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1.
Org Lett ; 22(13): 5140-5144, 2020 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-32610929

RESUMO

An efficient and regioselective synthesis of fused polycyclic furo[3,4-c]indolo[2,1-a]isoquinolines through Rh(III)-catalyzed cascade C-H activation/annulation/lactonization of 2-arylindoles and 4-hydroxy-2-alkynoates has been developed. This cascade reaction displays high step economy and efficiency and tolerates various functional groups. The titled polycyclic furo[3,4-c]indolo[2,1-a]isoquinolines exhibit fluorescence emission.

2.
Artigo em Inglês | MEDLINE | ID: mdl-32608960

RESUMO

A novel surface-enhanced Raman scattering/surface plasmon resonance (SERS/SPR) dual-mode biosensor prepared on a silver nanorod-covered silver nanohole (Ag NR-NH) array by surface modification of tetrahedral DNA probes is proposed for highly sensitive detecting nucleic acids by a special signal amplification strategy of DNA supersandwich. The Ag NR-NH with a large area and uniformly arrayed nanostructure possesses excellent anisotropic extraordinary optical transmission and strong localized surface plasmon resonance, which lead to sensitive SPR response to the change of a local refractive index and strong localized electric fields for excellent SERS activity. To obtain high sensitivity and specificity, smart tetrahedral DNA probes are immobilized onto the Ag NR-NH array and the DNA supersandwich sensing strategy, including the signal amplification of DNA concatamers, is used. About 10 times signal enhancement for SPR and 4 times for SERS are achieved by this sensing strategy. In the detection of the target DNA in the human serum, the two sensing modes have complementary performances, i.e., the limit of detection for the SPR array is high (0.51 pM), while for SERS, it is low (0.77 fM), but the specificity for SPR is much higher than that of SERS. This improves the robustness of the DNA sensors, and subsequent recovery tests also confirm good reliability of the biosensor. The proposed SERS/SPR dual-mode biosensor has a great potential for high performance and reliable detection of trace disease-related nucleic acid biomarkers in the serum and is a powerful sensing platform for early-stage disease diagnosis.

3.
Chem Commun (Camb) ; 2020 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-32638751

RESUMO

The nanoprobe-based signal amplification strategy is a powerful way to ultrasensitively detect biomolecules. Herein, a gold nanoparticle-decorated molybdenum disulfide (MoS2-AuNP)-based multilayer nanoprobe (MLNP) was designed for ultrasensitive analysis of microRNA-21 (miRNA-21). The MLNP-amplified electrochemical biosensor exhibited an ultrawide dynamic range (10 aM-1 µM) and an ultralow detection limit (38 aM) for target miRNA-21 analysis. Furthermore, this biosensor can determine miRNA-21 expression in cell lysates of 100 human cervical cancer (HeLa) cells. Our results demonstrate that MoS2-AuNP nanocomposites have great potential in constructing biosensors for target molecule analysis.

4.
Analyst ; 2020 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-32588847

RESUMO

Zika virus (ZIKV) is a serious threat to human health due to its widespread human arboviral infections, and early diagnosis is one of the keys to preventing infections from spreading, but there is a lack of highly sensitive and specific detection. In this work, a target-mediated fuel-initiated molecular machine was proposed for the high-sensitive fluorescence assay of the ZIKV gene via strand displacement reaction-based signal recovery and cycling amplification. The molecular machine was prepared by modifying AuNP surfaces with specially designed lock-like DNAs (LLDs). The LLDs assembled with a hairpin DNA (H1) and a fluorescent aDNA can be opened under the trigger of the ZIKV gene and the strand displacement reactions are further initiated with the help of the DNA fuel (H2), which results in the release of the aDNAs and ZIKV genes from the AuNPs, causing the recovery of the fluorescence signal and the cyclic amplification of the gene. The target-mediated fuel-initiated molecular machines output an amplified fluorescence signal with the enhancement of 360%, and possess good sensitivity for detecting the ZIKV gene in serum with a linear calibration curve from 100 pM to 1 fM and a low limit of detection of 0.90 fM. The molecular machines can differentiate the ZIKV gene from the single base mismatched DNA obviously and show good recovery of ZIKV gene detection, which demonstrates the good specificity, reproducibility and reliability of the highly sensitive assay for the early detection of the virus.

5.
Theranostics ; 10(13): 5966-5978, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32483431

RESUMO

Rationale: Structural stability and size controllability are critical issues to semiconducting polymer nanoparticles (SPNs), which currently show great potential for theranostic applications. Methods: Herein, multi-responsive semiconducting polymer semi-interpenetrating nanoparticles (PDPP3T@PNIPAMAA IPNs) with highly stable structure and uniform size have been successfully designed by semi-interpenetrating technique. Results: It is proposed for the first time that PDPP3T@PNIPAMAA IPNs were prepared with "reinforced concrete" particle structure, which is even resistant to organic solvent such as ethanol and THF. By adjusting the polymerization time, the obtained PDPP3T@PNIPAMAA IPNs exhibit uniform and controllable particle size with extremely low polydispersity index (~0.037) at 1 h of reaction time. The presence of pH/light/GSH multi-responsive semi-interpenetrating network in PDPP3T@PNIPAMAA IPNs dramatically increase their drug loading efficiency (92.64%), which is significantly higher than previously reported comparable SPNs-based drug delivery systems. Additionally, PDPP3T@PNIPAMAA-DOX IPNs further provide improved therapeutic efficacy by the combination of chemotherapy and photothermal therapy with controllably regulated release of doxorubicin (DOX). In vitro and in vivo results indicate that PDPP3T@PNIPAMAA-DOX IPNs are able to release drugs at controlled rate by pH/light/GSH regulation and offer PAI-guided chemo/photothermal combined therapy with excellent therapeutic efficacy. Conclusions: The semi-interpenetrating network method may be generally extended for the preparation of a wide range of organic polymer nanoparticles to achieve ultrahigh structural stability, precise particle size controllability and excellent drug loading capacity.

6.
Ultrason Sonochem ; 67: 105188, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32473543

RESUMO

Stent placement is an effective treatment for atherosclerosis, but is suffered from in-stent restenosis (ISR) caused by stent mechanical damage. Conventional ISR treatment such as drug-eluting stents (DES) is challenged by the low therapeutic efficacy and severe complications, unchangeable drug dosage for individuals, and limited drug penetration in the vascular tissue. We hypothesize that magnetic targeting and deep-penetrating delivery strategy by magnetic guidance and ultrasound stimulation might be an effective approach for ISR treatment. In the present study, antiproliferative drug (paclitaxel, PTX) loaded poly (lactide-co-glycolide) (PLGA) nanoparticles (PLGA-PTX) were embedded within the shells of the magnetic nanoparticle coated microbubbles (MMB-PLGA-PTX). Once being targeted to the stent under a magnetic field, a low intensity focused ultrasound (LIFU) is applied to activate stable microbubble oscillations, thereby triggering the release of PLGA-PTX. The generated mechanical force and microstreaming facilitate the penetration of released PLGA-PTX into the thickened vascular tissue and enhance their internalization by smooth muscle cells (SMCs), thereby reducing the clearance by blood flow. In an ex vivo experiment, magnetic targeting improved the accumulation amount of MMB-PLGA-PTX by 10 folds, while the LIFU facilitated the penetration of released PLGA-PTX into the tunica media region of the porcine coronary artery, resulting in prolonged retention time at the stented vascular tissue. With the combination effects, this strategy holds great promise in the precision delivery of antiproliferative drugs to the stented vascular tissue for ISR treatment.

