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1.
Adv Healthc Mater ; : e2401885, 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39036819

RESUMEN

DNA nanotechnology combines structural design with therapeutic functions via programmable DNA motifs, but faces challenges in drug loading capacity. Herein a pore-engineering strategy is reported to develop a highly porous, universal DNA nano-vehicle through coordination self-assembly, cryo-engineering, and supramolecular chemistry, adapting to diverse cargo loading with desired theranostic agents. Thus, the complex synthesis and compatibility challenges typically associated with switching between different drug carriers are avoided. To this end, Cu2+ and nucleic acid therapeutic G3139 self-assemble into a prefabricated solid nanostructure, which subsequently undergoes ultrafast freezing and sublimation to introduce porosity, forming highly porous Cu-G3139 nanoparticles (CG NPs). The porous CG NPs efficiently accommodate diverse therapeutic molecules, from chemotherapeutics to non-chemotherapeutic agents, facilitated by positively-charged cyclodextrin. As a proof-of-concept, the photosensitizer indocyanine green (ICG) is loaded and coated with tannic acid (TA) to form CICG@TA, enabling remarkable photothermal and fluorescence imaging-guided synergistic tumor ablation. This work represents the first demonstration of sublimation-induced pore formation in metal-DNA hybrid nanoparticles without chemical etching, offering a scalable "plug-and-play" platform for personalized cancer therapy without redesign. This versatile pore-engineering strategy, merging supramolecular chemistry with cryo-engineered porosity, opens up new avenues for efficient, customized multidrug delivery for diverse tumor theranostic applications.

2.
J Am Chem Soc ; 146(28): 19360-19368, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39015060

RESUMEN

High-efficiency generation of spin-triplet states in organic molecules is of great interest in diverse areas such as photocatalysis, photodynamic therapy, and upconversion photonics. Recent studies have introduced colloidal semiconductor nanocrystals as a new class of photosensitizers that can efficiently transfer their photoexcitation energy to molecular triplets. Here, we demonstrate that metallic Ag nanoparticles can also assist in the generation of molecular triplets in polycyclic aromatic hydrocarbons (PAHs), but not through a conventional sensitization mechanism. Instead, the triplet formation is mediated by charge-separated states resulting from hole transfer from photoexcited PAHs (anthracene and pyrene) to Ag nanoparticles, which is established through the rapid formation and subsequent decay of molecular anions revealed in our transient absorption measurements. The dominance of hole transfer over electron transfer, while both are energetically allowed, could be attributed to a Marcus inverted region of charge transfer. Owing to the rapid charge separation and the rapid spin-flip in metals, the triplet formation yields are remarkably high, as confirmed by their engagement in production of singlet oxygen with a quantum efficiency reaching 58.5%. This study not only uncovers the fundamental interaction mechanisms between metallic nanoparticles and organic molecules in both charge and spin degrees of freedom but also greatly expands the scope of triplet "sensitization" using inorganic nanomaterials for a variety of emerging applications.

3.
J Fluoresc ; 2023 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-37856063

RESUMEN

Fluoride ion is a strong Lewis base and one of the essential trace elements in human body. It plays a very important role in human health and ecological balance. The deficiency or excessive intake of fluoride ions will cause serious health problems, so the development of a sensitive and accurate detection method for fluoride ions is very important. The colorimetric and/or fluorescence sensing method has been a long standing attractive technique with high sensitivity and fast response. To date, most reported probes for fluoride ion are applicable only in organic solvents or organic-containing aqueous solutions. However, the probes for fluoride ion used in aqueous solution are more practically needed in view of environment protection and human health. In this paper, the materials and designing ideas of the colorimetric and/or fluorescent probes for fluoride ion based on different detection mechanisms in recent years were reviewed. Two main categories including formation of hydrogen bonds and formation of coordination covalent bonds were discussed. The latter one is further subdivided into three types, formation of B-F bond, formation of Si-F bond and formation of Mn+-F bond.

