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1.
Data Brief ; 27: 104709, 2019 Dec.
Article de Anglais | MEDLINE | ID: mdl-31737758

RÉSUMÉ

In this work are presented all the conditions of synthesis explored to obtain a new family of compound with formula [Ln(4-OHBBA)3(H2O)2] (Ln = La, Pr). Powder X ray diffraction was used to identify the different phases obtained in the synthetic study. FT-IR spectroscopy and TG analysis for La and Pr pure phases are also reported. Optical properties of optically active CPs materials, solid state photoluminescence properties of La, Pr, La-(5%Eu) and La-(5%Tb) compounds were explored. We report the absorption, excitation and emission spectrum of the 4'-hydroxi-4-biphenylcarboxylic acid and a comparative description of the radiative (and no-radiative) processes in solid state in Ln-(4-OHBBA) and Ln-BPDC compounds. Finally, a principal component analysis was conducted in order to take in account both signal contributions from the sensor (LCE at 384 nm and the europium emission at 610 nm) and for classifying the type of analytes used to test the sensing response of the materials.

2.
Dalton Trans ; 47(6): 1808-1818, 2018 Feb 06.
Article de Anglais | MEDLINE | ID: mdl-29322149

RÉSUMÉ

Main group element coordination polymers (MGE-CPs) are important compounds for the development of multifunctional materials. However, there has been a shortage of studies regarding their structural, optical, catalytic, mechanical, and antibacterial properties. This work presents an exhaustive study of a set of crystalline MGE-CPs obtained from bismuth and indium metals and iminodiacetate, 1,2,4,5-benzenetetracarboxylate, and 2,2'-bipyridine as building blocks. An in-depth topological analysis of the networks was carried out. Additionally, nanoindentation studies were performed on two representative low-dimensional compounds in order to find the relationships between their structural features and their intrinsic mechanical properties (hardness and elasticity). The solid-state photoluminescence (SSPL) properties were also studied in terms of excitation, emission, lifetimes values, and CIE chromaticites. Moreover, the heterogeneous catalytic activities of the compounds were evaluated with the cyanosilylation reaction using a set of carbonylic substrates under solvent-free conditions. Finally, the inhibitory effect of the Bi-CPs on the growth of microorganisms such as Escherichia coli, Salmonella enterica serovar Typhimurium, and Pseudomonas aeruginosa, which are associated with relevant infectious diseases, is reported.

3.
Nanoscale ; 5(20): 9690-8, 2013 Oct 21.
Article de Anglais | MEDLINE | ID: mdl-23969526

RÉSUMÉ

We report the first nanoformulation of Hyaluronidase (Hyal) and its enhanced adjuvant effect over the free enzyme. Hyaluronic acid (HA) degrading enzyme Hyal was immobilized on 250 nm silica nanoparticles (SiNP) maintaining specific activity of the enzyme via the layer-by-layer self-assembly technique. This process was characterized by dynamic light scattering (DLS), zeta potential, infrared and UV-Vis spectroscopy, transmission electron microscopy (TEM) and enzymatic activity measurements. The nanoparticles were tested in vivo as adjuvants of carboplatin (CP), peritumorally injected in A375 human melanoma bearing mice and compared with the non-immobilized enzyme, on the basis of equal enzymatic activity. Alcian Blue staining of A375 tumors indicated large overexpression of hyaluronan. At the end of the experiment, tumor volume reduction with SiNP-immobilized Hyal was significantly enhanced compared to non-immobilized Hyal. Field emission scanning electron microscopy (FE-SEM) images together with energy dispersive X-ray spectroscopy (EDS) spectra confirmed the presence of SiNP on the tumor. We mean a proof of concept: this extracellular matrix (ECM) degrading enzyme, immobilized on SiNP, is a more effective local adjuvant of cancer drugs than the non-immobilized enzyme. This could prove useful in future therapies using other or a combination of ECM degrading enzymes.