7.
Environ Pollut ; 263(Pt B): 114571, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32320904

RESUMO

Perfluorooctane sulfonate (PFOS) has been widely used as a surface coating for household products. It still exists in living environments despite being restricted, due to its bioaccumulation and long half-life. Studies have shown that PFOS has the ability to induce adipogenic differentiation of human cells. Human mesenchymal stem cells (hMSCs) distributed within the adipose tissue might be a potential target of accumulated PFOS. However, traditional end-point toxicity assays failed to examine the subtle changes of cellular function exposed to low-dose persistent organic pollutants in real time. In the present work, highly sensitive and long-retained (more than 30 days) fluorescence based polymeric nanosensors were developed and employed for real-time assessment of cellular functions. hMSCs were engineered with sensor molecules encapsulated poly (lactic-co-glycolic acid) (PLGA) particles. Once internalized by hMSCs, PLGA particles continuously release and replenish sensor molecules to cytoplasm, resulting in prolonged fluorescence signal against photo bleaching and dilution by exocytosis. With this method, the dynamic changes of viability, ROS induction, and adipogenic differentiation related mRNA expression of hMSCs were monitored. PFOS with the concentration as low as 0.1 µM can induce cellular ROS and enhance the PPARγ and ap2 mRNA expression, suggesting the effect on promoting adipogenic differentiation of hMSCs.


Assuntos
Células-Tronco Mesenquimais , PPAR gama , Ácidos Alcanossulfônicos , Citoplasma , Fluorcarbonetos , Humanos , RNA Mensageiro
8.
J Am Chem Soc ; 142(19): 8782-8789, 2020 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-32311267

RESUMO

Ultraviolet (UV) light has long been known to damage nucleic acids. In this work, a DNA origami radiometer has been developed for measuring UV exposure by monitoring the morphological evolution of DNA origami nanostructures. Unlike linear DNA strands that tend to be degraded into small segments upon UV exposure, the structural complexity and interstrand connectivity of DNA origami remarkably alter the pathway of UV-induced DNA damage. A general pathway of expansion, distortion, and final disintegration is observed for DNA origami regardless of their shape and size; however the deformation kinetics is positively correlated with the number of nicks in the nanostructure. This structural continuity-dependent deformation can be translated into a DNA-based radiometer for measuring UV dose in the environment.

9.
J Appl Toxicol ; 40(8): 1131-1140, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32167196

RESUMO

The potential toxicity of cadmium-containing quantum dots (QDs) has received much attention because of increasing biomedical applications. However, little has been known about how cadmium telluride (CdTe) QDs influence the gut microbiota and lipid metabolism. In this study, mice were exposed orally to CdTe QDs (200 µL of 0.2, 2, 20 or 200 µm; twice per week) for 4 weeks. The oral experiments showed CdTe QD exposure led to a decrease of the Firmicutes/Bacteroidetes (F/B) ratio of gut microbiota, which highly negatively correlated with the low-density lipoprotein (LDL), triglyceride (TG) and total cholesterol (TC) levels in serum. In addition, the low-dose (0.2 and 2 µm) CdTe QDs significantly increased the diversity of gut microbiota, and did not elevate the LDL, TG and TC levels in serum. The medium dose (20 µm) of CdTe QDs caused the biggest decrease of the F/B ratio, so it significantly increased the LDL, TG and TC levels compared with the control. Furthermore, high-dose (200 µm) CdTe QDs caused various toxicities in the histopathology of liver and intestine, liver function and intestinal immunity, but did not significantly lead to changes of the LDL, TG and TC levels in serum. This study demonstrates that high-dose oral CdTe QDs mainly lead to tissue damage of the liver and intestine, while the medium and low doses of oral CdTe QDs induce shifts of gut microbiota structure, which are associated with blood lipid levels.

