149 results on '"M. Dolores Marcos"'
Search Results
2. Surfactant-Triggered Molecular Gate Tested on Different Mesoporous Silica Supports for Gastrointestinal Controlled Delivery
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Elisa Poyatos-Racionero, Isabel González-Álvarez, Marta González-Álvarez, Ramón Martínez-Máñez, M. Dolores Marcos, Andrea Bernardos, and Elena Aznar
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mesoporous silica ,oleic acid ,molecular gate ,MCM-41 ,MCM-48 ,SBA-15 ,Chemistry ,QD1-999 - Abstract
In recent decades, the versatility of mesoporous silica particles and their relevance to develop controlled release systems have been demonstrated. Within them, gated materials able to modulate payload delivery represent great advantages. However, the role played by the porous matrix in this kind of systems is scarce. In this work, different mesoporous silica materials (MCM-41, MCM-48, SBA-15 and UVM-7) are functionalized with oleic acid as a molecular gate. All systems are fully characterized and their ability to confine the entrapped cargo and release it in the presence of bile salts is validated with release assays and in vitro digestion experiments. The cargo release profile of each synthesized support is studied, paying attention to the inorganic scaffold. Obtained release profiles fit to Korsmeyer–Peppas model, which explains the differences among the studied supports. Based on the results, UVM-7 material was the most appropriate system for duodenal delivery and was tested in an in vivo model of the Wistar rat. Payload confinement and its complete release after gastric emptying is achieved, establishing the possible use of mesoporous silica particles as protection and direct release agents into the duodenum and, hence, demonstrating that these systems could serve as an alternative to the administration methods employed until now.
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- 2020
- Full Text
- View/download PDF
3. Gold Nanoparticle-Assisted Virus Formation by Means of the Delivery of an Oncolytic Adenovirus Genome
- Author
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Luis Sendra, Antonio Miguel, M. Carmen Navarro-Plaza, María José Herrero, José de la Higuera, Consuelo Cháfer-Pericás, Elena Aznar, M. Dolores Marcos, Ramón Martínez-Máñez, Luis Alfonso Rojas, Ramón Alemany, and Salvador F. Aliño
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gold nanoparticles ,delivery ,gene therapy ,non-viral vectors ,oncolytic virus ,virotherapy ,Chemistry ,QD1-999 - Abstract
Oncolytic adenoviruses are a therapeutic alternative to treat cancer based on their ability to replicate selectively in tumor cells. However, their use is limited mainly by the neutralizing antibody (Nab) immune response that prevents repeated dosing. An alternative to facilitate the DNA access to the tumor even in the presence of anti-viral Nabs could be gold nanoparticles able to transfer DNA molecules. However, the ability of these nanoparticles to carry large DNA molecules, such as an oncolytic adenovirus genome, has not been studied. In this work, gold nanoparticles were functionalized with different amounts of polyethylenimine to transfer in a safe and efficient manner a large oncolytic virus genome. Their transfer efficacy and final effect of the oncolytic virus in cancer cells are studied. For each synthesized nanoparticle, (a) DNA loading capacity, (b) complex size, (c) DNA protection ability, (d) transfection efficacy and (e) cytotoxic effect were studied. We observed that small gold nanoparticles (70–80 nm in diameter) protected DNA against nucleases and were able to transfect the ICOVIR-15 oncolytic virus genome encoded in pLR1 plasmid. In the present work, efficient transgene RNA expression, luciferase activity and viral cytopathic effect on cancer cells are reported. These results suggest gold nanoparticles to be an efficient and safe vector for oncolytic adenovirus genome transfer.
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- 2020
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4. Precatalyst or dosing-device? The [Pd2{μ-(C6H4) PPh2}2{μ-O2C(C6H5)}2] complex anchored on a carboxypolystyrene polymer as an effective supplier of palladium catalytically active nanoparticles for the Suzuki-Miyaura reaction
- Author
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M. Angeles Ubeda, Pedro Amorós, Francisco Pérez-Pla, Juan F. Sánchez-Royo, Jamal El Haskouri, and M. Dolores Marcos
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inorganic chemicals ,chemistry.chemical_classification ,010405 organic chemistry ,Nanoparticle ,chemistry.chemical_element ,Polymer ,Mesoporous silica ,010402 general chemistry ,01 natural sciences ,Catalysis ,0104 chemical sciences ,chemistry ,X-ray photoelectron spectroscopy ,Chemical engineering ,Catalytic cycle ,Oxidation state ,Physical and Theoretical Chemistry ,Palladium - Abstract
A new catalyst has been synthesized from the precursor [Pd2{μ-(C6H4) PPh2}2 {μ-O2C(C6H5)}2] immobilized on a carboxypolystyrene polymer that exhibits an excellent dispersion of the Pd (II) centers, reusability, and catalytic activity in front of phenyl bromides. The activity of this new material was studied in detail for the Suzuki-Miyaura reaction and compared to that of Pd nanoparticles (NPs) supported on UVM-7 (a mesoporous silica), and Pd NPs stabilized with polyvinylpirrolydone. The homogeneous/heterogeneous character of the catalytic process was determined from the results of the hot-filtration, centrifugation, poisoning, three phases tests, and from differential sensitivity kinetic assays. Changes in the palladium oxidation state, and the size and morphology of the Pd NPs formed during several reusing catalytic cycles were determined by XPS, and by SEM and STEM-HAADF respectively. Kinetic and structural analyses concluded that the new material behaved as a supplier of active Pd(0) NPs to the Suzuki-Miyaura catalytic cycle, which was determined to be driven mainly by the palladium fraction present in solution.
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- 2020
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- View/download PDF
5. Generalized 'one-pot' preparative strategy to obtain highly functionalized silica-based mesoporous spherical particles
- Author
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M. Dolores Garrido, Jamal El Haskouri, David Vie, Aurelio Beltrán, José Vicente Ros-Lis, M. Dolores Marcos, Nicolás Moliner, and Pedro Amorós
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Mechanics of Materials ,one-pot synthesis ,functionalization ,General Materials Science ,General Chemistry ,mesoporous silica ,UNESCO::CIENCIAS TECNOLÓGICAS ,Condensed Matter Physics ,size modulation ,spherical particles - Abstract
In this work we present a synthesis strategy for the preparation of Stöber-type mesoporous particles functionalized with inorganic species. The procedure is based on a combination of the Atrane and the Stöber methods. Both as a source of silicon and of the incorporated heteroelements (Fe, Zn, Al, Ti) the corresponding atrane complexes are used as hydrolytic reagents. These complexes are easily formed by reaction with triethanolamine. Mesoporosity is achieved using surfactant micelles as templates. Obtaining uniform spherical particles is achieved by optimizing the amount of water-ethanol in the reaction medium. The particle sizes have been modulated by controlling simple parameters such as reaction time or temperature. The incorporation of inorganic species is on many occasions incompatible with the preservation of spherical morphology, resulting in heterogeneous particles in shape and size and even phase segregation for high functionalization degrees. The methodology that we propose makes it possible to achieve a high concentration of highly dispersed heteroelements (even at molecular level), maintaining, to a large extent, both sphericity and particle size homogeneity. The Si/M molar ratios achieved are significantly lower (greater functionalization) than those usually reported in the literature. The strategy is generalizable for the incorporation of a great variety of elements, and specially for first row transition elements.
- Published
- 2022
6. Dualplex lateral flow assay for simultaneous scopolamine and 'cannibal drug' detection based on receptor-gated mesoporous nanoparticles
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Eva Garrido, Estela Climent, M. Dolores Marcos, Félix Sancenón, Knut Rurack, and Ramón Martínez-Máñez
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QUIMICA ORGANICA ,Scopolamine ,QUIMICA INORGANICA ,Humans ,Nanoparticles ,General Materials Science ,Bethanechol ,Silicon Dioxide ,Nanostructures - Abstract
[EN] We report herein the design of a strip-based rapid test utilizing bio-inspired hybrid nanomaterials for the in situ and at site detection of the drug scopolamine (SCP) using a smartphone for readout, allowing SCP identification in diluted saliva down to 40 nM in less than 15 min. For this purpose, we prepared a nanosensor based on mesoporous silica nanoparticles loaded with a fluorescent reporter (rhodamine B) and functionalized with bethanechol, a potent agonist of recombinant human muscarinic acetylcholine receptor M-2 (M-2-AChR). M-2-AChR interaction with the anchored bethanechol derivative leads to capping of the pores. The sensing mechanism relies on binding of SCP to M-2-AChR resulting in pore opening and delivery of the entrapped rhodamine B reporter. Moreover, the material was incorporated into strips for lateral-flow assays coupled to smartphone readout, giving fast response time, good selectivity, and exceptional sensitivity. In an attempt to a mobile analytical test system for law enforcement services, we have also developed a dualplex lateral flow assay for SCP and 3,4-methylenedioxypyrovalerone (MDPV) also known as the so-called "cannibal drug"., This research was funded by the Ministerio de Ciencia, Innovacion y Universidades (Spanish Government), the Agencia Estatal de Investigacion (AEI), the European Union (projects RTI2018-100910-B-C41 and RTI2018-101599-B-C22-AR (MCIU/AEI/FEDER, EU), the Conselleria de Innovacion, Universidades, Ciencia y Sociedad Digital, Generalitat Valenciana (Project PROMETEO 2018/024) and the German Research Foundation (DFG; CL 761/1-19). E. G. is grateful to the Spanish MEC for her FPU grant (FPU16/02464).
- Published
- 2022
7. High content and dispersion of Gd in bimodal porous silica: T2 contrast agents under ultra-high magnetic fields
- Author
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M. Dolores Garrido, Nuria Puchol, Jamal El Haskouri, Juan Francisco Sánchez-Royo, José Vicente Folgado, Vannina Gonzalez Marrachelli, Itziar Pérez Terol, José Vicente Ros-Lis, M. Dolores Marcos, Rafael Ruíz, Aurelio Beltrán, José Manuel Morales, and Pedro Amorós
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magnetic resonance microscopy ,Mechanics of Materials ,silica ,General Materials Science ,General Chemistry ,gadolinium ,UNESCO::CIENCIAS TECNOLÓGICAS ,Condensed Matter Physics ,mesoporous ,magnetic resonance image - Abstract
Silica-based UVM-7-type bimodal mesoporous materials with high gadolinium content (∞ ≥ Si/Gd ≥ 13) have been synthesized through a one-pot surfactant-assisted procedure from hydroalcoholic solution using a cationic surfactant as template, and starting from atrane complexes of Gd and Si as inorganic precursors. The novel synthetic pathway developed in the study preserves the UVM-7-type architecture while optimizing the dispersion of the Gd-guest species at the nanoscale and even at atomic level. It has been determined that the number of Gd atoms forming clusters is always less than 10. The behaviour under exposure to ultra-high magnetic fields reveals a significant increase in the transversal relaxivity value when compared with related materials in the bibliography. Their activity as T2 instead of T1 contrast agents is discussed and explained considering the high Gd-dispersion and concentration, nature of the materials as well as due to the high magnetic fields used, typical of MRM studies. The absence of toxicity has been confirmed in preliminary cell cultures “in vitro” and the degradation of the solids studied under biological conditions. Results suggest that the atrane route could be a suitable synthesis approach for the preparation of Gd containing contrast agents.
- Published
- 2022
8. Strip-based lateral flow-type indicator displacement assay for γ-hydroxybutyric acid (GHB) detection in beverages
- Author
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Eva Garrido, Guillermo Hernández-Sigüenza, Estela Climent, M. Dolores Marcos, Knut Rurack, Pablo Gaviña, Margarita Parra, Félix Sancenón, Vicente Martí-Centelles, and Ramón Martínez-Máñez
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Materials Chemistry ,Metals and Alloys ,Electrical and Electronic Engineering ,Condensed Matter Physics ,Instrumentation ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials - Published
- 2023
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9. Biocompatibility and internalization assessment of bare and functionalised mesoporous silica nanoparticles
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Pilar Eroles, M. Dolores Marcos, Guadalupe Herrera, Iris Garrido-Cano, Ramón Martínez-Máñez, Juan Miguel Cejalvo, Ana Lluch, Félix Sancenón, and Vicente Candela-Noguera
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Membrane potential ,Biocompatibility ,Toxicity ,media_common.quotation_subject ,Mesoporous silica nanoparticles ,QUIMICA INORGANICA ,Nanoparticle ,General Chemistry ,Polyethylene glycol ,Mesoporous silica ,Condensed Matter Physics ,Endocytosis ,chemistry.chemical_compound ,QUIMICA ORGANICA ,chemistry ,Mechanics of Materials ,Hyaluronic acid ,BIOQUIMICA Y BIOLOGIA MOLECULAR ,Biophysics ,General Materials Science ,Internalization ,media_common - Abstract
[EN] We report herein an evaluation of the effect of several mesoporous silica nanoparticles (MSNs) on the cellular uptake and in vitro cytotoxicity in human cells. Bare MSNs and MSNs functionalized with polyethylene glycol or hyaluronic acid are employed to evaluate uptake efficiency and mechanisms of endocytosis in cancer (MDA-MB-231) and non-cancer (MCF10A) cells. Moreover, changes in viability, cell cycle, oxidative stress, and mitochondrial membrane potential are evaluated. Our results confirm that MSNs are internalized efficiently by human cells and that uptake mechanisms differ for cell types and particles. We also confirm that MSNs are biocompatible materials that do not induce ROS/RNS production, nor changes on mitochondrial membrane potential or cell cycle., The authors want to thank the Spanish Government RTI2018-100910-B-C41 (MCUI/AEI/FEDER, UE) and PI18/01219 (ISCIII), the Generalitat Valenciana (PROMETEO/2018/024 and ACIF/2016/030), and CIBER-BBN (CB07/01/2012) and CIBER-ONC (CB16/12/00481) for support.
- Published
- 2021
10. Nanoparticle-cell-nanoparticle communication by stigmergy to enhance poly(I:C) induced apoptosis in cancer cells
- Author
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Félix Sancenón, José Ramón Murguía, Carmen Coll, Elena Aznar, Ramón Martínez-Máñez, M. Dolores Marcos, Cristina Giménez, Amelia Ultimo, and Cristina de la Torre
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Interferon Inducers ,Cell ,Sulforhodamine B ,Nanoparticle ,Antineoplastic Agents ,Apoptosis ,Cell Communication ,010402 general chemistry ,01 natural sciences ,Catalysis ,Interferon-gamma ,chemistry.chemical_compound ,QUIMICA ORGANICA ,Cell Line, Tumor ,CIENCIA DE LOS MATERIALES E INGENIERIA METALURGICA ,QUIMICA ANALITICA ,Materials Chemistry ,medicine ,BIOQUIMICA Y BIOLOGIA MOLECULAR ,Humans ,Receptor ,Alitretinoin ,Rhodamines ,010405 organic chemistry ,QUIMICA INORGANICA ,Metals and Alloys ,General Chemistry ,Molecular biology ,Toll-Like Receptor 3 ,0104 chemical sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Poly I-C ,medicine.anatomical_structure ,Cell killing ,Gene Expression Regulation ,chemistry ,Cancer cell ,TLR3 ,Ceramics and Composites ,Nanoparticles - Abstract
[EN] Nanoparticle-cell-nanoparticle communication by stigmergy was demonstrated using two capped nanodevices. The first community of nanoparticles (i.e.S(RA)(IFN)) is loaded with 9-cis-retinoic acid and capped with interferon-gamma, whereas the second community of nanoparticles (i.e.S(sulf)(PIC)) is loaded with sulforhodamine B and capped with poly(I:C). The uptake ofS(RA)(IFN)by SK-BR-3 breast cancer cells enhanced the expression of TLR3 receptor facilitating the subsequent uptake ofS(sulf)(PIC)and cell killing., We thank the Spanish Government (projects RTI2018-100910-B-C41 and RTI2018-101599-B-C22 (MCUI/FEDER, EU)), Generalitat Valenciana (project PROMETEO2018/024) and CIBER-BBN (project NANOCOMMUNITY) for support. A. U. and C. G are grateful to the Ministry of Education, Culture and Sport for her doctoral FPU grant.
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- 2020
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11. Gold Nanoparticle-Assisted Virus Formation by Means of the Delivery of an Oncolytic Adenovirus Genome
- Author
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M. Dolores Marcos, Antonio Miguel, Ramon Alemany, Ramón Martínez-Máñez, Consuelo Cháfer-Pericás, Luis Sendra, Salvador F. Aliño, Luis A. Rojas, José de la Higuera, María José Herrero, Elena Aznar, and M Carmen Navarro-Plaza
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Oncolytic adenovirus ,Virus oncogènics ,Oncolytic virus ,viruses ,General Chemical Engineering ,Genetic enhancement ,02 engineering and technology ,Article ,Virus ,lcsh:Chemistry ,Nanofluids ,03 medical and health sciences ,chemistry.chemical_compound ,Gene therapy ,Plasmid ,CIENCIA DE LOS MATERIALES E INGENIERIA METALURGICA ,non-viral vectors ,Gold nanoparticles ,cancer ,General Materials Science ,Virotherapy ,Càncer ,Cancer ,030304 developmental biology ,oncolytic virus ,0303 health sciences ,Oncogenic viruses ,QUIMICA INORGANICA ,Transfection ,021001 nanoscience & nanotechnology ,Virology ,gene therapy ,lcsh:QD1-999 ,chemistry ,gold nanoparticles ,Non-viral vectors ,delivery ,virotherapy ,0210 nano-technology ,Delivery ,DNA - Abstract
[EN] Oncolytic adenoviruses are a therapeutic alternative to treat cancer based on their ability to replicate selectively in tumor cells. However, their use is limited mainly by the neutralizing antibody (Nab) immune response that prevents repeated dosing. An alternative to facilitate the DNA access to the tumor even in the presence of anti-viral Nabs could be gold nanoparticles able to transfer DNA molecules. However, the ability of these nanoparticles to carry large DNA molecules, such as an oncolytic adenovirus genome, has not been studied. In this work, gold nanoparticles were functionalized with different amounts of polyethylenimine to transfer in a safe and efficient manner a large oncolytic virus genome. Their transfer efficacy and final effect of the oncolytic virus in cancer cells are studied. For each synthesized nanoparticle, (a) DNA loading capacity, (b) complex size, (c) DNA protection ability, (d) transfection efficacy and (e) cytotoxic effect were studied. We observed that small gold nanoparticles (70-80 nm in diameter) protected DNA against nucleases and were able to transfect the ICOVIR-15 oncolytic virus genome encoded in pLR1 plasmid. In the present work, efficient transgene RNA expression, luciferase activity and viral cytopathic effect on cancer cells are reported. These results suggest gold nanoparticles to be an efficient and safe vector for oncolytic adenovirus genome transfer., This research was supported by University of Valencia 'Ayuda a la Investigacion', Asociacion Pablo Ugarte and European Regional Development Fund (VLC-CAMPUS).
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- 2020
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12. Lab and Pilot-Scale Synthesis of MxOm@SiC Core–Shell Nanoparticles
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Sarai Pradas, Àngela Ribes, Ramón Martínez-Máñez, Alejandro Cuenca-Bustos, Andy Hernández-Montoto, M. José López-Tendero, Luis A. Villaescusa, Santiago Sánchez-Cabezas, M. Dolores Marcos, and Elena Aznar
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Materials science ,Sol-gel synthesis ,Shell (structure) ,Nanoparticle ,02 engineering and technology ,010402 general chemistry ,lcsh:Technology ,01 natural sciences ,Article ,Matrix (chemical analysis) ,sol–gel synthesis ,Core-shell nanoparticles ,Scanning transmission electron microscopy ,General Materials Science ,Ceramic ,core–shell nanoparticles ,silicon carbide covering ,lcsh:Microscopy ,Nanoscopic scale ,lcsh:QC120-168.85 ,lcsh:QH201-278.5 ,lcsh:T ,QUIMICA INORGANICA ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,Chemical engineering ,lcsh:TA1-2040 ,visual_art ,visual_art.visual_art_medium ,lcsh:Descriptive and experimental mechanics ,lcsh:Electrical engineering. Electronics. Nuclear engineering ,Wetting ,synthesis up-scaling ,lcsh:Engineering (General). Civil engineering (General) ,0210 nano-technology ,Dispersion (chemistry) ,lcsh:TK1-9971 - Abstract
The addition of light ceramic particles to bulk technological materials as reinforcement to improve their mechanical properties has attracted increasing interest in the last years. The metal matrix composites obtained using nanoparticles have been reported to exhibit an improvement of their properties due to the decrease in the size of the ceramic additives to the nanoscale. Additionally, important effects such as the dispersion of the nanoparticles, wettability, and low reactivity can be controlled by the modification of the nanoparticles&rsquo, surface. In this work, we present the preparation of core&ndash, shell MxOm@SiC nanoparticles with different shell compositions. The accurate and reproducible preparation is developed both at the lab and pilot scale. The synthesis of these core&ndash, shell nanoparticles and their scale-up production are fundamental steps for their industrial use as additives in metal matrix composites and alloys. Powder X-ray diffraction and energy dispersive X-ray (EDX) coupled with scanning transmission electron microscopy (STEM) are used to corroborate the formation of the core&ndash, shell systems, whereas line scan-EDX analysis allows measuring the average shell thickness.
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- 2020
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13. Nanosensor for Sensitive Detection of the New Psychedelic Drug 25I-NBOMe
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Ramón Martínez-Máñez, M. Dolores Marcos, Pablo Gaviña, Eva Garrido, Beatriz Lozano-Torres, Borja Díaz de Greñu, Félix Sancenón, Margarita Parra, and María Alfonso
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Serotonin ,Mesoporous silica nanoparticles ,25I-NBOMe ,hallucinogenic drugs ,Mescaline ,sensors ,Catalysis ,chemistry.chemical_compound ,Agonist 5-HT2A serotonin receptor ,QUIMICA ORGANICA ,QUIMICA ANALITICA ,medicine ,Rhodamine B ,Humans ,mesoporous silica nanoparticles ,Nanodevice ,Lysergic acid diethylamide ,Detection limit ,Sensors ,QUIMICA INORGANICA ,Organic Chemistry ,MDMA ,General Chemistry ,Mesoporous silica ,Hallucinogenic drugs ,Combinatorial chemistry ,chemistry ,Dimethoxyphenylethylamine ,25I-NBOMe, agonist 5-HT2A serotonin receptor, hallucinogenic drugs, mesoporous silica nanoparticles, sensors ,Hallucinogens ,agonist 5-HT2A serotonin receptor ,medicine.drug - Abstract
[EN] This work reports the synthesis, characterization, and sensing behavior of a hybrid nanodevice for the detection of the potent abuse drug 25I-NBOMe. The system is based on mesoporous silica nanoparticles, loaded with a fluorescent dye, functionalized with a serotonin derivative and capped with the 5-HT2A receptor antibody. In the presence of 25I-NBOMe the capping antibody is displaced, leading to pore opening and rhodamine B release. This delivery was ascribed to 5-HT2A receptor antibody detachment from the surface due to its stronger coordination with 25I-NBOMe present in the solution. The prepared nanodevice allowed the sensitive (limit of detection of 0.6 mm) and selective recognition of the 25I-NBOMe drug (cocaine, heroin, mescaline, lysergic acid diethylamide, MDMA, and morphine were unable to induce pore opening and rhodamine B release). This nanodevice acts as a highly sensitive and selective fluorometric probe for the 25I-NBOMe illicit drug in artificial saliva and in sweets., The authors thank the Spanish Government (projects RTI2018-100910-B-C41 (MCUI/AEI/FEDER, UE) and CTQ2017-87954-P) and the Generalitat Valencia (PROMETEO/2018/024) for support. E.G. is grateful to the Spanish MEC for her FPU grant. The authors also thank the Electron Microscopy Service at the UPV for support.
