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1.
ACS Appl Bio Mater ; 4(7): 5695-5706, 2021 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-35006739

RESUMEN

Fluorescent surgical navigation can effectively aid tumor resection. As one of the most popular near-infrared (NIR) fluorophores, cyanine dye has the outstanding optical ability and the potential to act as a fluorescence probe for tumors. Herein, we report a polyethylene glycol-modified amphiphilic cyanine dye (Cy7-NPC) with an NIR luminescence performance, which can self-assemble to form uniform nanomicelles (Cy7-NPC-S) and which can be applied for the optical imaging of abdominal tumors and for fluorescence imaging-guided precision tumor resection. When applied to biological imaging, Cy7-NPC-S showed high biological safety, strong tissue penetration depth for optical imaging, and high optical imaging resolution. Intraperitoneal administration of Cy7-NPC-S produced remarkable imaging efficacy in abdominal tumors. Compared with intravenous injection, abdominal tumors took up intraperitoneal Cy7-NPC-S faster and in greater quantities, thus enabling Cy7-NPC-S to facilitate accurate recognition and extirpation of abdominal tumors in fluorescence-guided surgery. We believe that metabolizable Cy7-NPC-S with NIR luminescence has promising applications and value in the fields of in vivo imaging and fluorescent surgical navigation.


Asunto(s)
Neoplasias Abdominales , Cirugía Asistida por Computador , Neoplasias Abdominales/diagnóstico por imagen , Colorantes Fluorescentes , Humanos , Inyecciones Intraperitoneales , Imagen Óptica/métodos , Cirugía Asistida por Computador/métodos
2.
ACS Appl Mater Interfaces ; 12(52): 57768-57781, 2020 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-33326213

RESUMEN

Solid tumors inevitably develop radioresistance due to low oxygen partial pressure in the tumor microenvironment. Despite numerous attempts, there are still few effective ways to avoid the hypoxia-induced poor radiotherapeutic effect. To overcome this problem, platinum (Pt) nanodots were fabricated into a mesoporous bismuth (Bi)-based nanomaterial to construct a biodegradable nanocomposite BiPt-folic acid-modified amphiphilic polyethylene glycol (PFA). BiPt-PFA could act as a radiosensitizer to enhance the absorption of X-rays at the tumor site and simultaneously trigger response behaviors related to the tumor microenvironment due to the enrichment of materials in the tumor area. During this process, the Bi-based component consumed glutathione via coordination, thus altering the oxidative stress balance, while Pt nanoparticles catalyzed the decomposition of hydrogen peroxide to generate oxygen, thereby relieving tumor hypoxia. Both Pt and Bi thus co-modulated the tumor microenvironment to improve the radiotherapeutic effect. In addition, Pt dots in BiPt-PFA had strong near-infrared absorption ability and created an intensive photothermal therapeutic effect. Modulation of the tumor microenvironment could thus improve the therapeutic effect in hypoxic tumors by a combination of photothermal therapy and enhanced radiotherapy. BiPt-PFA, as a biodegradable nanocomposite, may thus modulate the tumor microenvironment to enhance the hypoxic tumor therapeutic effect by thermoradiotherapy.


Asunto(s)
Bismuto/química , Nanocompuestos/química , Fármacos Sensibilizantes a Radiaciones/química , Hipoxia Tumoral/efectos de los fármacos , Microambiente Tumoral/efectos de los fármacos , Animales , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/efectos de la radiación , Humanos , Hipertermia Inducida , Nanopartículas del Metal/química , Ratones , Platino (Metal)/química , Polietilenglicoles/química , Porosidad , Fármacos Sensibilizantes a Radiaciones/farmacología , Seguridad , Solubilidad , Hipoxia Tumoral/efectos de la radiación , Microambiente Tumoral/efectos de la radiación , Agua/química
3.
ACS Omega ; 5(19): 10927-10938, 2020 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-32455213

RESUMEN

PbMoO4 materials were synthesized by the glycerol and hydrothermal methods, and AgCl nanoparticles were loaded onto the surface of PbMoO4 by using the precipitation-deposition method. Finally, a AgCl/PbMoO4 photocatalyst was successfully prepared. X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, transmission electron microscopy, and UV-vis diffuse reflectance spectroscopy (UV-vis-DRS) were used to characterize the phase composition, morphology, and light absorption characteristics of the catalyst. An n-octane solution of dibenzothiophene (DBT) was used to simulate fluid catalytic cracking to make gasoline. The photocatalytic oxidation performance of DBT under visible light was studied in terms of the type of light source as well as of the catalyst, substrate, and AgCl content. The mechanism of photocatalytic oxidation was also studied. The results show that AgCl loading causes a red shift of the absorption edge of PbMoO4, which improves the photocatalytic activity of the material. When the AgCl loading was 25.0%, the amount of catalyst was 1.5 g/L, and the visible light irradiation time was 2.0 h, the highest desulfurization rate of DBT reached 97.0%.

