Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 3 de 3
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
Bioengineered ; 13(1): 1013-1024, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34974800

RESUMO

The present research aimed to elucidate a convenient, safe and economic approach to induce the growth of endogenous bone tissue and bone regeneration. S-UNL-E was prepared using reverse-phase evaporation, and scutellarin encapsulation was subsequently compared. Meanwhile, the optimal preparation scheme was developed using an orthogonal method, and the particle size was determined using laser light scattering. In osteoblasts cultured in vitro, methyl thiazolyl tetrazolium (MTT), alkaline phosphatase (ALP) staining and alizarin red staining were used to detect the osteogenic effects of S-UNL-E. The results indicated that the optimal process conditions for S-UNL-E included mass ratios of phospholipid-cholesterol, phospholipid-breviscapine, phospholipid-sodium cholate, and phospholipid-stearamide were 2:1, 15:1, 7:1 and 7:1, respectively, and the mass of ethylenediamine tetramethylphosphonic acid (EDTMP) was 30 mg. The average particle size of S-UNL-E was 156.67 ± 1.76 nm, and Zeta potential was -28.77 ± 0.66 mv. S-UNL-E substantially increased the expression of ALP osteoblasts, elevated the content of osteocalcin protein and promoted the formation of mineralized nodules. Cells in the S-UNL-E group were densely distributed with integrated cell structure, and the actin filaments were clear and obvious. The findings demonstrated that S-UNL-E greatly promoted the differentiation and maturation of osteoblasts, and S-UNL-E (2.5 × 108) produced the most favorable effect in differentiation promotion. In conclusion, the present study successfully constructed an S-UNL-E material characterized by high encapsulation and high stability, which could effectively promote osteogenic differentiation and bone formation.


Assuntos
Citoesqueleto de Actina/metabolismo , Fosfatase Alcalina/metabolismo , Apigenina/farmacologia , Glucuronatos/farmacologia , Osteoblastos/citologia , Osteocalcina/metabolismo , Animais , Apigenina/química , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Composição de Medicamentos , Glucuronatos/química , Lipossomos , Nanopartículas , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Osteogênese , Tamanho da Partícula , Cultura Primária de Células , Ratos
2.
Chemosphere ; 81(7): 853-8, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20801482

RESUMO

Trinitroglycerin (TNG) is an industrial chemical mostly known for its clinical use in treating angina and manufacturing dynamite. The wide manufacture and application of TNG has led to contamination of vast areas of soil and water. The present study describes degradation of TNG with zero-valent iron nanoparticles (ZVINs) in water either present alone or stabilized on nanostructured silica SBA-15 (Santa Barbara Amorphous No. 15). The BET surface areas of ZVINs/SBA-15 (275.1 m2 g(-1)), as determined by nitrogen adsorption-desorption isotherms, was much larger than the non-stabilized ZVINs (82.0 m2 g(-1)). X-ray diffraction (XRD) showed that iron in both ZVINs and ZVINs/SBA-15 was present mostly in the α-Fe0 crystalline form considered responsible for TNG degradation. Transmission Electron Microscopy (TEM) showed that iron nanoparticles were well dispersed on the surface of the nanosilica support. Both ZVINs and ZVINs/SBA-15 degraded TNG (100%) in water to eventually produce glycerol and ammonium. The reaction followed pseudo-first-order kinetics and was faster with ZVINs/SBA-15 (k1 0.83 min(-1)) than with ZVINs (k1 0.228 min(-1)). The corresponding surface-area normalized rate constants, knorm, were 0.36 and 0.33 L h(-1) m(-2) for ZVINs/SBA-15 and ZVINs, respectively. The ZVINs/SBA-15 retained its original degradation efficiency of TNG after repeatedly reacting with fresh nitrate ester for five successive cycles. The rapid and efficient transformation of TNG with ZVINs/SBA-15, combined with excellent sustained reactivity, makes the nanometal an ideal choice for the clean up of water contaminated with TNG.


Assuntos
Ferro/química , Nanopartículas Metálicas/química , Nitroglicerina/química , Dióxido de Silício/química , Vasodilatadores/química , Catálise , Cinética , Nanopartículas Metálicas/ultraestrutura , Nitroglicerina/análise , Vasodilatadores/análise , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química , Purificação da Água/métodos
3.
J Nanosci Nanotechnol ; 5(4): 659-68, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16004135

RESUMO

This manuscript reports the ready synthesis of high-quality colloidal CdSe nanocrystals from tri-n-octylphosphine (TOP) and reports the optical properties of the resulting CdSe dispersed in nonpolar and polar environments. With cadmium oxide (CdO) as the Cd precursor and TOPSe as the Se source, the CdSe nanocrystals were synthesized in a reaction medium consisting of TOP. The synthetic approach is as simple as: the swift injection of a TOPSe/TOP solution into a CdO/TOP solution at one particular (high) temperature, with subsequent growth at a lower temperature. The temporal evolution of the optical properties, including absorption and luminescence, were monitored in detail. The photoluminescence (PL) properties of the TOP-capped CdSe investigated comprise the intensity, emission peak wavelength, full width at half maximum of the PL spectra, and stability; these PL properties are sensitive to the history of growth as well as the environment of dispersion. An appropriate parameter, termed "Sensitivity Index (SI)," is proposed to define the percent difference in the PL intensity that arises when the dots are dispersed in non-polar hexane (Hex) as compared to polar tetrahydrofuran (THF). The decrease in the PL efficiency on going from Hex to THF is attributed to changes in surface states rather than in the internal core as more ligands are removed in THF. Dilution experiments further confirm the suggestion of the ligand removal mechanism and provide a conceptual estimate of surface quality via the SI parameter. Due to a slow growth in size (the size of the nanocrystals is almost constant during early 20 min) and good PL stability (tested as PL changes after storage for days both in dispersed or solid states, as well as after UV-irradiation), we suggest that our synthetic approach is likely to be practical for large-scale CdSe nanocrystals with good PL stability.


Assuntos
Compostos de Cádmio/química , Coloides/química , Nanotecnologia/métodos , Compostos de Selênio/química , Cádmio/química , Furanos/química , Hexanos/química , Cinética , Ligantes , Microscopia Eletrônica de Transmissão , Compostos Organofosforados/química , Óxidos/química , Semicondutores , Solventes , Temperatura , Fatores de Tempo , Raios Ultravioleta
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA