Search results for "Mesoporou"
showing 10 items of 358 documents
Organic-Inorganic Hybrid Mesoporous Materials as Regenerable Sensing Systems for the Recognition of Nitroaromatic Explosives
2013
[EN] Fluorescent organic-inorganic mesoporous hybrid materials have been prepared and characterised, and their behaviour against nitroaromatic explosives have been tested. MCM-41 silica was used as an inorganic scaffold and pyrene (P derivative containing trialkoxysilane moieties), dansyl and fluorescein (D and F derivatives also containing trialkoxysilane groups, respectively) fluorophores have been anchored on hybrid materials by a co-condensation method to obtain a homogenous distribution of dyes into the pores of the support. Six sensing materials have been prepared, of which SP, SD, SF were hydrophilic and SPh, SDh, SFh were hydrophobic. Template-free hydrophilic materials (SP, SD, SF)…
Modulation of folic acid bioaccessibility by encapsulation in pH-responsive gated mesoporous silica particles
2015
[EN] A study on the controlled release of folic acid (FA) from pH-responsive gated mesoporous silica particles (MSP) is reported. The MCM-41 support was synthesized using tetraethyl orthosilicate (TEOS) as hydrolytic inorganic precursor and the surfactant hexadecyltrimethylammonium bromide (CTAB) as porogen species. Calcination of the mesostructured phase resulted in the starting solid. This solid was loaded with FA to obtain the initial support S0. Moreover, this FA-loaded material was further functionalized with 3-[2-(2-aminoethylamino)ethylamino]propyltrimethoxysilane (N3) in order to obtain the gated polyamine-functionalised material S1. Solids S0 and S1 were characterized using standar…
Protective effect of mesoporous silica particles on encapsulated folates.
2016
Mesoporous silica particles (MSPs) are considered suitable supports to design gated materials for the encapsulation of bioactive molecules. Folates are essential micronutrients which are sensitive to external agents that provoke nutritional deficiencies. Folates encapsulation in MSPs to prevent degradation and to allow their controlled delivery is a promising strategy. Nevertheless, no information exists about the protective effect of MSPs encapsulation to prevent their degradation. In this work, 5-formyltetrahydrofolate (FO) and folic acid (FA) were entrapped in MSPs functionalized with polyamines, which acted as pH-dependent molecular gates. The stability of free and entrapped vitamins af…
Towards chemical communication between gated nanoparticles.
2014
The design of comparatively simple and modularly configurable artificial systems able to communicate through the exchange of chemical messengers is, to the best of our knowledge, an unexplored field. As a proof-of-concept, we present here a family of nanoparticles that have been designed to communicate with one another in a hierarchical manner. The concept involves the use of capped mesoporous silica supports in which the messenger delivered by a first type of gated nanoparticle is used to open a second type of nanoparticle, which delivers another messenger that opens a third group of gated nanoobjects.We believe that the conceptual idea that nanodevices can be designed to communicate with …
Hydrolysis of DCNP (a Tabun mimic) catalyzed by mesoporous silica nanoparticles
2015
[EN] The hydrolysis of diethylcyanophosphonate, DCNP (a Tabun simulant) in the presence of mesoporous silica nanoparticles (MSN) has been studied in acetonitrile:water (99.5:0.5 v/v) mixtures using 31P NMR as a suitable technique to follow the DCNP hydrolysis. MSN alone was not capable to induce DCNP hydrolysis, yet MSN in combination with the presence of the bases potassium carbonate, triethylamine or DABCO enhanced DCNP degradation. When MSN was used combined with K2CO3, a hydrolysis of ca. 95% of the initial DCNP after 60 min was observed. In the presence of DABCO, MSN was able to induce the hydrolysis of ca. 90% of DCNP after the same time. However, the DCNP hydrolysis using MSN in the …
Chromo-Fluorogenic Detection of Nitroaromatic Explosives by Using Silica Mesoporous Supports Gated with Tetrathiafulvalene Derivatives
2013
[EN] Three new hybrid gated mesoporous materials (SN3-1, SNH2-2, and SN3-3) loaded with the dye [Ru(bipy)(3)](2+) (bipy=bipyridine) and capped with different tetrathiafulvalene (TTF) derivatives (having different sizes and shapes and incorporating different numbers of sulfur atoms) have been prepared. The materials SN3-1 and SN3-3 are functionalized on their external surfaces with the TTF derivatives 1 and 3, respectively, which were attached by employing the click chemistry reaction, whereas SNH2-2 incorporates the TTF derivative 2, which was anchored to the solid through an amidation reaction. The final gated materials have been characterized by standard techniques. Suspensions of these s…
Enhanced antifungal efficacy of tebuconazole using gated pH-driven mesoporous nanoparticles
2014
Núria Mas,1–3 Irene Galiana,3 Silvia Hurtado,† Laura Mondragón,1–3 Andrea Bernardos,1–3 Félix Sancenón,1–3 María D Marcos,1–3 Pedro Amorós,4 Nuria Abril-Utrillas,5 Ramón Martínez-Máñez,1–3 José Ramón Murguía1,3 1Centro de Reconocimiento Molecular y Desarrollo Tecnológico (IDM), Centro Mixto Universidad Politécnica de Valencia, Universidad de Valencia, Valencia, Spain; 2Departamento de Química, Universidad Politécnica de Valencia, Valenci…
Amidase-responsive controlled release of antitumoral drug into intracellular media using gluconamide-capped mesoporous silica nanoparticles
2012
MCM-41 silica nanoparticles were used as inorganic scaffolding to prepare a nanoscopic-capped hybrid material S1, which was able to release an entrapped cargo in the presence of certain enzymes, whereas in the absence of enzymes, a zero release system was obtained. S1 was prepared by loading nanoparticles with Safranine O dye and was then capped with a gluconamide derivative. In the absence of enzymes, the release of the dye from the aqueous suspensions of S1 was inhibited as a result of the steric hindrance imposed by the bulky gluconamide derivative, the polymerized gluconamide layer and the formation of a dense hydrogen-bonded network around the pore outlets. Upon the addition of amidase…
Tetrathiafulvalene-Capped Hybrid Materials for the Optical Detection of Explosives
2013
[EN] Mesoporous silica microparticles capped with TTF moieties and containing a ruthenium dye in the pores were used for the turn-on optical detection of the nitroaromatic explosives Tetryl and TNT via a selective pore uncapping and release of the entrapped dye.
Ceramic foam supported active materials for boron remediation in water
2015
Due to the narrowrange between boron necessities and toxicity in the environment, there is a high interest in the design of effective boron remediation procedures. We have previously reported a promising boron adsorptionmaterial based on the affinity of boron aqueous species for cis-diol groups that were anchored on differentmesoporous silica matrices.However, the small particle size of these systemsmakes themdifficult to be applied on real remediation situations. In this context we report herein a novel systemfor boron adsorption fromaqueous solutions inwhich the high boron affinity for functionalized mesoporousmaterials is combined with themechanical properties of ceramic foams as macrosc…