10.
Biomater Sci ; 8(8): 2227-2233, 2020 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-32129325

RESUMO

An enveloped virus with soft and rough shells has strong penetration ability for cells. Inspired by the unique structure of virus, we successfully constructed virus-mimicking mesoporous organosilica nanocapsules (denoted as VMONs) for the first time by decorating small-sized silica nanoparticles on soft mesoporous organosilica hollow spheres. TEM and SEM images reveal that the prepared VMONs display uniform diameters (240 nm), a soft framework, a rough surface, and excellent dispersity. Quantitative nanomechanical mapping further demonstrates that the VMONs possess an extremely low Young's modulus (36 MPa) and a scraggly surface. In view of the successful construction of the virus-mimicking nanocapsules, the VMONs are further modified with human serum albumin (HSA) and Cy5.5-maleimide (Mal-Cy5.5) to investigate their cell penetration ability. Flow cytometry analysis reveals that the internalization of VMONs@HSA-Cy5.5 increases 2.74-fold compared to that of the conventional mesoporous nanosphere. Confocal laser scanning microscopy images show that the VMONs@HSA-Cy5.5 diffuses deeper for multicellular spheroids compared to both hard and soft mesoporous organosilica nanospheres. The penetration ability of the VMONs and SMONs increases 18.49 and 6.13-fold compared to that of MONs at the depth of 60 µm. Thanks to the excellent cellular penetration ability, the virus-mimicking VMONs@HSA-Cy5.5 can effectively deliver the anticancer drug doxorubicin (Dox) into drug-resistant MCF-7/ADR human breast cancer cells and significantly enhance the chemotherapeutic efficacy. Taken together, the constructed virus-mimicking organosilica nanocapsules with a soft framework and a rough surface possess strong cellular internalization and tumor penetration abilities, providing a unique and effective nanoplatform for biomedical applications.

11.
Nanoscale ; 12(14): 7776-7781, 2020 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-32215408

RESUMO

A novel composite nanomaterial is prepared by growing small Au nanoparticles on two-dimensional covalent organic framework nanosheets (Au NPs/COF NSs). The synthesized hybrid nanosheets are used as a new platform for multiplexed detection of hepatitis A virus DNA (HAV) and hepatitis B virus DNA (HBV). Additionally, this sensing platform based on Au NPs/COF NSs can be used as a candidate for monitoring the distribution of potassium ions (K+) and the intracellular K+ level in living cells. Accordingly, the sensing systems based on hybrid Au NPs/COF NSs have shown great potential for the investigation of biomolecules and related biological applications.

12.
J Org Chem ; 85(5): 3029-3040, 2020 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-32031804

RESUMO

An efficient approach to invent diversely substituted indole-fused phthalazines from in situ formed (2-alkynylbenzylidene)hydrazines under metal-free conditions via selective radical cyclization has been developed. Notably, this 6-exo-dig addition-cyclization tandem procedure proceeds under air atmosphere and shows a broad substrate suitability, as well as avoids harmful byproducts, which complies with the concept of green synthesis.

13.
Analyst ; 145(4): 1219-1226, 2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-31907495

RESUMO

The development of convenient sensing probes and strategies for the highly sensitive and specific detection of biomolecules is greatly significant for the diagnosis of diseases. Herein, a dual signal amplification strategy comprising target-triggered recycling and duplex-specific nuclease (DSN)-mediated amplifications was designed and proposed for a highly sensitive fluorescence assay of nucleic acids. In this strategy, three special hairpin structured single-stranded DNAs (i.e., H1, H2 and H3) were designed, and target-triggered recycling was operated on H1-modified AuNPs (i.e., AuNP-H1 probes) in the presence of target DNA, H2 and H3 to form trefoil DNAs on AuNPs (i.e., AuNP-trefoil). DSN was then incubated with AuNP-trefoil to cleave the double-stranded trefoil DNAs, causing the ROX molecules labelled on H2 and H3 to fall off the AuNPs, which resulted in the recovery of the previous AuNP-quenched fluorescence signal of ROX. The sensing mechanism was confirmed by polyacrylamide gel electrophoresis and fluorescence characterizations, and the sensing strategy was optimized from several aspects, such as the MCH blocking time of the AuNP-H1 probes (20 min) and the concentration (0.3 U) and immobilization time (15 min) of DSN. The practicability of the probes and the dual signal amplification strategy was investigated by a fluorescence assay of target DNA in human serum. A good linear calibration curve from 50 fM to 100 pM was obtained with a low detection limit of 47.68 fM. The sensing strategy showed good specificity, which could efficiently distinguish the target DNA from the single-base mismatched (SM) and completely unmatched (UM) DNAs. The recovery values ranging from 91.85% to 106.3% with the relative standard deviations (RSD) less than 7.30% also illustrated the good reliability of the proposed sensing probes and strategy. The AuNP-H1 probes and dual signal amplification strategy provide highly effective diagnostic agents and method for the analysis of disease-related nucleic acid biomarkers at the molecular level for early disease detection.