4.
Anal Chem ; 95(38): 14421-14429, 2023 09 26.
Artículo en Inglés | MEDLINE | ID: mdl-37695215

RESUMEN

Real-time monitoring of early antitumor efficacy is one of the key issues in realizing high-efficiency and more precise tumor treatment. As a highly specific event in the early stage of apoptosis, the release of cytochrome c may act as a key biomarker for monitoring cell apoptosis. However, achieving real-time monitoring of the cytochrome c release in vivo remains a challenge. Herein, we report a novel integrated nanosystem named DFeK nanoparticle (DFeK NP) to achieve a favorable collaboration of inducing tumor cell apoptosis and monitoring early therapeutic efficacy, which combined the cytochrome c-activated DNA nanoprobe cApt-App with pro-apoptotic peptide [KLAKLAK]2 and ferrous ions. [KLAKLAK]2 can target the mitochondria to disrupt the mitochondrial membrane together with reactive oxygen species produced by ferrous ions via the Fenton reaction to promote mitochondrial damage. Then, cytochrome c is released from damaged mitochondria to trigger apoptosis, further activating the cApt-App probe from the fluorescence "off" state to the "on" state. The cytochrome c-specific "off-to-on" transition was successfully applied in fluorescence imaging of cytochrome c in vivo and thus achieved real-time early therapeutic efficacy monitoring. Collectively, this work presents a valuable integrated tool for tumor inhibition and therapeutic efficacy evaluation to realize more precise and more effective tumor treatment.


Asunto(s)
Apoptosis , Citocromos c , Muerte Celular , Hierro , Iones
5.
Biomater Sci ; 10(13): 3569-3574, 2022 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-35635189

RESUMEN

Programmable cancer therapies may perfectly prevent mutual drug restrictions, however, developing an efficient codelivery system with such an ability remains challenging. We herein first demonstrate the use of supramolecular-mediated dual-functional DNA nanocomposites for programmable chemodynamic therapy (CDT) and chemotherapy (CT), in which a water-soluble cyclodextrin-resveratrol (CD-Res) complex can be facilely encapsulated during the coassembly of Fe2+ and DNA to form the desired spherical nanocomposites. After endocytosis, the released Fe2+ can immediately trigger an endogenous Fenton reaction, inducing ferroptosis for CDT and ˙OH depletion, followed by the sustained release of the protected Res from the CD cavity. This process improves the efficacy of CT by preventing Res from the oxidation of ˙OH. The as-prepared nano-composites can sufficiently accumulate in the tumor, demonstrating an adequate programmable therapeutic performance without serious toxicity. Thus, a facile, fresh and changeable strategy for the design of antitumor therapies is presented.


Asunto(s)
Ferroptosis , Nanocompuestos , Neoplasias , Línea Celular Tumoral , ADN , Humanos , Peróxido de Hidrógeno , Neoplasias/tratamiento farmacológico
6.
Artículo en Inglés | MEDLINE | ID: mdl-38094222

RESUMEN

This study explored the effects of Hugan Buzure (HBR) on cell apoptosis and autophagy in hepatocellular carcinoma (HCC) and the molecular mechanisms of the PI3K/Akt/mTOR signaling pathway. HepG2 and Huh7 cell viability was detected by the tetramethylazolium salt colorimetric (MTT) method. Cell proliferation was measured using the colony formation method. Hoechst 33258 staining and flow cytometry were employed to detect apoptosis. In addition, immunofluorescence was carried out to evaluate the expression of LC3. Western blot was performed to detect the expression of Bcl-2, Bax, Caspase-3, LC3, Beclin1, p62 (SQSTM1), and PI3K/Akt/mTOR signal pathway-related proteins in HCC cells. This work verified that HBR reduced HepG2 and Huh7 cell proliferation in a concentration-dependent manner. Treatment with HBR caused an obvious improvement of the apoptosis rate, accompanied by the increase in Bax/Bcl2, Caspase3, LC3II, and Beclin1 levels, respectively. Furthermore, HBR downregulated the expression of p62, p-PI3K, p-Akt, and p-mTOR proteins. HBR combined with HCQ enhanced HBR-induced apoptosis. In conclusion, HBR induced autophagy and apoptosis through PI3K/Akt/mTOR signaling pathway, leading to HCC cell death. This research preliminarily suggested the potential role of HBR in the treatment of HCC.

7.
Small ; 15(41): e1902551, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31423746

RESUMEN

Developing nonprecious electrocatalysts with superior activity and durability for electrochemical water splitting is of great interest but challenging due to the large overpotential required above the thermodynamic standard potential of water splitting (1.23 V). Here, in situ growth of Fe2+ -doped layered double (Ni, Fe) hydroxide (NiFe(II,III)-LDH) on nickel foam with well-defined hexagonal morphology and high crystallinity by a redox reaction between Fe3+ and nickel foam under hydrothermal conditions is reported. Benefiting from tuning the local atomic structure by self-doping Fe2+ , the NiFe(II,III)-LDH catalyst with higher amounts of Fe2+ exhibits high activity toward oxygen evolution reaction (OER) as well as hydrogen evolution reaction (HER) activity. Moreover, the optimized NiFe(II,III)-LDH catalyst for OER (O-NiFe(II,III)-LDH) and catalyst for HER (H-NiFe(II,III)-LDH) show overpotentials of 140 and 113 mV, respectively, at a current density of 10 mA cm-2 in 1 m KOH aqueous electrolyte. Using the catalysts for overall water splitting in two-electrode configuration, a low overpotential of just 1.54 V is required at a benchmark current density of 10 mA cm-2 . Furthermore, it is demonstrated that electrolysis of the water device can be drived by a self-powered system through integrating a triboelectric nanogenerator and battery, showing a promising way to realize self-powered electrochemical systems.

