover, the uptake and metabolism of TBBPA in maize were investigated through hydroponic exposure experiment. The whole analysis procedure included ultrasonic extraction, lipid removal, purification by solid-phase extraction cartridge, derivatization, and detection by GC/MS. Optimizations were conducted for each pretreatment step above. After improvement, methyl tert-butyl ether (MTBE) was chosen as the extraction solvent; the lipid removal was conducted by repartition between organic solvent and alkaline solution. The best suitable pH condition is 2-2.5 for the inorganic solvent before used for further purification by HLB and silica column with the optimized elute solvent of acetone and mixtures of acetone and hexane (1:1), respectively. The recoveries of TBBPA and BPA spiked in maize samples were 69±4% and 66±4% with the relative standard deviation less than 5%, respectively, for the entire treatment procedure. Limits of detections were 4.10 ng/g and 0.13 ng/g for TBBPA and BPA in plant samples, respectively. In the hydroponic exposure experiment (100 µg/L, 15 d), the concentrations of TBBPA in maize cultivated in pH 5.8 and pH 7.0 Hoagland solutions were 1.45 and 0.89 µg/g in roots and 8.45 and 6.34 ng/g in stems, while they were all below the detection limit for leaves, respectively. The distribution of TBBPA in different tissues was as the following order: root>>stem>leaf, illustrating the accumulation in the root and the translocation to the stem. The uptake variations under different pH conditions were attributed to the change of TBBPA species, now that it shows greater hydrophobicity at lower pH condition as a kind of ionic organic contaminant. Monobromobisphenol A and dibromobisphenol A were identified as metabolisms products of TBBPA in maize. The efficiency and simplicity of the method that we proposed characterize its potential application as a screening tool for environmental monitoring and contribute to a comprehensive study of the environmental behavior of TBBPA.


Assuntos
Retardadores de Chama , Bifenil Polibromatos , Acetona , Bifenil Polibromatos/química , Solventes , Retardadores de Chama/análise , Lipídeos
6.
J Am Chem Soc ; 145(20): 11227-11235, 2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37159928

RESUMO

Whether and how an electron-hole pair at the donor-acceptor interface separates from their mutual Coulombic interaction has been a long-standing question for both fundamental interests and optoelectronic applications. This question is particularly interesting but yet to be unraveled in the emerging mixed-dimensional organic/2D semiconductor excitonic heterostructures where the Coulomb interaction is poorly screened. Here, by tracking the characteristic electroabsorption (Stark effect) signal from separated charges using transient absorption spectroscopy, we directly follow the electron-hole pair separation process in a model organic/2D heterostructure, vanadium oxide phthalocyanine/monolayer MoS2. After sub-100 fs photoinduced interfacial electron transfer, we observe a barrier-less long-range electron-hole pair separation to free carriers within 1 ps by hot charge transfer exciton dissociation. Further experiment reveals the key role of the charge delocalization in organic layers sustained by the local crystallinity, while the inherent in-plane delocalization of the 2D semiconductor has a negligible contribution to charge pair separation. This study reconciles the seemingly contradicting charge transfer exciton emission and dissociation process and is important to the future development of efficient organic/2D semiconductor optoelectronic devices.

7.
ACS Appl Mater Interfaces ; 15(18): 22752-22761, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37119204

RESUMO

Hole-transport materials (HTMs) play an important role in perovskite solar cells (PSCs) to enhance the power conversion efficiency (PCE). The innovation of HTMs can increase the hole extraction ability and reduce interfacial recombination. Three organic small molecule HTMs with 4H-cyclopenta[2,1-b:3,4-b']dithiophene (CPDT) as the central unit was designed and synthesized, namely, CPDTE-MTP (with the 2-ethylhexyl substituent and diphenylamine derivative end-group), CPDT-MTP (with the hexyl substituent and diphenylamine derivative end-group), and CPDT-PMTP (with the hexyl substituent and triphenylamine derivative end-group), which can form bifunctional and robust hole transport layer (HTL) on ITO and is tolerable to subsequent solvent and thermal processing. The X-ray photoelectron spectroscopy (XPS) results proved that CPDT-based HTMs can both interact with ITO through the nitrogen element in them and the tin element in ITO and passivate the upper perovskite layer. It is worth noting that the champion efficiency of MAPbI3 PSCs based on CPDT-PMTP achieved 20.77%, with an open circuit voltage (VOC) of 1.10 V, a short-circuit current (JSC) of 23.39 mA cm-2, and a fill factor (FF) of 80.83%, as three new materials were introduced into p-i-n PSCs as dopant-free HTMs.