Sujet(s)
Antinéoplasiques/administration et posologie , Carboplatine/administration et posologie , Acide hyaluronique/métabolisme , Mélanome/traitement médicamenteux , Nanoparticules/composition chimique , Silice/composition chimique , Tumeurs cutanées/traitement médicamenteux , Animaux , Vecteurs de médicaments/composition chimique , Enzymes immobilisées/composition chimique , Enzymes immobilisées/métabolisme , Femelle , Humains , Hyaluronoglucosaminidase/composition chimique , Hyaluronoglucosaminidase/métabolisme , Mélanome/anatomopathologie , Souris , Souris nude , Porosité , Tumeurs cutanées/anatomopathologie , Transplantation hétérologue
4.
J Hazard Mater ; 223-224: 53-62, 2012 Jul 15.
Article de Anglais | MEDLINE | ID: mdl-22595542

RÉSUMÉ

Hybrid mesoporous materials are potentially useful for metal ion scavenging and retrieval because of their high surface areas, controlled accessibility and tailored functionalization. Some aspects that are linked to the performance of HMM include pore accessibility, stability of the organic functions and reusability. Knowledge of these aspects is critical in the design of adsorption-desorption protocols. In this work we produce and characterize propylamino-substituted large pore silica (SBA-15-N), which is submitted to Cu(II) adsorption from copper sulfate solutions, followed by desorption in acid media and material regeneration. We find that the hybrid material is an efficient adsorbent (1.15-1.75mmol Cu(II)g(-1)), although a fraction of the organic groups is lost during the adsorption process. An X-ray photoelectron spectroscopy (XPS) study demonstrates that the contents of amino groups are higher in the material surface, leading to different behaviors in Cu(II) complexation along the material. These materials can be regenerated by exposure to acidic media. Thermal processing of the hybrid materials leads to better durability in aqueous solutions during reprocessing, due to enhanced polycondensation of the inorganic framework. Thermally treated samples, once regenerated, are efficient adsorbents in a second step of Cu(II) adsorption. We discuss the materials processing factors involved in the improved adsorption of Cu(II), its quantitative release and reusability of the material.


Sujet(s)
Sulfate de cuivre/isolement et purification , Propylamines/composition chimique , Recyclage , Silice/composition chimique , Polluants chimiques de l'eau/isolement et purification , Purification de l'eau/méthodes , Adsorption , Microscopie électronique à balayage , Spectroscopie photoélectronique , Porosité , Spectroscopie infrarouge à transformée de Fourier , Propriétés de surface
5.
Small ; 5(2): 272-80, 2009 Feb.
Article de Anglais | MEDLINE | ID: mdl-19115355

RÉSUMÉ

Silver nanoparticle assemblies are embedded within mesoporous oxide thin films by an in situ mild reduction leading to nanoparticle-mesoporous oxide thin-film composites (NP@MOTF). A quantitative method based on X-ray reflectivity is developed and validated with energy dispersive spectroscopy in order to assess pore filling. The use of dilute formaldehyde solutions leads to control over the formation of silver nanoparticles within mesoporous titania films. Inclusion of silver nanoparticles in mesoporous silica requires more drastic conditions. This difference in reactivity can be exploited to selectively synthesize nanoparticles in a predetermined layer of a multilayered mesoporous stack leading to complex 1D-ordered multilayers with precise spatial location of nanometric objects. The metal oxide nanocomposites synthesized have potential applications in catalysis, optical devices, surface-enhanced Raman scattering, and metal enhancement fluorescence.


Sujet(s)
Nanoparticules métalliques/composition chimique , Nanotechnologie/méthodes , Argent/composition chimique , Métaux/composition chimique , Microscopie électronique à transmission , Nanoparticules/composition chimique , Optique et photonique , Oxydes/composition chimique , Silice/composition chimique , Spectrométrie de fluorescence/méthodes , Analyse spectrale Raman/méthodes , Propriétés de surface , Titane/composition chimique , Rayons X
6.
Chemistry ; 12(17): 4478-94, 2006 Jun 02.
Article de Anglais | MEDLINE | ID: mdl-16429466

RÉSUMÉ

Mesoporous films containing organic or biological functions within an organised array of cavities are produced by combining sol-gel, self-assembly of supramolecular templates and surface chemistry. This paper reviews the essential physics and chemical concepts behind the synthesis of these complex multifunctional materials.


Sujet(s)
Produits biologiques/composition chimique , Produits chimiques inorganiques/composition chimique , Composés chimiques organiques/composition chimique , Polymères/composition chimique , Produits biologiques/synthèse chimique , Produits chimiques inorganiques/synthèse chimique , Composés chimiques organiques/synthèse chimique , Flexibilité , Polymères/synthèse chimique , Porosité , Propriétés de surface
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