4.
RSC Adv ; 10(6): 3380-3390, 2020 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-35497730

RESUMEN

In this study, ZIF-8 with a rhombic dodecahedron structure was prepared by a hydrothermal method. Then La(OH)3, was successfully loaded onto the ZIF-8 by an immersion deposition method, to form a lanthanide-based metal-organic framework (La@ZIF-8) composites. The structure and properties of La@ZIF-8 were verified by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), and zeta potential measurements. The optimum process conditions are discussed within the materials and methods. The effects of initial phosphorus concentration, dosage, pH and contact reaction time on the phosphorus removal performance of the nanomaterial were investigated. The results indicated that La@ZIF-8 exhibited an excellent adsorption capacity (147.63 mg g-1) and its phosphorus removal efficiency could reach as high as 99.7%. Experimental data were interpreted using different adsorption kinetic and isotherm models. The kinetic behavior conformed to the pseudo-second-order kinetic model, which indicated the chemisorption of phosphorus by La@ZIF-8. The adsorption behavior of phosphorus by La@ZIF-8 fitted well to the Langmuir isotherm model, suggesting a monolayer chemical adsorption process. The majority of the adsorbed phosphate could be desorbed by NaOH (2 mol L-1), and the removal efficiency of the recycled La@ZIF-8 reached 90%, even after the fifth cycle. The obtained results demonstrate the great application potential of the prepared La@ZIF-8 as a fascinating adsorbent for the removal of phosphate.

5.
Front Chem ; 7: 737, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31737609

RESUMEN

The aim of this study is to investigate the transformation of hydrogen-donor solvent tetralin in the direct liquefaction process of coal. Pure tetralin liquid as well as mixture of tetralin and Wucaiwan coal (WCW) were separately reacted under a liquefaction condition, and constituents of liquid product were analyzed by GC-MS. The results show that after the tetralin liquid reacts with high-pressure hydrogen, 90% of the reaction product is in liquid state, the gaseous products mainly include alkane gas and COx gas. When the reaction temperatures were set at 380 and 420°C, respectively, the corresponding transformation rates of tetralin can be 34.72 and 52.74%. At 380°C, the tetralin mainly plays a role of passing active hydrogen, while at 420°C, it mainly occurs dehydrogenation transformation to provide active hydrogen, as well as generate naphthalene, methyl indan, and substituted benzene, etc. Taking tetralin as the hydrogen-donor solvent, the WCW was performed liquefaction reaction, and the obtained results show that the transformation rates of tetralin are 69.76 and 83.86% at liquefaction temperatures of 380 and 420°C, respectively. Tetralin mainly occur to dehydrogenation transformation to generate naphthalene, followed by methyl indan, where contents order of main constituents of the liquefaction products were: naphthalene> tetralin > methyl indan.

6.
Se Pu ; 35(6): 565-571, 2017 Jun 08.
Artículo en Chino | MEDLINE | ID: mdl-29048781

RESUMEN

Large-pore silica microspheres were synthesized by utilizing weak cation exchange polymer beads as templates, N-trimethoxysilylpropyl-N,N,N-trimethylammonium chloride (TMSPTMA) as a structure-directing agent, tetraethoxysilane (TEOS) as a silica precursor, and triethanolamine as a weak base catalyst. The hydrolysis and condensation of the silica precursors occurred inside the templating polymer beads yielded polymer/silica composite microspheres. After the organic polymer templates were removed in the calcination step, large-pore silica microspheres were produced. The effects of different reaction conditions on the morphology, structure and dispersibility of the formed silica microspheres were investigated. It has been shown that when the volume ratio of TMSPTMA, TEOS and triethanolamine was 1:2:2, silica microspheres with pore size range of 50-150 nm and particle size around 2 µm were obtained. The as-prepared silica microspheres were then bonded with chlorodimethyloctadecylsilane (C18), packed into a 50 mm×4.6 mm column, and evaluated for the separations of some common standard proteins and soybean isolation proteins. The results showed that the large-pore silica spheres from this work have potentials for protein separation in HPLC.


Asunto(s)
Microesferas , Proteínas/aislamiento & purificación , Dióxido de Silicio , Cromatografía Líquida de Alta Presión , Hidrólisis , Tamaño de la Partícula , Polímeros , Porosidad
7.
Nanoscale ; 9(38): 14364-14375, 2017 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-28696454