8.
Adv Mater ; 35(29): e2208820, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36810905

RESUMO

Exploration of clinically acceptable blood glucose monitors has been engaging in the past decades, yet the ability to quantitatively detect blood glucose in a painless, accurate, and highly sensitive manner remains limited. Herein, a fluorescence-amplified origami microneedle (FAOM) device is described that integrates tubular DNA-origami nanostructures and glucose oxidase molecules into its inner network to quantitatively monitor blood glucose. The skin-attached FAOM device can collect glucose molecules in situ and transfer the input into a proton signal after the oxidase's catalysis. The proton-driven mechanical reconfiguration of DNA-origami tubes separates fluorescent molecules and their quenchers, eventually amplifying the glucose-correlated fluorescence signal. The function equation established on clinical examinees suggests that FAOM can report blood glucose in a highly sensitive and quantitative manner. In clinical blind tests, the FAOM achieves well-matched accuracy (98.70 ± 4.77%) compared with a commercial blood biochemical analyzer, fully meeting the requirements of accurate blood glucose monitoring. The FAOM device can be inserted into skin tissue in a trivially painful manner and with minimal leakage of DNA origami, substantially improving the tolerance and compliance of the blood glucose test.


Assuntos
Glicemia , Nanoestruturas , Conformação de Ácido Nucleico , Automonitorização da Glicemia , Prótons , DNA/química , Nanoestruturas/química , Glucose
9.
Sci Total Environ ; 855: 158934, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36152865

RESUMO

As a class of persistent organic pollutant, polybrominated diphenyl ethers (PBDEs) and their hydroxylated and methoxylated derivatives (OH-PBDEs and MeO-PBDEs) have been widely detected in soil environments. However, studies on the bioavailability and transformation of PBDEs and their derivatives in soil organisms remain scarce. In this study, a detailed kinetic investigation on the accumulation and biotransformations of BDE-47, 6-MeO-BDE-47 and 6-OH-BDE-47 in earthworms (Eisenia fetida) exposed to artificially contaminated soils was conducted. The uptake and elimination kinetics of BDE-47, 6-MeO-BDE-47 and 6-OH-BDE-47 by earthworms were in accordance with a one-compartment first-order kinetic model. The bioaccumulation factors (BAFs) followed the order 6-MeO-BDE-47 > 6-OH-BDE-47 > BDE-47. All three compounds could undergo step-by-step debromination to produce lower brominated analogs in earthworms. Both BDE-47 and 6-OH-BDE-47 could be transformed to MeO-PBDEs, whereas no transformation from 6-OH-BDE-47 or 6-MeO-BDE-47 to PBDEs or from BDE-47 and 6-MeO-BDE-47 to OH-PBDEs took place in the earthworms. Methoxylation was proposed as a potential metabolic pathway to form MeO-PBDEs in earthworms, with the metabolic rates for the methoxylation of BDE-47 and 6-OH-BDE-47 being 27.7 and 5.1 times greater, respectively, than that of the debromination metabolism. The isomers of 6-MeO-BDE-47 and 6-OH-BDE-47 were formed via the addition of methoxy/hydroxy groups or via bromine shifts on benzene ring in the earthworms. This study provides comprehensive information for a better understanding of the accumulation and biotransformation of PBDEs and their derivatives in earthworms.