- Published
- 2020
14. Surfactant-Triggered Molecular Gate Tested on Different Mesoporous Silica Supports for Gastrointestinal Controlled Delivery
- Author
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Andrea Bernardos, Isabel González-Álvarez, Elisa Poyatos-Racionero, Ramón Martínez-Máñez, M. Dolores Marcos, Marta González-Álvarez, and Elena Aznar
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Scaffold ,General Chemical Engineering ,UVM-7 ,Gastrointestinal delivery ,Molecular gate ,MCM-41 ,Article ,lcsh:Chemistry ,Kinetic modelling ,Pulmonary surfactant ,In vivo ,Controlled delivery ,CIENCIA DE LOS MATERIALES E INGENIERIA METALURGICA ,QUIMICA ANALITICA ,Controlled release ,General Materials Science ,mesoporous silica ,Gastric emptying ,Chemistry ,molecular gate ,QUIMICA INORGANICA ,Mesoporous silica ,Oleic acid ,SBA-15 ,Chemical engineering ,lcsh:QD1-999 ,oleic acid ,MCM-48 ,kinetic modelling ,controlled release ,gastrointestinal delivery - Abstract
[EN] In recent decades, the versatility of mesoporous silica particles and their relevance to develop controlled release systems have been demonstrated. Within them, gated materials able to modulate payload delivery represent great advantages. However, the role played by the porous matrix in this kind of systems is scarce. In this work, different mesoporous silica materials (MCM-41, MCM-48, SBA-15 and UVM-7) are functionalized with oleic acid as a molecular gate. All systems are fully characterized and their ability to confine the entrapped cargo and release it in the presence of bile salts is validated with release assays and in vitro digestion experiments. The cargo release profile of each synthesized support is studied, paying attention to the inorganic scaffold. Obtained release profiles fit to Korsmeyer-Peppas model, which explains the differences among the studied supports. Based on the results, UVM-7 material was the most appropriate system for duodenal delivery and was tested in an in vivo model of the Wistar rat. Payload confinement and its complete release after gastric emptying is achieved, establishing the possible use of mesoporous silica particles as protection and direct release agents into the duodenum and, hence, demonstrating that these systems could serve as an alternative to the administration methods employed until now., This research was funded by the Spanish Government (projects RTI2018-100910-B-C41 and RTI2018-101599-B-C22-AR (MCUI/FEDER, EU)) and the Generalitat Valenciana (project PROMETEO/2018/024 and ACIF/2016/023 grant).
- Published
- 2020
15. A new efficient, highly dispersed, Pd nanoparticulate silica supported catalyst synthesized from an organometallic precursor. Study of the homogeneous vs. heterogeneous activity in the Suzuki-Miyaura reaction
- Author
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M. Angeles Ubeda, Jamal El Haskouri, M. Dolores Marcos, Pedro Alfonso Albiñana, Francisco Pérez-Pla, Francisco Estevan, and Pedro Amorós
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UVM-7 silica ,Heterogeneous homogeneous catalysis ,chemistry.chemical_element ,010402 general chemistry ,Heterogeneous catalysis ,HRTEM, XRD ,01 natural sciences ,Catalysis ,Nanoclusters ,Suzuki-Miyaura ,chemistry.chemical_compound ,Physical and Theoretical Chemistry ,Phenylboronic acid ,High-resolution transmission electron microscopy ,STEM-HAADF ,010405 organic chemistry ,QUIMICA INORGANICA ,Mesoporous silica ,Palladium nanoparticles ,0104 chemical sciences ,Kinetic study ,chemistry ,Chemical engineering ,Selectivity ,Palladium - Abstract
[EN] A new Pd(0) catalyst supported on silica UVM-7 has been synthesized from the organometallic [Pd-2(mu-(C6H4) Pp(2))(2)(CH3CN)(4)](BF4)(2) precursor, characterized by the high dispersion, activity, and small size of the palladium nanoclusters fixed on the silica surface. The catalyst was tested for the Suzuki-Miyaura (SM) reaction of different 4-substitutedphenyl halides with phenylboronic acid. The kinetic study concurs with most of the catalytic action was carried out by Pd species originated by the partial solubilization of Pd immobilized on mesoporous silica. The Schmidt's analysis of differential selectivity (SADS) in several competitive SM reactions, together the STEM-HAADF and HRTEM images of the catalyst surface taken along several reuse cycles support the conclusions of the kinetic study. Furthermore, this hypothesis was critically investigated using different classic approaches to distinguish between homogeneous and heterogeneous catalysis as the three phases test, poisoning, and hot filtrate experiments. (C) 2018 Elsevier Inc. All rights reserved., We thank the Spanish Ministerio de Economía y Competitividad and European Feder Funds (MAT2015-64139-C4-2-R) for funding this research.
- Published
- 2018
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16. Fluorogenic Sensing of Carcinogenic Bisphenol A using Aptamer-Capped Mesoporous Silica Nanoparticles
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Andrea Bernardos, Pedro Amorós, Ramón Martínez-Máñez, M. Dolores Marcos, Àngela Ribes, Félix Sancenón, and Elena Aznar
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INGENIERIA DE LA CONSTRUCCION ,endocrine system ,Bisphenol A ,Aptamer ,Mesoporous silica nanoparticles ,Nanoparticle ,02 engineering and technology ,010402 general chemistry ,Electron Microscopy Service of the UPV ,01 natural sciences ,Catalysis ,chemistry.chemical_compound ,QUIMICA ORGANICA ,QUIMICA ANALITICA ,Rhodamine B ,Organic chemistry ,reproductive and urinary physiology ,Carcinogen ,Detection limit ,urogenital system ,Gated nanomaterials ,QUIMICA INORGANICA ,Organic Chemistry ,General Chemistry ,Mesoporous silica ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,Bisphenol a ,Fluorogenic sensing ,chemistry ,0210 nano-technology ,hormones, hormone substitutes, and hormone antagonists ,Nuclear chemistry - Abstract
[EN] Mesoporous silica nanoparticles loaded with rhodamine B and capped with a bisphenol A aptamer were used for the selective and sensitive detection of this lethal chemical. The pores of the nanoparticles are selectively opened in the presence of bisphenol A (through its selective coordination with the aptamer) with subsequent rhodamine B delivery. With this capped material a limit of detection as low as 3.5 mu m of bisphenol A was measured., We thank the Spanish Government (projects MAT2015-64139-C4-1-R and AGL2015-70235-C2-2-R (MINECO/FEDER)) and the Generalitat Valenciana (project PROMETEOII/2014/047) for support. A.R. thanks UPV for her predoctoral fellowship. A.B. thanks the Spanish Government for the finantial support "Juan de la Cierva-Incorporacion" (IJCI-2014-21534). The authors also thank the Electron Microscopy Service at the UPV for support.
- Published
- 2017
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17. A Versatile New Paradigm for the Design of Optical Nanosensors Based on Enzyme-Mediated Detachment of Labeled Reporters: The Example of Urea Detection
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Antoni Llopis-Lorente, M. Dolores Marcos, Ramón Martínez-Máñez, Reynaldo Villalonga, and Félix Sancenón
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chromo-fluorogenic probes ,Urease ,Janus particles ,010402 general chemistry ,01 natural sciences ,Catalysis ,Urea sensing ,chemistry.chemical_compound ,QUIMICA ORGANICA ,Nanosensor ,QUIMICA ANALITICA ,Nanotechnology ,Nanodevice ,biology ,nanotechnology ,010405 organic chemistry ,Chemistry ,Oligonucleotide ,Organic Chemistry ,QUIMICA INORGANICA ,General Chemistry ,biosensors ,Combinatorial chemistry ,0104 chemical sciences ,Nanosensors ,Biosensors ,Nanoarchitectonics ,biology.protein ,Urea ,Chromo-fluorogenic probes ,Biosensor ,nanosensors ,urea sensing - Abstract
[EN] Here, a new bio-inspired nanoarchitectonics approach for the design of optical probes is presented. It is based on nanodevices that combine 1) an enzymatic receptor subunit, 2) a signaling subunit (consisting of a labeled reporter attached to a silica surface), and 3) a mechanism of communication between the two sites based on the production of chemical messengers by the enzymatic subunit, which induces the detachment of the reporter molecules from the silica surface. As a proof of concept, a urea nanosensor based on the release of Alexa-Fluor-647-labeled oligonucleotide from enzyme-functionalized Janus gold-mesoporous-silica nanoparticles (Au-MSNPs) was developed. The Janus particles were functionalized on the silica face with amino groups to which the labeled oligonucleotides were attached by electrostatic interactions, whereas the gold face was used for grafting urease enzymes. The nanodevice was able to release the fluorescent oligonucleotide through the enzyme-mediated hydrolysis of urea to ammonia and the subsequent deprotonation of amino groups on the silica face. This simple nanodevice was applied for the fluorometric detection of urea in real human blood samples and for the identification of adulterated milk. Given the large variety of enzymes and reporter species that could be combined, this is a general new paradigm that could be applied to the design of a number of optical probes for the detection of target analytes., A.L.-L. is grateful to "La Caixa" Banking Foundation for his Ph.D. fellowship. The authors thank to the Spanish Government (MINECO Projects MAT2015-64139-C4-1, AGL2015-70235-C2-2-R, CTQ2014-58989-P and CTQ2015-71936-REDT) and the Generalitat Valencia (Projects PROMETEOII/2014/047, PROMETEO2018/024) for support. The Comunidad de Madrid (S2013/MIT-3029, Programme NANOAVANSENS) is also gratefully acknowledged.
- Published
- 2019
18. Highly Active Hydrogenation Catalysts Based on Pd Nanoparticles Dispersed along Hierarchical Porous Silica Covered with Polydopamine as Interfacial Glue
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Miguel Ródenas, Jamal El Haskouri, Pedro Amorós, Francisco Pérez-Pla, M. Angeles Ubeda, José V. Ros-Lis, and M. Dolores Marcos
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Materials science ,Catalitzadors ,Composite number ,bimodal porosity ,chemistry.chemical_element ,Nanoparticle ,02 engineering and technology ,lcsh:Chemical technology ,010402 general chemistry ,01 natural sciences ,Catalysis ,4-nitrophenol ,lcsh:Chemistry ,chemistry.chemical_compound ,lcsh:TP1-1185 ,mesoporous silica ,Physical and Theoretical Chemistry ,polydopamine ,Substrate (chemistry) ,Selective catalytic reduction ,4-Nitrophenol ,Mesoporous silica ,palladium ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,lcsh:QD1-999 ,chemistry ,Chemical engineering ,catalytic reduction ,nanoparticles ,Materials nanoestructurats ,0210 nano-technology ,Palladium - Abstract
New catalysts based on Pd(0) nanoparticles (Pd NPs) on a bimodal porous silica of the UVM-7/polydopamine (PDA) support have been synthesized following two preparative strategies based on the sequential or joint incorporation of two components of the composite (Pd and PDA). We analyzed the role played by the PDA as &lsquo, interfacial glue&rsquo, between the silica scaffold and the Pd NPs. The catalysts were tested for the hydrogenation of 4-nitrophenol using (NEt4)BH4 as the hydrogenating agent. In addition to the palladium content, the characterization of the catalysts at the micro and nanoscale has highlighted the importance of different parameters, such as the size and dispersion of the Pd NPs, as well as their accessibility to the substrate (greater or lesser depending on their entrapment level in the PDA) on the catalytic efficiency. Staged sequential synthesis has led to better catalytic results. The most active Pd(0) centers seem to be Pd NPs of less than 1 nm on the PDA surface. The efficiency of the catalysts obtained is superior to that of similar materials without PDA. A comprehensive comparison has been made with other catalysts based on Pd NPs in a wide variety of supports. The TOF values achieved are among the best described in the literature.