RESUMEN

Overtreatment as a crucial modern medicine issue needs to be urgently addressed. Theranostic agents supply a unique platform and integrate multiple diagnosis and therapies to deal with this issue. In this study, a core-shell MnS@Bi2S3 nanostructure was fabricated via two step reactions for tri-modal imaging guided thermo-radio synergistic therapy. The mass ratio between the core and shell of the constructed MnS@Bi2S3 can be precisely controlled via cation exchange reaction. After surface PEGylation, MnS@Bi2S3-PEG nanoparticles exhibited excellent aqueous medium dispersibility for bioapplications. Based on the r1 and r2 relaxivity obtained from the MnS core and the strong near-infrared absorption and X-ray attenuation abilities of the Bi2S3 shell, the intratumoral injected MnS@Bi2S3-PEG can realize in vivo magnetic resonance, computer tomography, and photoacoustic tumor imaging under a single injection dose. Hyperthermia significantly boosts the efficacy of radiation therapy, showing synergistic tumor treatment efficacy. No obvious toxicity is monitored for the treated mice. Our study not only provides a new way to precisely construct the core-shell nanocomposite, but also presents a unique theranostic platform and unifies the solutions for the challenges related with high injection dose and overtreatment.


Asunto(s)
Hipertermia Inducida , Imagen Multimodal , Neoplasias Experimentales/terapia , Radioterapia , Nanomedicina Teranóstica , Animales , Bismuto/química , Cationes , Línea Celular Tumoral , Femenino , Compuestos de Manganeso/química , Ratones , Ratones Endogámicos BALB C , Nanopartículas/química , Neoplasias Experimentales/diagnóstico por imagen , Sulfuros/química
8.
Acta Biomater ; 58: 442-454, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28611005

RESUMEN

Two-dimensional transition metal dichalcogenides (TMDs) have been receiving great attention as NIR photothermal transducing agent in tumor photothermal therapy. Keeping in mind the low efficiency of the conventional top-down exfoliated 2D TMDs and the complexity of their surface modifications, we herein proposed a bottom-up strategy for the one-pot hydrothermal and controlled synthesis of surface polyvinyl pyrrolidone (PVP) modified WS2 nanosheets. The material design was based on the chelating-coordinating effect between the lone pair electrons of oxygen of PVP carbonyl group and the unoccupied orbital (5d orbitals) of tungsten. The WS2 nanosheets with synchronous surface PVP grafting showed an excellent photothermal conversion performance, while the surface anchored PVP guaranteed its colloidal stability. Moreover, the strong X-ray attenuation ability and near-infrared (NIR) absorbance of WS2-PVP360kDa enabled the sensitive in vitro and in vivo computed tomography and photoacoustic imaging. The WS2-PVP360kDa nanosheets were biocompatible and exhibited promising in vitro and in vivo anti-cancer efficacy. Findings in this report may greatly promote the design of colloidal stable and biocompatible 2D TMDs and their future clinical translations. STATEMENT OF SIGNIFICANCE: A bottom-up strategy for the one-pot and controlled synthesis of surface polyvinyl pyrrolidone (PVP) modified WS2 nanosheets was proposed for the first time. By hydrothermally treating the mixture solution of tetrathiotungstate and PVP, Owing to the chelating-coordinating effect between the lone pair electrons of oxygen of PVP carbonyl group and the unoccupied orbital (5d orbitals) of tungsten, PVP was synchronously graphed on WS2-PVP nanosheets surface. The formed WS2-PVP nanosheets were colloidal stable, biocompatible, and exhibited promising computed tomography, photoacoustic imaging and tumor photothermal therapy efficacy both in vitro and in vivo.


Asunto(s)
Nanoestructuras , Neoplasias Experimentales , Sulfuros , Tomografía Computarizada por Rayos X , Compuestos de Tungsteno , Animales , Línea Celular Tumoral , Humanos , Ratones , Nanoestructuras/química , Nanoestructuras/uso terapéutico , Neoplasias Experimentales/diagnóstico por imagen , Neoplasias Experimentales/tratamiento farmacológico , Povidona/química , Povidona/farmacología , Sulfuros/síntesis química , Sulfuros/química , Sulfuros/farmacología , Compuestos de Tungsteno/síntesis química , Compuestos de Tungsteno/química , Compuestos de Tungsteno/farmacología , Ensayos Antitumor por Modelo de Xenoinjerto
9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 28(7): 1535-8, 2008 Jul.
Artículo en Chino | MEDLINE | ID: mdl-18846714

RESUMEN

Jurassic coal in Northwest China is rich in resources and it is a necessary premise to reveal the chemical structure characteristics of the coal macerals in this region before the coal is put into reasonable and efficient use. Micro-FTIR technique was used to investigate the chemical composition and structures of vitrinite semifusinite and fusinite from Jurassic coal in Northwestern China. The results show that vitrinite and semifusinite have more aliphatic hydrogen, but fusinite has more aromatic hydrogen and C=O structure. The aliphatic hydrogen in semifusinite is higher than that in fusinite and it is this structure characteristic of semifusinite that led to the richer inertinite but higher reactivity of the Northwestern China coal. Not only vitrinite but also semifusinite and fusinite with weaker reducibility have less aliphatic hydrogen and more C=O structures than those with stronger reducibility. The different intensity of oxidation in the process of coalification is one of the causes that led to different type of reducibility.

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