Assuntos
Éteres Difenil Halogenados , Oligoquetos , Animais , Éteres Difenil Halogenados/análise , Oligoquetos/metabolismo , Éter , Hidroxilação , Biotransformação , Etil-Éteres , Solo
10.
Sci Adv ; 8(43): eabq4935, 2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36288313

RESUMO

Upconverting infrared light into visible light via the triplet-triplet annihilation process in solid state is important for various applications including photovoltaics, photodetection, and bioimaging. Although inorganic semiconductors with broad absorption and negligible exchange energy loss have emerged as promising alternative to molecular sensitizers, currently, they have exclusively suffered from low efficiency and contained toxic elements in near-infrared (NIR)-to-visible upconversion. Here, we report an ultrathin bilayer film for NIR-to-visible upconversion based on atomically thin two-dimensional (2D) monolayer semiconductors. The atomic flatness and strong light absorption of 2D monolayer semiconductors enable ultrafast energy transfer and robust NIR-to-visible emission with a high upconversion quantum yield (1.1 ± 0.2%) at modest incident power (260 mW cm-2). Increasing layer thickness adversely quenches the upconversion emission, highlighting the 2D advantage. Considering the whole library of 2D semiconductors, the facile large-scale production and the ultrathin solid-state architecture open a new research field for solid-state upconversion applications.

11.
Adv Mater ; 34(42): e2205458, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35963008

RESUMO

Conventional energy-integration black-white X-ray imaging lacks the spectral information of X-ray photons. Although X-ray spectra (energy) can be distinguished by the photon-counting technique typically with CdZnTe detectors, it is very challenging to be applied to large-area flat-panel X-ray imaging (FPXI). Herein, multilayer stacked scintillators of different X-ray absorption capabilities and scintillation spectra are designed; in this scenario, the X-ray energy can be discriminated by detecting the emission spectra of each scintillator; therefore, multispectral X-ray imaging can be easily obtained by color or multispectral visible-light camera in a single shot of X-rays. To verify this idea, stacked multilayer scintillators based on several emerging metal halides are fabricated in a cost-effective and scalable solution process, and proof-of-concept multispectral (or multi-energy) FPXI are experimentally demonstrated. The dual-energy X-ray image of a "bone-muscle" model clearly shows the details that are invisible in conventional energy-integration FPXI. By stacking four layers of specifically designed multilayer scintillators with appropriate thicknesses, a prototype FPXI with four energy channels is realized, proving its extendibility to multispectral or even hyperspectral X-ray imaging. This study provides a facile and effective strategy to realize multispectral large-area flat-panel X-ray imaging.

12.
ACS Nano ; 16(8): 12532-12540, 2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-35900068

RESUMO

Hybrid heterostructures (HSs) comprising organic and two-dimensional (2D) monolayer semiconductors hold great promise for optoelectronic applications. So far, research efforts on organic/2D HSs have exclusively focused on coupling directly photoexcited singlets to monolayer semiconductors. It remains unexplored whether and how the optically dark triplets in organic semiconductors with intriguing properties (e.g., long lifetime) can be implemented for modulating light-matter interactions of hybrid HSs. Herein, we investigate the triplet sensitization of monolayer semiconductors by time-resolved spectroscopic studies on Pd-octaethylporphyrin (PdOEP)/WSe2 and PdOEP/WS2 HSs with type I and type II band alignment, respectively. We show that PdOEP triplets formed in ∼5 ps from intersystem crossing can transfer energy or charge to WSe2 or WS2 monolayers, respectively, leading to a significant photoluminescence enhancement (180%) in WSe2 or long-lived charge separation (>2 ns) in WS2. The triplet transfer occurs in ∼100 ns, which is more than 3 orders of magnitude slower than singlet and can be attributed to its tightly localized nature. Further study of thickness dependence reveals the dictating role of triplet diffusion for triplet sensitization in organic/2D HSs. This study shows the great promise of much less explored molecular triplets on sensitizing 2D monolayer semiconductors and provides the guidance to achieve long-range light harvesting and energy migration in organic/2D HSs for enhanced optoelectronic applications.

13.
Small Methods ; 6(8): e2200500, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35754169

RESUMO

Lead halide perovskites possess heavy elements and excellent mobility-lifetime (µτ) product, becoming desirable candidates for X-ray detectors. However, current perovskite photoconduction detectors (PCDs) with vertical geometry, where electronic signals and mobile ions share the same conduction path, are facing with extremely challenging ion-migration issue. Herein, a hybrid X-ray detector device structure, in which perovskite is vertically stacked onto an indium oxide (In2 O3 ) transistor with lateral transport geometry is designed, perovskite mainly acts as X-ray sensitizer to activate In2 O3 conduction channel, the actual electrical signal is conducted and collected in the lateral metal-oxide device. With the decoupled ionic and electronic transportation, hybrid detectors are insensitive to the ionic motion of perovskite, hence demonstrating no hysteresis and almost no shifting of baseline that are often observed in PCDs, hybrid detectors also exhibit reduced dark current, improved response time, and four times higher photocurrent signals. Finally, array integration of hybrid detectors and preliminary X-ray imaging is realized. The work provides an effective device strategy in addition to the mere material alternations to attain high-performance perovskite-based X-ray detectors and arrays.