- Published
- 2020
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19. Functional Magnetic Mesoporous Silica Microparticles Capped with an Azo-Derivative: A Promising Colon Drug Delivery Device
- Author
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Daniel Ferri, Ana M. Costero, M. Dolores Marcos, Ramón Martínez-Máñez, Pablo Gaviña, Carmen Coll, Virginia Merino, Adrián H. Teruel, Marta González-Álvarez, Félix Sancenón, and Margarita Parra
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Pharmaceutical Science ,02 engineering and technology ,Ferric Compounds ,01 natural sciences ,azo reductor ,colon release ,Analytical Chemistry ,Sodium dithionite ,chemistry.chemical_compound ,QUIMICA ORGANICA ,Drug Discovery ,Moiety ,magnetic mesoporous silica ,Drug Carriers ,Aqueous solution ,Hydrolysis ,Hydrogen-Ion Concentration ,Silicon Dioxide ,021001 nanoscience & nanotechnology ,Controlled release ,Microspheres ,Chemistry (miscellaneous) ,Drug delivery ,Molecular Medicine ,0210 nano-technology ,Oxidation-Reduction ,Porosity ,Colon ,Surface Properties ,010402 general chemistry ,Article ,Magnetics ,Chlorides ,Safranin ,QUIMICA ANALITICA ,Humans ,Ferrous Compounds ,Physical and Theoretical Chemistry ,azo derivatives ,pH triggered ,QUIMICA INORGANICA ,Organic Chemistry ,Dithionite ,Mesoporous silica ,0104 chemical sciences ,Drug Liberation ,chemistry ,Nanoparticles ,Phenazines ,Mesoporous material ,Azo Compounds ,Nuclear chemistry - Abstract
[EN] Magnetic micro-sized mesoporous silica particles were used for the preparation of a gated material able to release an entrapped cargo in the presence of an azo-reducing agent and, to some extent, at acidic pH. The magnetic mesoporous microparticles were loaded with safranin O and the external surface was functionalized with an azo derivative 1 (bearing a carbamate linkage) yielding solid S1. Aqueous suspensions of S1 at pH 7.4 showed negligible safranin O release due to the presence of the bulky azo derivative attached onto the external surface of the inorganic scaffold. However, in the presence of sodium dithionite (azoreductive agent), a remarkable safranin O delivery was observed. At acidic pH, a certain safranin O release from S1 was also found. The pH-triggered safranin O delivery was ascribed to the acid-induced hydrolysis of the carbamate moiety that linked the bulky azo derivatives onto the mesoporous inorganic magnetic support. The controlled release behavior of S1 was also tested using a model that simulated the gastro intestinal tract., We thank the Spanish Government (projects MAT2015-64139-C4-1-R and AGL2015-70235C2-2-R (MINECO/FEDER)) and the Generalitat Valenciana (project PROMETEOII/2014/047) for support. AHT thanks to the Spanish MEC for his FPU grant. The authors also thank the Electron Microscopy Service at the Universitat Politecnica de Valencia for support. SCSIE (Universitat de Valencia) is also gratefully acknowledged for all the equipment employed. NMR was registered at the U26 facility of ICTS "NANBIOSIS" at the Universitat de Valencia. The authors thanks L.A. Villaescusa for his helpful discussion about the 1H-NMR analysis of the composition of loaded and functionalized supports.
- Published
- 2018
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20. Anilinopyridine metal complexes for the selective chromogenic sensing of cyanide anion
- Author
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Ramón Martínez-Máñez, Beatriz Lozano-Torres, Knut Rurack, Teresa Pardo, M. Dolores Marcos, and Félix Sancenón
- Subjects
Cyanide ,Inorganic chemistry ,Fe(III) complex ,010402 general chemistry ,01 natural sciences ,Charge-transfer ,Metal ,chemistry.chemical_compound ,Chromogenic ,QUIMICA ORGANICA ,Pyridine ,Bathochromic shift ,Materials Chemistry ,Physical and Theoretical Chemistry ,Acetonitrile ,010405 organic chemistry ,QUIMICA INORGANICA ,Chromophore ,0104 chemical sciences ,Anilinopyridine ,chemistry ,Absorption band ,visual_art ,visual_art.visual_art_medium - Abstract
[EN] Probe 1, which contains an anilinopyridine chromophore and an aza-oxa macrocyclic subunit, presented an absorption band centered at 340 nm in acetonitrile. Addition of Fe(III), Cr(III) and Hg(II) induced the growth of a new absorption band at 430 nm (with color change from colorless to yellow), whereas in the presence of Cu(II), Zn(II) and Pb(II), less marked changes were observed. The color changes observed upon addition of Fe(III), Cr(III) and Hg(II) were ascribed to the formation of 1:1 stoichiometry complexes with probe 1. Coordination of Fe(III), Cr(III) and Hg(II) with the pyridine fragment of 1 induced an enhancement of the charge transfer character accompanied with a marked bathochromic shift that was reflected in a color change from colorless to yellow. The strength of the interaction between probe 1 and Fe(III) cation was modulated upon interaction with anions. Of all the anions tested, only cyanide was able to induce the bleaching of the yellow 1Fe(III) complex solution. This bleaching was ascribed to the formation of 1Fe(III)-CN complex that restored, to some extent, the optical features of the free probe allowing the chromogenic sensing of cyanide. Besides, 1Fe(III) complex was used to detect cyanide in acetonitrile-water 90:10 v/v mixtures with good recoveries., This work was supported by the Generalitat Valenciana [grant number PROMETEOII/2014/047]; Ministerio de Economia y Competitividad [grant number MAT2015-64139-C4-1-R], [grant number AGL2015-70235-C2-2-R (MINECO/FEDER)].
- Published
- 2018
21. epsilon-Polylysine-Capped Mesoporous Silica Nanoparticles as Carrier of the C9h Peptide to Induce Apoptosis in Cancer Cells
- Author
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M. Dolores Marcos, José Ramón Murguía, Leticia Dominguez-Berrocal, Jerónimo Bravo, Cristina de la Torre, Ramón Martínez-Máñez, and Félix Sancenón
- Subjects
Peptide ,Apoptosis ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,Catalysis ,Gated nanoparticles ,HeLa ,chemistry.chemical_compound ,QUIMICA ORGANICA ,Annexin ,QUIMICA ANALITICA ,BIOQUIMICA Y BIOLOGIA MOLECULAR ,Humans ,Polylysine ,Viability assay ,Amino Acid Sequence ,Protein Phosphatase 2 ,chemistry.chemical_classification ,Drug Carriers ,Microscopy, Confocal ,biology ,Chemistry ,Circular Dichroism ,Organic Chemistry ,QUIMICA INORGANICA ,General Chemistry ,Mesoporous silica ,021001 nanoscience & nanotechnology ,biology.organism_classification ,Silicon Dioxide ,Caspase 9 ,0104 chemical sciences ,Drug delivery ,Cancer cell ,Biophysics ,Nanoparticles ,Phenazines ,0210 nano-technology ,Peptides ,Porosity ,Caspase-9 ,HeLa Cells - Abstract
[EN] Apoptotic signaling pathways are altered in numerous pathologies such as cancer. In this scenario, caspase-9/PP2Ac alpha interaction constitutes a key target with pharmacological interest to re-establish apoptosis in tumor cells. Very recently, a short peptide (C9h) known to disrupt caspase-9/PP2Ac alpha interaction with subsequent apoptosis induction was described. Here, we prepared two sets of mesoporous silica nanoparticles loaded with safraninO (S2) or with C9h peptide (S4) and functionalized with epsilon-polylysine as capping unit. Aqueous suspensions of both nanoparticles showed negligible cargo release whereas in the presence of pronase, a marked delivery of safraninO or C9h was observed. Confocal microscopy studies carried out with HeLa cells indicated that both materials were internalized and were able to release their entrapped cargos. Besides, a marked decrease in HeLa cell viability (ca. 50%) was observed when treated with C9h-loaded S4 nanoparticles. Moreover, S4 provides peptide protection from degradation additionally allowing for a dose reduction to observe an apoptotic effect when compared with C9h alone or in combination with a cell-penetrating peptide (i.e., Mut3DPT-C9h). Flow cytometry studies, by means of Annexin V-FITC staining, showed the activation of apoptotic pathways in HeLa as a consequence of S4 internalization, release of C9h peptide and disruption of caspase-9/PP2Ac alpha interaction., The authors wish to express their gratitude to the Spanish government (Projects MAT2015-64139-C4-1, SAF2012-31405, SAF2015-67077-R, AGL2015-70235-C2-2-R (MINECO/FEDER)), the Generalitat Valencia (Projects PROMETEOII/2014/047, PROMETEO/2012/061) and the CIBER-BBN for their support. C.T. is grateful to the Spanish Ministry of Science and Innovation for her Ph.D. fellowship.
- Published
- 2018
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22. 11B-MAS NMR approach to the boron adsorption mechanism on a glucose-functionalised mesoporous silica matrix
- Author
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Félix Sancenón, Pedro Amorós, Ramón Martínez-Máñez, M. Dolores Marcos, Cristina Sanfeliu, Juan Soto, Thierry Azaïs, Universitat Politècnica de València (UPV), Spectroscopie, Modélisation, Interfaces pour L'Environnement et la Santé (SMiLES), Laboratoire de Chimie de la Matière Condensée de Paris (LCMCP), and Université Pierre et Marie Curie - Paris 6 (UPMC)-Collège de France (CdF (institution))-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Collège de France (CdF (institution))-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
Materials science ,Boron adsorption modelling ,Solid-state ,chemistry.chemical_element ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,Isothermal process ,Matrix (chemical analysis) ,Adsorption ,QUIMICA ORGANICA ,General Materials Science ,Boron ,Extraction (chemistry) ,QUIMICA INORGANICA ,General Chemistry ,[CHIM.MATE]Chemical Sciences/Material chemistry ,B-11 MAS NMR ,Mesoporous silica ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Gluconamide-functionalised porous materials ,0104 chemical sciences ,Sugar derivatives ,[CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry ,Chemical engineering ,chemistry ,Mechanics of Materials ,0210 nano-technology - Abstract
[EN] Boron chemistry has raised much interest because, despite the difference between necessities and toxicity being very narrow, it is still widely used in industrial processes. In a previous work we reported an adsorbent for boron extraction from water by the functionalisation of a UVM-7 mesoporous silica matrix with gluconamide moieties. The ability of this material to adsorb boron is based on its well-known affinity for coordinating the cis-diols present in attached saccharide. Although much research on the formation of boron esters with sugars and sugar derivatives in solution has been done, very few reports have dealt with the adsorption mechanism of boron onto functionalised materials in the solid state. Hence an in-depth study of the adsorption process was conducted in this paper. For this purpose, several solids with increasing boron contents were prepared from the gluconamide-functionalised UVM-7 material and an isothermal boron adsorption curve was obtained. The B-11 and C-13 MAS NMR techniques were used to characterise the obtained solids, and the simulation of the boron NMR and isothermal adsorption combined data was accomplished to enlighten the boron adsorption process. A model with three different coordination environments, two possible adsorption sites and the presence of oligomeric boron species allowed us to reproduce not only the isothermal boron adsorption curve, but also the evolution of the integrated areas for the signals in the B-11 MAS NMR spectra obtained for the different boron-containing gluconamide-functionalised UVM-7 materials., Financial support from the Spanish Government (Project MAT2009-14564-C04-01 and MAT2012-38429-C04-01) and the Generalitat Valenciana (Project PROMETEO/2009/016) is gratefully acknowledged. C.S. thanks the MICINN for a predoctoral fellowship.
- Published
- 2018
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23. Ceramic foam supported active materials for boron remediation in water
- Author
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Juan Soto, Cristina Sanfeliu, Félix Sancenón, Pedro Amorós, Ramón Martínez-Máñez, and M. Dolores Marcos
- Subjects
INGENIERIA DE LA CONSTRUCCION ,Materials science ,General Chemical Engineering ,chemistry.chemical_element ,Context (language use) ,QUIMICA ORGANICA ,Adsorption ,General Materials Science ,Ceramic ,Boron ,Water Science and Technology ,Functionalized mesoporous adsorbents ,Ceramic foam ,Aqueous solution ,Mechanical Engineering ,QUIMICA INORGANICA ,Ceramic monoliths supported mesoporous adsorbents ,General Chemistry ,Mesoporous silica ,Ceramic monoliths as supporting matrices ,Boron remediation ,chemistry ,Chemical engineering ,visual_art ,visual_art.visual_art_medium ,Mesoporous material - Abstract
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 macroscopic supports. The efficiency of these new composites for boron removal is very high and comparable with the parent microparticulated adsorbent., Financial support from the Spanish Government (Project MAT2009-14564-C04-01 and MAT2009-14564-C04-04, and MAT2012-38429-C04-01 and MAT2012-38429-C04-02) and the Generalitat Valenciana (Project PROMETEO/2009/016) is gratefully acknowledged. C.S. thanks the MICINN for a predoctoral fellowship.