8.
ACS Appl Mater Interfaces ; 11(2): 2042-2049, 2019 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-30562455

RESUMEN

Solid-state lithium batteries (SSLBs) are promising technologies with great potential in improving safety and energy density, compared with the traditional liquid based lithium ion batteries. However, the bottleneck of SSLBs lies in the issues of poor interface contact and low electrolyte conductivity. In this work, the crystal structure of garnet-type Li6.25Ga0.25La3Zr2O12 (LGLZO) was engineered more rigidly with subdued atoms displacement by fluorine doping and thus smoother and faster lithium ion diffusion paths are formed. The ionic conductivity of garnet-type electrolyte is significantly increased from 5.43 × 10-4 S/cm to 1.28 × 10-3 S/cm at 25 °C and the activation energy is reduced from 0.33 to 0.28 eV. The solid-state symmetric cell consisting of F doped Li6.25Ga0.25La3Zr2O12 electrolyte and lithium metal has lower resistance and displays stable lithium plating/stripping for over 650 h with smaller overpotentials than those on LGLZO electrolyte. Moreover, the all solid-state lithium battery with F-LGLZO electrolyte and LiFePO4 composite electrode exhibits an improved rate capability, which can still keep 132.9 mAh/g at 1 C. Fluorine substitution in garnet-type electrolyte opens new avenues to design new solid-state electrolytes for practical applications of SSLBs.

9.
ACS Appl Mater Interfaces ; 10(19): 16474-16481, 2018 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-29701449

RESUMEN

Graphene hydrogels (GHs) and their composites have attracted wide attention because of the special structure of graphene assembly and exceptional electrochemical performance as electrodes for energy storage devices. Here, we report a GH with three-dimensional architecture prepared by a hydrothermal method via a self-assembled process in glucose and ammonia system as well as subsequent freeze-drying. The δ-MnO2/GH composite was then obtained by immersing GH in KMnO4 solution with a certain concentration under heat treatment. The asymmetric supercapacitor MnO2/GH//GH consisting of pseudocapacitive nanosheet-like δ-MnO2/GH as the cathode and electric double-layer capacitive GH as the anode provides high energy density of 34.7 W h/kg at a power density of 1.0 kW/kg. Importantly, it is found that the pseudocapacitive behavior of MnO2 has great effects on the rate performance of the supercapacitor, which is identified by kinetic analysis.

10.
Environ Monit Assess ; 190(4): 197, 2018 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-29516253

RESUMEN

Railway transportation is an important transportation mode. However, railway transportation causes heavy metal pollution in surrounding soils. Heavy metal pollution has a serious negative impact on the natural environment, including a decrease of enzyme activities in soil and degradation of sensitive ecosystems. Some studies investigated the heavy metal pollution at railway stations or certain transportation hubs. However, the pollution accumulated in artificial cut slope soil all along the rails is still questioned. The interest on non-point source pollution from railways is increasing in an effort to protect the soil quality along the line. In this study, we studied spatial distributions of heavy metals and five enzyme activities, i.e., urease (UA), saccharase (SAC), protease (PRO), catalase (CAT), and polyphenol oxidase (POA) in the soil, and the correlation among them beside three different railways in Sichuan Province, China, as well. Soil samples were respectively collected from 5, 10, 25, 50, 100, and 150 m away from the rails (depth of 0-8 cm). Results showed that Mn, Cd, Cu, and Zn were influenced by railway transportation in different degrees while Pb was not. Heavy metal pollution was due to the abrasion of the gravel bed as well as the tracks and freight transportation which caused more heavy metal pollution than passenger transportation. Enzymatic activities were significantly negatively correlated with heavy metals in soils, especially Zn and Cu. Finally, it is proposed that combined use of PRO and POA activities could be an indicator of the heavy metal pollution in cut slope soils. The protective measures aimed at heavy metal pollution caused by railway transportation in cut slope soils are urgent.


Asunto(s)
Monitoreo del Ambiente/métodos , Hidrolasas/metabolismo , Metales Pesados/análisis , Oxidorreductasas/metabolismo , Vías Férreas , Contaminantes del Suelo/análisis , Suelo/química , China , Ecosistema , Microbiología del Suelo
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