14.
Small Methods ; 6(5): e2200048, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35266331

RESUMO

The traditional way to stabilize α-phase formamidinium lead triiodide (FAPbI3 ) perovskite often involves considerable additions of methylammonium (MA) and bromide into the perovskite lattice, leading to an enlarged bandgap and reduced thermal stability. This work shows a seed-assisted growth strategy to induce a bottom-up crystallization of MA-free perovskite, by introducing a small amount of α-CsPbBr3 /DMSO (5%) as seeds into the pristine FAPbI3 system. During the initial crystalization period, the typical hexagonal α-FAPbI3 crystals (containing α-CsPbBr3 seeds) are directly formed even at ambient temperature, as observed by laser scanning confocal microscopy. It indicates that these seeds can promote the formation and stabilization of α-FAPbI3 below the thermodynamic phase-transition temperature. After annealing not beyond 100 °C, CsPbBr3 seeds homogeneously diffused into the entire perovskite layer via an ions exchange process. This work demonstrates an efficiency of 22% with hysteresis-free inverted perovskite solar cells (PSCs), one of the highest performances for MA-free inverted PSCs. Despite absented passivation processes, open-circuit voltage is improved by 100 millivolts compared to the control devices with the same stoichiometry, and long-term operational stability retained 92% under continuous full sun illumination. Going MA-free and low-temperature processes are a new insight for compatibility with tandems or flexible PSCs.

15.
Chemistry ; 27(55): 13828-13839, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34291514

RESUMO

Achieving high efficiency at high luminance is one of the most important prerequisites towards practical application of any kind of light-emitting diode (LED). Herein, we report highly emissive organic fluorescent molecules based on phenanthroimidazole-benzothiadiazole derivatives capable of maintaining high external quantum efficiency (EQE) at high luminance enabled by triplet-triplet fusion (TTF) in doped organic LEDs. The PIBzP-, PIBzPCN-, and PIBzTPA-based devices showed EQEs of 8.27, 9.15, and 8.64 %, respectively, at luminance of higher than 1000 cd m-2 , with little efficiency roll-off.

16.
J Phys Chem Lett ; 12(23): 5580-5586, 2021 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-34107680

RESUMO

The gas pumping method (GP) holds the potential of outperforming the antisolvent method (AS) for fabricating perovskite solar cells (PSCs) in many ways such as free of toxic solvents, improved film uniformity, and device reproducibility. Most of the highest power conversion efficiencies (PCEs) of PSCs are still achieved by AS. Successful demonstrations of inverted PSCs produced by GP as well as the corresponding mechanisms are still lacking. Herein, we fabricate highly efficient inverted PSCs by GP delivering an overall efficiency of 21.54%, on par with that of the devices by AS (21.41%), and a superior reproducibility at the optimal film thickness. Nevertheless, as the perovskite film thickness increases, the PCE of GP devices slightly dropped while the AS devices decreased significantly. We found that the AS method tends to produce horizontal grain boundaries due to the heterogeneous solvent extraction while they can be effectively suppresed by the GP method.

17.
Chem Asian J ; 16(14): 1942-1948, 2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34003594

RESUMO

Red emission is one of the three primary colors and is indispensable for full color displays. Fluorescent materials that can generate efficient red electroluminescence (EL) are limited and need to be developed. In this work, we report efficient red emitters based on phenanthro[9,10-d]imidazole-naphtho[2,3-c][1,2,5]thiadiazole donor-acceptor derivatives. The molecules, abbreviated as PINzP and PINzPCN, exhibited high photoluminescence quantum yield (PLQY) up to unity in doped films. They can also reach a relatively high PLQY of ∼30% in neat films. PINzP and PINzPCN were capable of generating efficient red EL in doped devices with a maximum external quantum efficiency (EQE) of 6.96% and 5.92%, respectively.