- Published
- 2015
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- View/download PDF
24. Gated Porous Materials for Biomedical Applications
- Author
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Elena Aznar, Félix Sancenón, M. Dolores Marcos, Erick Yu, and Ramón Martínez-Máñez
- Subjects
Materials science ,Nanotechnology ,Porous medium - Published
- 2017
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- View/download PDF
25. Two New Fluorogenic Aptasensors Based on Capped Mesoporous Silica Nanoparticles to Detect Ochratoxin A
- Author
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Ramón Martínez-Máñez, Àngela Ribes, Sara Santiago-Felipe, Andrea Bernardos, Félix Sancenón, Elena Aznar, M. Dolores Marcos, and Teresa Pardo
- Subjects
INGENIERIA DE LA CONSTRUCCION ,Materials science ,Aptamer ,aptamers ,Nanoparticle ,Nanotechnology ,02 engineering and technology ,mesoporous materials ,010402 general chemistry ,sensors ,01 natural sciences ,Aptamers ,Electron Microscopy Service of the UPV ,Nanomaterials ,QUIMICA ORGANICA ,QUIMICA ANALITICA ,nanostructures ,Detection limit ,Full Paper ,Sensors ,QUIMICA INORGANICA ,Ochratoxin A ,General Chemistry ,Full Papers ,Mesoporous silica ,021001 nanoscience & nanotechnology ,Mesoporous materials ,0104 chemical sciences ,Nanostructures ,Covalent bond ,0210 nano-technology ,Mesoporous material ,Selectivity ,ochratoxin A - Abstract
[EN] Aptamers have been used as recognition elements for several molecules due to their great affinity and selectivity. Additionally, mesoporous nanomaterials have demonstrated great potential in sensing applications. Based on these concepts, we report herein the use of two aptamer¿capped mesoporous silica materials for the selective detection of ochratoxin¿A (OTA). A specific aptamer for OTA was used to block the pores of rhodamine¿B¿loaded mesoporous silica nanoparticles. Two solids were prepared in which the aptamer capped the porous scaffolds by using a covalent or electrostatic approach. Whereas the prepared materials remained capped in water, dye delivery was selectively observed in the presence of OTA. The protocol showed excellent analytical performance in terms of sensitivity (limit of detection: 0.5¿0.05¿nm), reproducibility, and selectivity. Moreover, the aptasensors were tested for OTA detection in commercial foodstuff matrices, which demonstrated their potential applicability in real samples, We thank the Spanish Government (projects MAT2015-64139-C4-1-R and AGL2015-70235-C2-2-R (MINECO/FEDER)) and the Generalitat Valenciana (project PROMETEOII/2014/047) for support. A.R. thanks UPV for her predoctoral fellowship. S.S. thanks the Instituto de Salud Carlos III and the European Social Fund for the financial support "Sara Borrell" (CD16/000237). A.B. thanks the Spanish Government for financial support by the "Juan de la Cierva-Incorporacion" (IJCI-2014-21534). The authors also thank the Electron Microscopy Service at UPV for support.
- Published
- 2017
26. Au-Mesoporous silica nanoparticles gated with disulfide-linked oligo(ethylene glycol) chains for tunable cargo delivery mediated by an integrated enzymatic control unit
- Author
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Alba García-Fernández, M. Dolores Marcos, Antoni Llopis-Lorente, Paula Díez, Reynaldo Villalonga, Félix Sancenón, Alfredo Sánchez, Ramón Martínez-Máñez, and Beatriz de Luis
- Subjects
INGENIERIA DE LA CONSTRUCCION ,Materials science ,Biomedical Engineering ,Nanoparticle ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,chemistry.chemical_compound ,QUIMICA ORGANICA ,Safranin ,QUIMICA ANALITICA ,BIOQUIMICA Y BIOLOGIA MOLECULAR ,Organic chemistry ,General Materials Science ,Nanodevice ,chemistry.chemical_classification ,QUIMICA INORGANICA ,General Chemistry ,General Medicine ,Mesoporous silica ,021001 nanoscience & nanotechnology ,Combinatorial chemistry ,0104 chemical sciences ,Enzyme ,chemistry ,Acetylthiocholine ,Nanocarriers ,0210 nano-technology ,Ethylene glycol - Abstract
[EN] We report a delivery system based on Au-mesoporous silica (MS) nanoparticles functionalized with acetylcholinesterase on the Au face as a control unit and with disulfide-containing oligo(ethylene glycol) chains on the MS face as caps. The control unit handles the chemical information in the environment (the presence of acetyl-thiocholine or enzyme inhibitors) that results in a tuned cargo delivery from the nanocarrier. The nanodevice displayed an enhanced cargo delivery in cancer cells (safranin O and doxorubicin) in the presence of acetylthiocholine., A. Llopis-Lorente thanks "La Caixa" Banking Foundation for his PhD fellowship. A. Garcia-Fernandez is grateful to the Spanish government for an FPU grant. The authors are grateful to the Spanish Government (MINECO Projects MAT2015-64139-C4-1, CTQ2014-58989-P and CTQ2015-71936-REDT) and the Generalitat Valencia (Project PROMETEOII/2014/047) for support. The Comunidad de Madrid (S2013/MIT-3029, Programme NANOAVANSENS) is also gratefully acknowledged.
- Published
- 2017
27. Oligonucleotide-capped mesoporous silica nanoparticles as DNA-responsive dye delivery systems for genomic DNA detection
- Author
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Lluís Pascual, Knut Rurack, Pedro Amorós, Elena Aznar, José Ramón Murguía, Isabel Baroja, Ramón Martínez-Máñez, Félix Sancenón, and M. Dolores Marcos
- Subjects
DNA, Bacterial ,INGENIERIA DE LA CONSTRUCCION ,Design ,Controlled-release ,Supports ,Oligonucleotides ,Nanoparticle ,Nanotechnology ,Catalysis ,Legionella pneumophila ,chemistry.chemical_compound ,QUIMICA ORGANICA ,hemic and lymphatic diseases ,Candida albicans ,BIOQUIMICA Y BIOLOGIA MOLECULAR ,Materials Chemistry ,Mycoplasma fermentans ,Coloring Agents ,Stimuli ,Rhodamines ,Oligonucleotide ,Chemistry ,QUIMICA INORGANICA ,Metals and Alloys ,Genomics ,General Chemistry ,Mesoporous silica ,Silicon Dioxide ,Controlled release ,Drug-delivery ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,genomic DNA ,Drug delivery ,Ceramics and Composites ,Nanoparticles ,DNA - Abstract
[EN] New hybrid oligonucleotide-capped mesoporous silica nanoparticles able to detect genomic DNA were designed., Financial support from the Spanish Government (Project MAT2012-38429-C04) and the Generalitat Valencia (Project PROMETEOII/2014/047) is gratefully acknowledged. Ll. P. is grateful to the Universidad Politecnica de Valencia for his grant.
- Published
- 2015
- Full Text
- View/download PDF
28. Selektiver, hoch empfindlicher und schneller Nachweis genomischer DNA mit gesteuerten Materialien am Beispiel vonMycoplasma
- Author
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Enrique Pérez-Payá, Knut Rurack, Laura Mondragón, José Ramón Murguía, Estela Climent, Pedro Amorós, M. Dolores Marcos, Ramón Martínez-Máñez, and Félix Sancenón
- Subjects
INGENIERIA DE LA CONSTRUCCION ,Mycoplasma ,QUIMICA ORGANICA ,QUIMICA ANALITICA ,QUIMICA INORGANICA ,BIOQUIMICA Y BIOLOGIA MOLECULAR ,Mesoporöse Träger ,Gesteuerte Materialien ,DNA ,General Medicine ,Sonden - Abstract
[DE] Mit DNA verschlossene und mit Farbstoff beladene mesoporöse Siliciumdioxid-Nanopartikel wurden zum Nachweis von Mycoplasma bis zu einer Nachweisgrenze von ca. 70 genomischen DNA-Kopien pro mu-L in real kontaminierten Zellkulturmedien ohne die Hilfe von PCR-Techniken eingesetzt., Diese Arbeit wurde durch die Spanische Regierung (MAT2009-14564-C04-01 und SAF2010 15512) und die Generalitat Valenciana (PROMETEO/2009/016 und 2010/005) unterstützt. E.C. dankt dem Spanischen Bildungsministerium für ein Stipendium
- Published
- 2013
- Full Text
- View/download PDF
29. Selective, Highly Sensitive, and Rapid Detection of Genomic DNA by Using Gated Materials:MycoplasmaDetection
- Author
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Ramón Martínez-Máñez, Laura Mondragón, Félix Sancenón, Enrique Pérez-Payá, Knut Rurack, José Ramón Murguía, Pedro Amorós, Estela Climent, and M. Dolores Marcos
- Subjects
DNA, Bacterial ,INGENIERIA DE LA CONSTRUCCION ,Supports ,Mesoporous silica nanoparticles ,Fermentans ,Responsive controlled release ,Amplification ,mesoporous materials ,Biology ,sensors ,medicine.disease_cause ,Rapid detection ,Catalysis ,gated materials ,chemistry.chemical_compound ,Mycoplasma ,QUIMICA ORGANICA ,Contamination ,QUIMICA ANALITICA ,BIOQUIMICA Y BIOLOGIA MOLECULAR ,medicine ,Gated materials ,Rheumatoid arthritis ,mycoplasma ,Controlled drug delivery ,Sensors ,QUIMICA INORGANICA ,Genomics ,DNA ,General Chemistry ,Cell cultures ,Molecular biology ,Highly sensitive ,genomic DNA ,chemistry - Abstract
The coupling of gated-indicator delivery with highly specific biochemical recognition is an innovative strategy for the detection of DNA sequences, able to compete with classical methods which need PCR amplification, in important areas such as point-of-care diagnostics or detection of specific biological contaminations with pathogens. Such comparatively simple and cheap yet highly selective and sensitive assays hold promise for use in less-developed areas of the world., Financial support from the Spanish Government (MAT2009-14564-C04-01 and SAF2010 15512), the Generalitat Valenciana (PROM-ETEO/2009/016 and 2010/005) is gratefully acknowledged. E. C. thanks the Ministerio de Educacion for a fellowship. L. M. thanks Generalitat Valenciana for her Post-Doc VALI + D contract.
- Published
- 2013
- Full Text
- View/download PDF
30. A Mycoplasma Genomic DNA Probe using Gated Nanoporous Anodic Alumina
- Author
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Lluis F. Marsal, Luis Pla, Félix Sancenón, Elisabet Xifré-Pérez, Àngela Ribes, Elena Aznar, Ramón Martínez-Máñez, and M. Dolores Marcos
- Subjects
INGENIERIA DE LA CONSTRUCCION ,02 engineering and technology ,010402 general chemistry ,medicine.disease_cause ,01 natural sciences ,Electron Microscopy Service of the UPV ,chemistry.chemical_compound ,QUIMICA ORGANICA ,QUIMICA ANALITICA ,Rhodamine B ,medicine ,Gated materials ,Detection limit ,biology ,Mycoplasma detection ,Nanoporous ,QUIMICA INORGANICA ,General Chemistry ,Mycoplasma ,DNA ,021001 nanoscience & nanotechnology ,biology.organism_classification ,Fluorescence ,0104 chemical sciences ,genomic DNA ,chemistry ,Biophysics ,Nanoporous anodic alumina ,0210 nano-technology ,Bacteria - Abstract
[EN] A nanoporous anodic alumina (NAA)-based sensor system for the detection of Mycoplasma was developed through the implementation of "molecular gates" selective to the presence of this bacterium. The capped support showed a negligible cargo release, while presence of Mycoplasma genomic DNA resulted in the release of rhodamine B fluorescent dye. This sensor system presents a limit of detection of 20 genomic DNA copies mu L-1 and was applied to the detection of Mycoplasma bacteria in competitive environments, such as culture cell media., We thank the Spanish Government (projects MAT2015-64139-C41-R, AGL2015-70235-C2-2-R, and TEC2015-71324-R (MINECO/FEDER, UE)), the Generalitat Valenciana (project PROMETEOII/2014/047), the Catalan authority (project AGAUR 2014SGR1344), and ICREA under the 2014 ICREA Academia Award for support. L.P. thanks to PROMETEOII/2014/047 for his contract. We thank the Electron Microscopy Service at the UPV for support.