14.
Biotechnol J ; 15(1): e1800741, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31464360

RESUMO

Plasmonic nanomaterials, especially Au and Ag nanomaterials, have shown attractive physicochemical properties, such as easy functionalization and tunable optical bands. The development of this active subfield paves the way to the fascinating biosensing platforms. In recent years, plasmonic nanomaterials-based sensors have been extensively investigated because they are useful for genetic diseases, biological processes, devices, and cell imaging. In this account, a brief introduction of the development of optical biosensors based on DNA-functionalized plasmonic nanomaterials is presented. Then the common strategies for the application of the optical sensors are summarized, including colorimetry, fluorescence, localized surface plasmon resonance, and surface-enhanced resonance scattering detection. The focus is on the fundamental aspect of detection methods, and then a few examples of each method are highlighted. Finally, the opportunities and challenges for the plasmonic nanomaterials-based biosensing are discussed with the development of modern technologies.

15.
Chem Commun (Camb) ; 56(6): 960-963, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31859290

RESUMO

Direct access to benzo-fused aza-macrolides was successfully achieved through iridium-catalysed intermolecular decarboxylative coupling of vinylethylene carbonates with isatoic anhydrides under relatively mild reaction conditions. Notably, this reaction proceeded through sequential allyl-amination/macrolactonization upon extrusion of CO2. Moreover, favourable fluorescence properties could be observed in the title macrocyclic products.

16.
Nat Commun ; 10(1): 5469, 2019 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-31784537

RESUMO

Biomolecular cryptography exploiting specific biomolecular interactions for data encryption represents a unique approach for information security. However, constructing protocols based on biomolecular reactions to guarantee confidentiality, integrity and availability (CIA) of information remains a challenge. Here we develop DNA origami cryptography (DOC) that exploits folding of a M13 viral scaffold into nanometer-scale self-assembled braille-like patterns for secure communication, which can create a key with a size of over 700 bits. The intrinsic nanoscale addressability of DNA origami additionally allows for protein binding-based steganography, which further protects message confidentiality in DOC. The integrity of a transmitted message can be ensured by establishing specific linkages between several DNA origamis carrying parts of the message. The versatility of DOC is further demonstrated by transmitting various data formats including text, musical notes and images, supporting its great potential for meeting the rapidly increasing CIA demands of next-generation cryptography.


Assuntos
Bacteriófago M13/genética , Segurança Computacional , Computadores Moleculares , DNA/genética , Comunicação , Confidencialidade , Humanos
17.
Chem Commun (Camb) ; 55(100): 15145-15148, 2019 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-31790115

RESUMO

A lipase-triggered drug release nanoplatform (PGL-DPP-FLU NPs) for multi-modal antifungal therapy is developed. The lipases secreted by C. albicans can accelerate FLU release. The ROS and heat produced by PGL-DPP-FLU NPs make C. albicans more vulnerable to FLU, thereby PGL-DPP-FLU NPs exhibit high performance for combating azole-resistant C. albicans biofilms and wound infection.