18.
RSC Adv ; 10(31): 18400-18406, 2020 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35517223

RESUMO

Inverted perovskite solar cells (PSCs) have recently gained increasing attention because of the long operation lifetime achieved. However, bathocuproine (BCP): a commonly used buffer layer in inverted PSCs, is experimentally confirmed by us to show fast aggregation at the temperature of 85 °C, which is the protocol temperature required by the International Electrotechnical Commission (IEC) standard. This thermal instability of the BCP interfacial layer makes long-term thermal stability of inverted PSCs questionable. Simply removing or replacing it can directly lead to an inferior PCE of a device. We solve this problem by removing the BCP layer and simultaneously increasing the thickness of C60, which obtains a high efficiency of 18% comparable with the device with BCP. This is possibly attributed to the extended migration path of carriers from C60 to metal electrode Ag, consequently reducing the carrier accumulation at the interface. In addition to the interfacial modification, the addition of ionic liquid: BMIMBF4 into perovskite can further improve a device's thermal stability by its effective suppression of perovskite decomposition. The devices with 0.4 mol% of BMIMBF4 exhibit promising thermal stability by retaining 80% of their initial PCE after thermal aging of 400 h at 85 °C.

19.
J Am Chem Soc ; 141(48): 19032-19037, 2019 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-31729871

RESUMO

Precisely assembled DNA nanostructures are promising candidates for the delivery of biomolecule-based therapeutics. Herein, we introduce a facile strategy for the construction of a branched DNA-based nanoplatform for codelivery of gene editing (sgRNA/Cas9, targeting DNA in the nucleus) and gene silencing (antisense, targeting mRNA in the cytoplasm) components for synergistic tumor therapy in vitro and in vivo. In our design, the branched DNA structure can efficiently load a sgRNA/Cas9/antisense complex targeting a tumor-associated gene, PLK1, through DNA self-assembly. With the incorporation of an active targeting aptamer and an endosomal escape peptide by host-guest interaction, the biocompatible DNA nanoplatform demonstrates efficient inhibition of tumor growth without apparent systemic toxicity. This multifunctional DNA nanocarrier provides a new strategy for the development of gene therapeutics.


Assuntos
Neoplasias da Mama/terapia , Sistemas CRISPR-Cas , DNA/química , Edição de Genes/métodos , RNA Antissenso/administração & dosagem , RNA Guia de Cinetoplastídeos/administração & dosagem , Animais , Neoplasias da Mama/genética , Proteínas de Ciclo Celular/genética , Feminino , Terapia Genética/métodos , Humanos , Células MCF-7 , Camundongos , Camundongos Endogâmicos BALB C , Nanoestruturas/química , Proteínas Serina-Treonina Quinases/genética , Proteínas Proto-Oncogênicas/genética , RNA Antissenso/genética , RNA Antissenso/uso terapêutico , RNA Guia de Cinetoplastídeos/genética , RNA Guia de Cinetoplastídeos/uso terapêutico , Quinase 1 Polo-Like
20.
J Am Chem Soc ; 141(24): 9490-9494, 2019 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-31184485

RESUMO

The exploration of biocompatible materials with circularly polarized luminescence (CPL) activity is becoming an attractive topic due to the great potential application in biosensing and bioimaging. Here, we describe a strategy to fabricate new CPL-active biomaterials using achiral carbazole-based biscyanine fluorophores coassembled with chiral deoxyribonucleic acid (DNA) molecules. This cyanine molecule has been shown to behave as a DNA detecting probe, featuring strong fluorescent emission induced by restriction of intramolecular rotation (RIR). When the achiral cyanine molecules are bound to the minor groove of DNA via electrostatic attraction in aqueous solution, the chirality of the DNA molecules can be transferred to the confined RIR cyanine dyes, triggering a remarkable circularly polarized luminescent emission. The chirality of the CPL signal can be regulated by the structures of the DNA templates. Stimuli-responsive CPL activates were observed from DNA-cyanine complexes. We further verified this strategy on different DNA-based nanomaterials, including DNA origami nanostructure. Our design presents a new avenue to fabricate compatible CPL materials.


Assuntos
Carbazóis/química , DNA/química , Corantes Fluorescentes/química , Compostos de Piridínio/química , Fluorescência , Nanocompostos/química , Espectrometria de Fluorescência
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