- Published
- 2016
31. Thrombin-Responsive Gated Silica Mesoporous Nanoparticles As Coagulation Regulators
- Author
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Ramón Martínez-Máñez, Abbaraju Venkataraman, Félix Sancenón, Núria Mas, José Ramón Murguía, M. Dolores Marcos, Elena Aznar, Ravishankar Bhat, and Àngela Ribes
- Subjects
INGENIERIA DE LA CONSTRUCCION ,Whole Blood Coagulation Time ,Silicon dioxide ,Nanoparticle ,Nanotechnology ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,Electron Microscopy Service of the UPV ,chemistry.chemical_compound ,Thrombin ,QUIMICA ORGANICA ,QUIMICA ANALITICA ,Electrochemistry ,medicine ,BIOQUIMICA Y BIOLOGIA MOLECULAR ,Animals ,Coagulation (water treatment) ,General Materials Science ,Pentanoic Acids ,Blood Coagulation ,Spectroscopy ,Anticoagulant drug ,Chemistry ,Acenocoumarol ,QUIMICA INORGANICA ,Anticoagulants ,Surfaces and Interfaces ,Mesoporous silica ,Silicon Dioxide ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,0104 chemical sciences ,Biophysics ,Nanoparticles ,Rabbits ,0210 nano-technology ,Mesoporous material ,medicine.drug - Abstract
[EN] The possibility of achieving sophisticated actions in complex biological environments using gated nanoparticles is an exciting prospect with much potential. We herein describe new gated mesoporous silica nanoparticles (MSN) loaded with an anticoagulant drug and capped with a peptide containing a thrombin-specific cleavage site. When the coagulation cascade was triggered, active thrombin degraded the capping peptidic sequence and induced the-release of anticoagulant drugs to delay the clotting process. The thrombin-dependent response was assessed and a significant increase in coagulation time in plasma from 2.6 min to 5 min was found. This work broadens the application of gated silica nanoparticles and demonstrates their ability to act as controllers in a complex scenario such as hemostasis., Authors thank Spanish Government (Project Nos. MAT2012-38429-C04, AGL2012-39597-C02-02) and Generalitat Valenciana (Project No. PROMETEOII/2014/047) for support. R.B. is thankful to Svagata.eu (Erasmus Mundus Action-II program) for his fellowship. A.R. thanks UPV for her predoctoral fellowship. N.M. thanks Spanish MINECO for her FPI fellowship. The authors also thank the Electron Microscopy Service at the UPV for support.
- Published
- 2016
32. Antibody-Capped Mesoporous Nanoscopic Materials: Design of a Probe for the Selective Chromo-Fluorogenic Detection of Finasteride
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Pedro Amorós, Ángel Maquieira, M. Dolores Marcos, Juan Soto, Ramón Martínez-Máñez, Estela Climent, Félix Sancenón, and Eva M. Brun
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Detection limit ,INGENIERIA DE LA CONSTRUCCION ,Aqueous solution ,Chromatography ,QUIMICA INORGANICA ,Nanotechnology ,General Chemistry ,Mesoporous silica ,Full Papers ,MCM-41 ,finasteride ,Matrix (chemical analysis) ,chemistry.chemical_compound ,QUIMICA ORGANICA ,chemistry ,QUIMICA ANALITICA ,hybrid materials ,Finasteride ,Rhodamine B ,antibodies ,Selectivity ,Mesoporous material ,molecular gates - Abstract
[EN] The synthesis of capped mesoporous silica nanoparticles (MSN) conjugated with an antibody (AB) as a gatekeeper has been carried out in order to obtain a delivery system able to release an entrapped cargo (dye) in the presence of a target molecule (antigen) to which the conjugated antibody binds selectively. In particular, MSN loaded with rhodamine B and functionalized on the external surface with a suitable derivative of N-(t-butyl)- 3-oxo-(5a,17b)-4-aza-androst-1-ene-17-carboxamide (finasteride) have been prepared (S1). The addition of polyclonal antibodies against finasteride induced capping of the pores due to the interaction with the anchored hapten-like finasteride derivative to give a MSN¿hapten¿AB nanoparticle S1-AB. It was found that the addition of capped material S1-AB to water solutions containing finasteride resulted in displacement of the antibody, pore uncapping and entrapped-dye release. The response of the gated material is highly selective, and only finasteride, among other steroids, was able to induce a significant uncapping process. Compared with finasteride, the finasteride metabolite was able to release 17% of the dye, whereas the exogen steroids testosterone, metenolone and 16-b-hydroxystanozolol only induced very little release of rhodamine B (lower than 10%) from aqueous suspensions containing sensing solid S1-AB. A detection limit as low as 20 ppb was found for the fluorimetric detection of finasteride. In order to evaluate a possible application of the material for label-free detection of finasteride, the capped material was isolated and stored to give final sensing solid S1-AB-i. It was found to display a similar behavior towards finasteride as to that shown by freshly prepared S1-AB; even after a period of two months, no significant loss of selectivity or sensitivity was noted. Moreover, to study the application for the detection of finasteride in biological samples, this ¿aged¿ material, S1-AB-i, was tested using commercially available blank urine as matrix. Samples containing 70 and 90% blank urine were spiked with a defined amount of finasteride, and the concentration was determined using capped S1-AB-i. Recovery ranges from 94% to 118% were reached., Financial support from the Spanish Government (project MAT2009-14564-C04-01) and the Generalitat Valenciana (Spain) (projects PROMETEO/2009/016 and PROMETEO/2010/008) is gratefully acknowledged. E. C. thanks the Minesterio de Ciencia e Innovacion (MICINN, Spain) for her fellowship.
- Published
- 2012
33. Finely Tuned Temperature-Controlled Cargo Release Using Paraffin-Capped Mesoporous Silica Nanoparticles
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Enrique Pérez-Payá, Laura Mondragón, Pedro Amorós, José V. Ros-Lis, Elena Aznar, Juan Soto, Ramón Martínez-Máñez, M. Dolores Marcos, and Félix Sancenón
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Models, Molecular ,INGENIERIA DE LA CONSTRUCCION ,Guest molecules ,Paraffins ,Paraffin waxes ,Nanoparticle ,mesoporous materials ,MCM-41 ,Phenazine derivative ,Functionalized ,Cell survival ,QUIMICA ORGANICA ,Chemical structure ,X-Ray Diffraction ,Safranin t ,Silicon dioxide ,Controlled release ,Alkyl chain ,Drug Carriers ,Microscopy, Confocal ,Molecular Structure ,Octadecyltrimethoxysilane ,Surface property ,Temperature ,Silica ,General Medicine ,Chemistry ,Antineoplastic agent ,Paraffin ,HeLa cell ,Porosity ,Human ,Materials science ,Drug carrier ,X ray diffraction ,Surface Properties ,Mesoporous silica nanoparticles ,Nanotechnology ,Antineoplastic Agents ,Mesoporous ,Catalysis ,Drug interactions ,Article ,Microscopy, Electron, Transmission ,Humans ,Drug effect ,Delayed release formulation ,Hydrophobic layers ,QUIMICA INORGANICA ,General Chemistry ,Mesoporous silica ,Molecular gates ,Mesoporous materials ,Mcm 41 ,Confocal microscopy ,Solubility ,Doxorubicin ,Delayed-Action Preparations ,drug delivery ,Drug delivery ,Nanoparticles ,Phenazines ,nanoparticles ,Mesoporous material ,controlled release ,molecular gates ,Transmission electron microscopy ,HeLa Cells - Abstract
[EN] Trapped: Mesoporous silica nanoparticles were loaded with a fluorescent guest and functionalized with octadecyltrimethoxysilane. The alkyl chains interact with paraffins, which build a hydrophobic layer around the particle (see picture). Upon melting of the paraffin, the guest molecule is released, as demonstrated in cells for the guest doxorubicin. The release temperature can be tuned by choosing an appropriate paraffin. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim., Financial support from the Spanish Government (projects MAT2009-14564-C04-01 and SAF2010-15512) and the Generalitat Valenciana (projects PROMETEO/2009/016 and PROMETEO/2010/005) is gratefully acknowledged. L.M. thanks the Generalitat Valenciana for a VALi+d postdoctoral contract. We thank UPV electron microscopy and CIPF confocal microscopy services for technical support.
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- 2011
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34. Fatty Acid Carboxylate- and Anionic Surfactant-Controlled Delivery Systems That Use Mesoporous Silica Supports
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Carmen Coll, Juan Soto, Joan Cano, Elena Aznar, Félix Sancenón, Pedro Amorós, Ramón Martínez-Máñez, Eliseo Ruiz, and M. Dolores Marcos
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Chemistry ,Organic Chemistry ,Inorganic chemistry ,General Chemistry ,Mesoporous silica ,Chloride ,Catalysis ,Bipyridine ,chemistry.chemical_compound ,Thiourea ,Polymer chemistry ,medicine ,Ethanesulfonic acid ,Carboxylate ,Hybrid material ,Mesoporous material ,medicine.drug - Abstract
We report the preparation of a MCM-41 mesoporous material that contains the dye [Ru(bipy) 3 ]Cl 2 (bipy= bipyridine) inside the mesopores and functionalised with suitable binding groups at the entrance of the pores. Solids S1―S3 were obtained by the reaction of the mesoporous material with N-methyl-N'-propyltrimethoxysilylimidazolium chloride, N-phenyl-N'-[3-(trimethoxysilyl)propyl]thiourea, or N-phenyl-N'-[3-(trimethoxysilyl)propy1]urea, respectively. A study of the dye delivery of these systems in buffered water (pH 7.0, 2-[4-(2-hydroxyethyl)piperazin-1-yl]ethanesulfonic acid (HEPES), 10 ―3 mol dm ―3 ) in the presence of a family of carboxylate ions was carried out. In the interaction of the anions with the surface of the solids, the response depends on the characteristics of the binding groups (i.e., imidazolium, urea and thiourea) at the pore outlets and their specific interaction with the corresponding anion. The interaction of long-chain carboxylate ions with the binding sites at the surface of the solids resulted in a remarkable inhibition of the delivery of the dye. This inhibition was observed clearly for the dodecanoate anion, whereas the octanoate, decanoate, cholate, deoxycholate, glycodeoxycholate and taurocholate anions induced a certain pore blockage that varied according to the solid studied. The interaction of smaller anions, such as acetate, butanoate, hexanoate and octanoate, with the solids had no effect on the dye release process. The possible use of the gating system for the chromo-fluorogenic detection of anionic surfactants through selective dye delivery inhibition was also explored. Molecular dynamic simulations that use force-field methods have been made to theoretically study the capping carboxylate mechanism. The calculations are in agreement with the experimental results, thus allowing a representation of the dye delivery inhibition in the presence of long-chain carboxylate ions.