Assuntos
Antifúngicos/farmacologia , Azóis/química , Candida albicans/efeitos dos fármacos , Lipase/metabolismo , Nanopartículas/química , Animais , Antifúngicos/química , Antifúngicos/uso terapêutico , Azóis/farmacologia , Candidíase/tratamento farmacológico , Candidíase/patologia , Candidíase/veterinária , Farmacorresistência Fúngica/efeitos dos fármacos , Etilenoglicóis/química , Fluconazol/química , Cetonas/química , Lasers , Camundongos , Fotoquimioterapia , Fototerapia , Poliésteres/química , Pirróis/química
18.
ACS Nano ; 13(12): 13797-13808, 2019 12 24.
Artigo em Inglês | MEDLINE | ID: mdl-31696705

RESUMO

Antibacterial agents with high antibacterial efficiency and bacteria-binding capability are highly desirable. Herein, we describe the successful preparation of Cu2WS4 nanocrystals (CWS NCs) with excellent antibacterial activity. CWS NCs with small size (∼20 nm) achieve more than 5 log (>99.999%) inactivation efficiency of both Staphylococcus aureus (Gram-positive) and Escherichia coli (Gram-negative) at low concentration (<2 µg mL-1) with or without ambient light, which is much better than most of the reported antibacterial nanomaterials (including Ag, TiO2, etc.) and even better than the widely used antibiotics (vancomycin and daptomycin). Antibacterial mechanism study showed that CWS NCs have both enzyme-like (oxidase and peroxidase) properties and selective bacteria-binding ability, which greatly facilitate the production of reactive oxygen species to kill bacteria. Animal experiments further indicated that CWS NCs can effectively treat wounds infected with methicillin-resistant Staphylococcus aureus (MRSA). This work demonstrates that CWS NCs have the potential as effective antibacterial nanozymes for the treatment of bacterial infection.

19.
Adv Mater ; 31(51): e1905467, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31696973

RESUMO

Silicon nanostructure color has achieved unprecedented high printing resolution and larger color gamut than sRGB. The exact color is determined by localized magnetic and electric dipole resonance of nanostructures, which are sensitive to their geometric changes. Usually, the design of specific colors and iterative optimization of geometric parameters are computationally costly, and obtaining millions of different structural colors is challenging. Here, a deep neural network is trained, which can accurately predict the color generated by random silicon nanostructures in the forward modeling process and solve the nonuniqueness problem in the inverse design process that can accurately output the device geometries for at least one million different colors. The key results suggest deep learning is a powerful tool to minimize the computation cost and maximize the design efficiency for nanophotonics, which can guide silicon color manufacturing with high accuracy.

20.
Nanoscale ; 11(40): 18881-18893, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31596295

RESUMO

Nanomaterials with high catalytic activity and good SERS properties can be used for sensitive and real-time in situ tracking of a catalytic process via SERS, which can be a powerful tool for investigating the products and mechanisms of the catalytic reaction. In the present work, Au@AgPt NPs with a {431}-faceted hexoctahedral Au core and an AgPt alloy shell exhibiting enhanced catalysis and good SERS activity were prepared by a facile silver-mediated temperature-controlled selective deposition of Pt. The complex hexoctahedral Au nanoparticles were synthesized first as nano-templates, followed by coating with a thin layer of Ag. Then, a temperature-controlled synthesis method for preferably depositing Pt on the hexoctahedral Au NPs was proposed to prepare Au@AgPt NPs. With the increase of the synthesis temperature, the Pt atoms were controlled to selectively deposit on the tips, edges or the entire surface of the nano-templates. By systematically investigating the effects of temperature, precursor consumption and synthesis time on the morphology, composition, optical properties, catalysis and SERS properties of the Au@AgPt NPs, the kinetic and thermodynamic mechanisms of the deposition of Pt on hexoctahedral Au nanoparticles were explored. The performance of the Au@AgPt NPs in SERS-based real-time in situ monitoring of the catalytic reaction was also investigated and verified. Besides, it is easy to regulate and control their SERS and catalytic performances through the selective deposition of Pt, according to the demand of the catalytic reaction and SERS monitoring. This work not only presents a new Au@AgPt nanostructure with good catalytic and SERS properties, but also develops a facile, universal and controllable method for selective deposition of Pt on Au nano-templates with a variety of morphologies.

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