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- 2010
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35. Chromogenic Detection of Nerve Agent Mimics by Mass Transport Control at the Surface of Bifunctionalized Silica Nanoparticles
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Estela Climent, Santiago Royo, Salvador Gil, Ana M. Costero, Félix Sancenón, Margarita Parra, M. Dolores Marcos, Juan Soto, Almudena Martí, and Ramón Martínez-Máñez
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Chromogenic ,Silicon dioxide ,Polyethylene Terephthalates ,Molecularly imprinted polymer ,Nanoparticle ,Nanotechnology ,General Chemistry ,General Medicine ,Chromogenic Compounds ,Silicon Dioxide ,Catalysis ,chemistry.chemical_compound ,chemistry ,Phenols ,Reagent ,Nanoparticles ,Colorimetry ,Naked eye ,Chemical Warfare Agents ,Sulfhydryl Compounds ,Coloring Agents ,Cyclobutanes - Abstract
Chemical warfare (CW) agents are toxic chemicals that have been used in several terrorist attacks in recent years. Among CW species, nerve agents are probably the most dangerous; their high toxicity and facile synthesis underscores the need to detect these lethal compounds with quick, reliable procedures. Analytical methods based on enzymatic assays and physical measurements have generally been used to detect these hazards. However, these protocols usually have limitations such as low selectivity, poor portability, and a certain level of complexity. In recent years, several chromogenic and fluorogenic sensors, and reagents for the detection of nerve agents have been described. For instance, approaches that involve perborate-mediated oxidation of organophosphorus agents, fluorescent probes based on polyethylene terephthalate (PET), assays that use oximate-containing derivatives, molecularly imprinted polymers, nanoparticles, carbon nanotubes, porous silicon, displacement-like procedures, and cyclization reactions in push–pull chromophores have been reported. Most of these protocols rely on changes in fluorescence properties, whereas few examples deal with color modulations. Colorimetric detection is particularly appealing because it uses low-cost, widely available instrumentation and allows assays to be detected with the naked eye. However, the development of selective, sensitive chromogenic probes for the detection of deadly chemical species is still rare. Given our interest in the design of novel hybrid organic– inorganic materials as probes, we focused on the preparation of a new optical test for the detection of nerve agent mimics based on nerve agent control of mass transport to the surface of functionalized silica nanoparticles. The chromogenic approach (Scheme 1) involves the use of silica nanoparticles that are functionalized with two different subunits— thiol groups (SH) and aliphatic alcohols (OH). The role of the
- Published
- 2010
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36. Sensitive and Selective Chromogenic Sensing of Carbon Monoxide by Using Binuclear Rhodium Complexes
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Félix Sancenón, Julio Esteban, José V. Ros-Lis, Juan Soto, María E. Moragues, Ramón Martínez-Máñez, and M. Dolores Marcos
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Carbon Monoxide ,Chemistry ,Chromogenic ,Phosphines ,Inorganic chemistry ,Molecular Conformation ,chemistry.chemical_element ,General Chemistry ,General Medicine ,Crystallography, X-Ray ,Catalysis ,Rhodium ,chemistry.chemical_compound ,Coordination Complexes ,Organic chemistry ,Colorimetry ,Carbon monoxide - Published
- 2010
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37. A new approach for the selective and sensitive colorimetric detection of ionic surfactants in water
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M. Dolores Marcos, Félix Sancenón, Ramón Martínez-Máñez, Carmen Coll, Juan Soto, and José V. Ros-Lis
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chemistry.chemical_classification ,Aqueous solution ,Chemistry ,Inorganic chemistry ,Cationic polymerization ,General Chemistry ,Hydrophobic effect ,chemistry.chemical_compound ,Adsorption ,Sulfonate ,Pulmonary surfactant ,MBAS assay ,Materials Chemistry ,Alkyl - Abstract
A novel two-step protocol for the colorimetric detection of ionic surfactants was developed using simple silica supports functionalised with suitable binding groups. Solid S1 was synthesised by reaction of silica with N-methyl-N′-propyltrimethoxysilylimidazolium chloride to obtain a final solid containing imidazolium coordinating moieties. In the first step, solid S1 in contact with anionic surfactant solutions provides the superficial self-assembly organization of the surfactants on the cationic functionalised surface. This layer would be remarkably hydrophobic with the long alkyl chains most likely pointing toward the bulk solution, which in the second step is able to extract a suitable dye (Methylene Blue) from water. The detection principle depends on the fact that the self-assembly process of the anionic surfactant is selective as a consequence of unique strong hydrophobic interactions between surfactant molecules in the monolayer formed. The final behaviour signalling the presence of anionic surfactants would be depletion of the dye solution and coloration of the solid, both visible to the naked eye. A similar protocol was used for the detection of cationic surfactants. In this case solid S2 was prepared containing sulfonate groups. S2 was obtained by reaction of silica with 3-mercaptopropyltriethoxysilane (MPTS) following the oxidation of the mercapto group to sulfonate by adding H2O2. In this case the interaction of cationic surfactants with the S2 surface results in the self-assembly of the cationic surfactants on the anionic surface. In the second step, the addition of a suitable anionic dye (i.e. Patent Blue) then leads to the signalling of the presence of cationic surfactants. S1 and S2 solids were characterised using standard solid-state techniques. A study of the response of these solids was carried out on different concentrations of anionic, cationic and neutral surfactants and in the presence of compulsory water-present anions and cations. The partial decolouration of the dye solution or the corresponding colouration of the solid was related to the concentration of the surfactants in the aqueous solution. The method comprises a novel organic-solvent-free approach for the colorimetric detection of anionic or cationic surfactants. A model was also developed able to interpret the colorimetric behaviour of the solids based on (i) surfactant adsorption on the charged surface and (ii) further extraction of the corresponding dye.
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- 2010
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38. The Determination of Methylmercury in Real Samples Using Organically Capped Mesoporous Inorganic Materials Capable of Signal Amplification
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Pedro Amorós, Knut Rurack, Estela Climent, Juan Soto, Félix Sancenón, Ramón Martínez-Máñez, and M. Dolores Marcos
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Models, Molecular ,Chemistry ,Inorganic chemistry ,Signal Processing, Computer-Assisted ,Nanotechnology ,General Medicine ,General Chemistry ,Methylmercury Compounds ,Catalysis ,chemistry.chemical_compound ,Inorganic materials ,Mesoporous material ,Methylmercury ,Signal amplification - Published
- 2009
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39. Efficient Removal of Anionic Surfactants Using Mesoporous Functionalised Hybrid Materials
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Félix Sancenón, Juan Soto, Carmen Coll, Rakesh Kumar Mahajan, M. Dolores Marcos, and Ramón Martínez-Máñez
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Inorganic chemistry ,Langmuir adsorption model ,Inorganic Chemistry ,chemistry.chemical_compound ,symbols.namesake ,Adsorption ,chemistry ,Pulmonary surfactant ,Pyridine ,symbols ,Surface modification ,Amine gas treating ,Hybrid material ,Mesoporous material - Abstract
A new hybrid system for surfactant removal from water has been developed using mesoporous material (MCM-41) functionalised with suitable binding groups. Solid S1, S2 and S3 were prepared by reaction of the mesoporous material with N-methyl-N′-(propyltrimethoxysilyl)imidazolium chloride, (3-aminopropyl)trimethoxysilane or 4-[(triethoxysilylpropylthio)methyl]pyridine, respectively. The functionalised materials were characterised following standard solid-state techniques. The final prepared solids consist of a siliceous MCM-41-type mesoporous support with the surface decorated by imidazolium, amine and pyridine binding groups suitable for anion coordination. Equilibrium adsorption studies of linear alkylbenzenesulfonate (LAS) using S1, S2 and S3 in water have been carried out. The obtained adsorption data were correlated with a Langmuir isotherm model that gives an acceptable description of the experimental data. The maximum surfactant uptake/binding site (mol mol–1) and the surfactant adsorption capacity (mmol g–1) for materials S1, S2 and S3 were calculated. S1 shows a positive-charged functionalised surface that is independent of the pH of the solution, whereas S2 and S3 are functionalised with neutral groups that need to be protonated in order to display electrostatic binding interactions with the anionic surfactants. Therefore, whereas the adsorption capacity of S1 is pH-independent, S2 and S3 display larger LAS adsorption at acidic pH. The adsorption ability at a certain pH follows the order S1 >> S3 > S2. A remarkable maximum surfactant adsorption of 1.5 mmol per gram of material was observed for S1 at neutral pH. S2 and S3 behave as poorer adsorbents and show maximum surfactant adsorption of 0.197 and 0.335 mmol per gram of material, respectively, at pH 2.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
- Published
- 2009
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40. A Mesoporous 3D Hybrid Material with Dual Functionality for Hg2+Detection and Adsorption
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José V. Ros-Lis, Pedro Amorós, Knut Rurack, Carmen Coll, Ramón Martínez-Máñez, Núria Garro, Juan Soto, María Comes, Jamal El Haskouri, Félix Sancenón, Rosa Casasús, and M. Dolores Marcos
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Squaraine dye ,Aqueous solution ,Molecular Structure ,Surface Properties ,Chemistry ,Silica gel ,Organic Chemistry ,Inorganic chemistry ,Mercury ,General Chemistry ,Silicon Dioxide ,Catalysis ,chemistry.chemical_compound ,Adsorption ,Specific surface area ,Organosilicon Compounds ,Particle Size ,Mesoporous material ,Hybrid material ,Porosity ,Fluorescent Dyes ,Fumed silica - Abstract
Dual-function hybrid material U1 was designed for simultaneous chromofluorogenic detection and removal of Hg(2+) in an aqueous environment. Mesoporous material UVM-7 (MCM41 type) with homogeneously distributed pores of about 2-3 nm in size, a large specific surface area exceeding 1000 m(2) g(-1), and nanoscale particles was used as an inorganic support. The mesoporous solid is decorated with thiol groups that were treated with squaraine dye III to give a 2,4-bis(4-dialkylaminophenyl)-3-hydroxy-4-alkylsulfanylcyclobut-2-enone (APC) derivative that is covalently anchored to the inorganic silica matrix. The solid was characterised by various techniques including X-ray diffraction, transmission electron microscopy, Raman spectroscopy, and nitrogen adsorption. This hybrid solid is the chemodosimeter for Hg(2+) detection. Hg(2+) reacts with the APC fragment in U1 with release of the squaraine dye into the solution, which turns deep blue and fluoresces strongly. Naked-eye Hg(2+) detection is thus accomplished in an easy-to-use procedure. In contrast, U1 remains silent in the presence of other thiophilic transition metal ions, alkali and alkaline earth metal ions, or anions ubiquitously present in water such as chloride, carbonate, sulfate, and phosphate. Material U1 acts not only as chemodosimeter that signals the presence of Hg(2+) down to parts-per-billion concentrations, but at the same time is also an excellent adsorbent for the removal of mercury cations from aqueous solutions. The amount of adsorbed mercury ranges from 0.7 to 1.7 mmol g(-1), depending on the degree of functionalisation. In addition, hybrid material U1 can be regenerated for both sensing and removal purposes. As far as we know, U1 is the first example of a promising new class of polyfunctional hybrid supports that can be used as both remediation and alarm systems by selective signalling and removal of target species of environmental importance. Model compounds based on silica gel (G1), fumed silica (F1), and micrometre-sized MCM-41 scaffolds (M1) were also prepared and studied for comparative purposes.
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- 2008
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41. Nanosized Mesoporous Silica Coatings on Ceramic Foams: New Hierarchical Rigid Monoliths
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David Vie, Julio Latorre, Carmen Guillem, A. Beltran, M. Dolores Marcos, Ramón Martínez-Máñez, Jamal El Haskouri, Pedro Amorós, Aurelio Beltrán, Lenin Huerta, and María Comes
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Ceramic foam ,Materials science ,Macropore ,General Chemical Engineering ,General Chemistry ,engineering.material ,Mesoporous silica ,Colloid ,Coating ,visual_art ,Materials Chemistry ,engineering ,visual_art.visual_art_medium ,Ceramic ,Composite material ,Porosity ,Mesoporous material - Abstract
Silica-based rigid monoliths exhibiting a trimodal hierarchical pore system have been successfully prepared through coating of a ceramic foam (CF) with sub-micro-/nanometric mesoporous particles (as building blocks). We have selected a bimodal porous silica, denoted as UVM-7 (a nanometric version of the well-known MCM-41 materials), consisting of small aggregates of nanometric surfactant-assisted mesoporous particles. A colloidal suspension of this material in water is used to coat through successive impregnation cycles the CF surface. The small intraparticle mesopore system (with pore diameters around 2−3 nm) is due to the supramolecular templating effect of the surfactant. Textural large-mesopores/macropores (in the 20−70 nm range) have their origin in the interparticle UVM-7 voids. The large macrocellular macropores are due to the CF support. The resulting monoliths present a good and homogeneous coverage level. Moreover, these composites display better mechanic properties than those of related silica ...
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- 2007
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42. Gated mesoporous silica nanoparticles for the controlled delivery of drugs in cancer cells
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José Ramón Murguía, Cristina de la Torre, Mónica Gorbe, Elena Aznar, Cristina Giménez, M. Dolores Marcos, Pedro Amorós, Ramón Martínez-Máñez, and Félix Sancenón
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INGENIERIA DE LA CONSTRUCCION ,Cell Survival ,Intracellular Space ,Nanoparticle ,Nanotechnology ,Antineoplastic Agents ,CONTROLLED-RELEASE ,TRIGGERED RELEASE ,Polyethylene Glycols ,chemistry.chemical_compound ,INORGANIC NANOPARTICLES ,QUIMICA ORGANICA ,SYSTEMS ,PEG ratio ,QUIMICA ANALITICA ,Electrochemistry ,medicine ,POLYMER HYBRID NANOPARTICLES ,GLUTATHIONE ,BIOQUIMICA Y BIOLOGIA MOLECULAR ,Humans ,General Materials Science ,Doxorubicin ,Spectroscopy ,Drug Carriers ,ENHANCED PERMEABILITY ,QUIMICA INORGANICA ,Surfaces and Interfaces ,Glutathione ,IN-VITRO ,Mesoporous silica ,Condensed Matter Physics ,Silicon Dioxide ,Controlled release ,GUEST MOLECULES ,Bioavailability ,Drug Liberation ,chemistry ,Delayed-Action Preparations ,Drug Design ,Nanoparticles ,Phenazines ,SUPPORTS ,Ethylene glycol ,Oxidation-Reduction ,Porosity ,medicine.drug ,HeLa Cells - Abstract
In recent years, mesoporous silica nanoparticles (MSNs) have been used as effective supports for the development of controlled-release nanodevices that are able to act as multifunctional delivery platforms for the encapsulation of therapeutic agents, enhancing their bioavailability and overcoming common issues such as poor water solubility and poor stability of some drugs. In particular, redox-responsive delivery systems have attracted the attention of scientists because of the intracellular reductive environment related to a high concentration of glutathione (GSH). In this context, we describe herein the development of a GSH-responsive delivery system based on poly(ethylene glycol)- (PEG-) capped MSNs that are able to deliver safranin O and doxorubicin in a controlled manner. The results showed that the PEG-capped systems designed in this work can be maintained closed at low GSH concentrations, yet the cargo can be delivered when the concentration of GSH is increased. Moreover, the efficacy of the PEG-capped system in delivering the cytotoxic agent doxorubicin in cells was also demonstrated., The authors thank the Spanish Government (Project MAT2012-38429-C04-01), the Generalitat Valenciana (Project PROMETEOII/2014/047), and the Universitat Politecnica de Valencia (Project SP20120795) for support. C.G. and C.d.l.T also thank the Spanish Ministry of Education for their FPU grants. The authors also thank UPV electron microscopy and CIPF confocal microscopy services for technical support.
- Published
- 2015
43. New Methods for Anion Recognition and Signaling Using Nanoscopic Gatelike Scaffoldings
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M. Dolores Marcos, Elena Aznar, Juan Soto, Félix Sancenón, Ramón Martínez-Máñez, Rosa Casasús, and Pedro Amorós
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Chemistry ,Nanotechnology ,General Chemistry ,General Medicine ,Nanoscopic scale ,Catalysis - Published
- 2006
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44. Anchoring Dyes into Multidimensional Large-Pore Zeolites: A Prospective Use as Chromogenic Sensing Materials
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M.ª Carmen Llinares Millán, María Comes, M. Dolores Marcos, Luis A. Villaescusa, José V. Ros-Lis, Félix Sancenón, Juan Soto, and Ramón Martínez-Máñez
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Chromogenic ,Organic Chemistry ,Supramolecular chemistry ,General Chemistry ,Microporous material ,Electrophilic aromatic substitution ,Molecular sieve ,Catalysis ,chemistry.chemical_compound ,Aniline ,chemistry ,Organic chemistry ,Reactivity (chemistry) ,Hybrid material - Abstract
A versatile procedure for anchoring dyes into the pores of multidimensional zeolites by including organic dye precursors in the synthesis gel has been developed. To prove the concept, an aniline-functionalised zeolite Beta was obtained by reaction of triethylorthosilicate (TEOS), tetraethylammonium hydroxide, and N-methyl,N-(propyl-3-trimethoxysilyl)aniline (MPTMSA) in the presence of HF. Further extraction of the structure-directing agents resulted in a highly crystalline, white, functionalised zeolite Beta containing anchored aniline groups. Similar organic functionalised molecular sieves (OFMS) have been explored as novel catalysts, but, as far as we know, OFMS have never been used as precursors for dye-immobilisation or to design new solid-based host systems for selective molecular sensing processes as is reported here. In a second step the solids containing dyes were prepared by reaction of the hybrid material with the appropriate reactives to obtain tricyanovinylbenzene, triphenylpyrylium, azoic, and squaraine derivatives. All these reactions are straightforward and involve electrophilic aromatic substitution or diazotisation reactions at the electron-rich aniline ring. The final dye-functionalised solid materials were isolated by simple filtration and washing procedures and have been characterised by a number of techniques. In all cases the Beta structure of the solid remains unaltered. Among the large number of areas where dye-containing zeolites might be of importance, we were interested in testing their unconventional use as heterosupramolecular hosts in chromogenic protocols. To check their potential use as chemosensors, microporous solids with anchored triphenylpyrilium and squaraine dyes were selected and used as sensors for the chromogenic discrimination of amines. It was found that the response of both solids to amines was basically governed by the three-dimensional (3D) solid architecture that tuned the intrinsic unselective reactivity of the pyrylium dye. By using new solid-state supramolecular chemistry protocols we believe that these, and similar future dye-zeolite hosts, might be promising new sensor materials allowing the visible discrimination of selected target guests by size and/or polarity within families or closely related molecules.
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- 2006
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45. Ein regeneratives Chemodosimeter für die hoch selektive und empfindliche optische Bestimmung von Hg2+, basierend auf der metallinduzierten Bildung eines Farbstoffes
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Juan Soto, M. Dolores Marcos, Ramón Martínez-Máñez, José V. Ros-Lis, and Knut Rurack
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Chemistry ,General Medicine - Published
- 2005
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46. Host Solids Containing Nanoscale Anion-Binding Pockets and Their Use in Selective Sensing Displacement Assays
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Pedro Amorós, Daniel Beltrán, Gertrudis Rodríguez-López, Ramón Martínez-Máñez, María Comes, M. Dolores Marcos, Félix Sancenón, Luis A. Villaescusa, and Juan Soto
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Anions ,Binding Sites ,Molecular Structure ,Stereochemistry ,Chemistry ,General Medicine ,General Chemistry ,Guanidines ,Catalysis ,Models, Chemical ,Microscopy, Electron, Scanning ,Biophysics ,Nanotechnology ,Colorimetry ,Displacement (orthopedic surgery) ,Anion binding ,Porosity ,Nanoscopic scale - Published
- 2005
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47. Rational Design of a Chromo- and Fluorogenic Hybrid Chemosensor Material for the Detection of Long-Chain Carboxylates
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Knut Rurack, Ramón Martínez-Máñez, Hardy Weisshoff, Juan Soto, Pedro Amorós, M. Dolores Marcos, Ana B. Descalzo, and Katrin Hoffmann
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Anions ,Models, Molecular ,Optics and Photonics ,Analyte ,Chemistry ,Molecular sensor ,Analytical chemistry ,Rational design ,Water ,General Chemistry ,Fatty Acids, Nonesterified ,Biochemistry ,Combinatorial chemistry ,Catalysis ,Fluorescence spectroscopy ,Spectrometry, Fluorescence ,Colloid and Surface Chemistry ,Molecular recognition ,Saturated fatty acid ,Moiety ,Coloring Agents ,Mesoporous material ,Nuclear Magnetic Resonance, Biomolecular ,Fluorescent Dyes - Abstract
A strategy for the rational design of a new optical sensor material for the selective recognition of long-chain carboxylates in water is presented. The approach relies on the combination of structure-property relationships to single out the optimal molecular sensor unit and the tuning of the sensing characteristics of an inorganic support material. A spacer-substituted 7-urea-phenoxazin-3-one was employed as the signaling moiety and a mesoporous trimethylsilylated UVM-7 (MCM-41 type) material served as the solid support. The sensor material shows the advantageous features of both modules that is absorption and emission in the visible spectral range, a fluorescence red-shift and enhancement upon analyte coordination, and the amplification of noncovalent (binding) and hydrogen-bonding (recognition) interactions in the detection event. Besides these basic results that are related to the design and performance of the sensor material, the paper discusses general aspects of amido-substituted phenoxazinone photophysics and addresses some general features of molecular anion recognition chemistry in aqueous vs nonaqueous media, utilizing steady-state and time-resolved optical as well as NMR spectroscopies. Detailed studies on potentially competing biochemical species and a first access to the schematic model of the response of the sensor material as obtained by a combination of fluorescence lifetime distribution analysis and Langmuir-type fitting of the gross binding constants complement the key issues of the paper.
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- 2004
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48. High Cobalt Content Mesoporous Silicas
- Author
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M. Dolores Marcos, Julio Latorre, Carmen Guillem, Aurelio Beltrán, Carlos J. Gomez-Garcia, Pedro Amorós, Saúl Cabrera, Jamal El Haskouri, and Daniel Beltrán
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Materials science ,Aqueous solution ,General Chemical Engineering ,Cationic polymerization ,chemistry.chemical_element ,General Chemistry ,chemistry.chemical_compound ,Mesoporous organosilica ,Atrane ,chemistry ,Chemical engineering ,Bromide ,Materials Chemistry ,Organic chemistry ,Dispersion (chemistry) ,Mesoporous material ,Cobalt - Abstract
Silica-based MCM-41-like mesoporous materials with high cobalt content (∞ ≥ Si/Co ≥ 23) have been synthesized through a one-pot surfactant-assisted procedure from aqueous solution using a cationic surfactant (CTMABr = cetyltrimethylammonium bromide) as structural directing agent, and starting from molecular atrane complexes of Co and Si as inorganic hydrolytic precursors. This preparative technique allows optimizing the dispersion of the Co guest species in the silica walls. The mesoporous nature of the final materials is confirmed by XRD, TEM, and N2 adsorption−desorption isotherms. They display unimodal and relatively narrow pore size distributions, whereas their pore array evolves from ordered hexagonal (H0) to wormhole-like (W) as the Co content increases. A careful spectroscopic (UV−visible and NMR) and magnetic study of these materials shows that, regardless of the Si/Co ratio, Co atoms are organized in well-dispersed, uniform CoO nanodomains (ca. 3 nm) partially embedded within the silica walls. Th...
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- 2004
- Full Text
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49. One‐Pot Synthesis of Superparamagnetic CoO‐MCM‐41 Nanocomposites with Uniform and Highly Dispersed Magnetic Nanoclusters
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Julio Latorre, M. Dolores Marcos, Carlos J. Gómez-García, Pedro Amorós, Saúl Cabrera, Jamal El Haskouri, Carmen Guillem, Daniel Beltrán, and Aurelio Beltrán
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Nanocomposite ,Nanoparticle ,chemistry.chemical_element ,Nanoclusters ,Inorganic Chemistry ,MCM-41 ,Chemical engineering ,chemistry ,Triethanolamine ,Polymer chemistry ,medicine ,Mesoporous material ,Cobalt ,Superparamagnetism ,medicine.drug - Abstract
Superparamagnetic CoO-MCM-41 mesoporous nanocomposites, with variable cobalt amounts, in the form of well-dispersed CoO-like clusters, were prepared in a large compositional range by a one-step reproducible procedure employing co-hydrolysis and co-condensation of the inorganic precursors in a water/triethanolamine medium. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
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- 2004
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50. Atrane Precursors in the One-Pot Surfactant-Assisted Synthesis of High Zirconium Content Porous Silicas
- Author
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Pedro Amorós, Julio Latorre, Carmen Guillem, Daniel Beltrán, Saúl Cabrera, M. Dolores Marcos, Jamal El Haskouri, and Aurelio Beltrán
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Zirconium ,Materials science ,Aqueous solution ,General Chemical Engineering ,Inorganic chemistry ,Cationic polymerization ,chemistry.chemical_element ,General Chemistry ,chemistry.chemical_compound ,Atrane ,chemistry ,Transition metal ,Bromide ,Phase (matter) ,Materials Chemistry ,Reactivity (chemistry) - Abstract
A diversity of zirconium-containing porous silicas of the MCM-41 type (Zr−MCM-41, ∞ ≥ Si/Zr ≥ 0.33) has been synthesized from aqueous solution using a cationic surfactant (CTABr = cetyltrimethylammonium bromide) as the structural directing agent, and starting from molecular atrane complexes of Zr and Si as precursors. Atrane inertness toward hydrolysis allows harmonization of the reactivity of the Zr and Si species, which in turn avoids subsequent phase segregation and results in chemically very homogeneous materials. Materials characterization by XRD, TEM, and N2 adsorption−desorption isotherms shows that all the prepared Zr−MCM-41 solids have high surface area and unimodal narrow pore size distribution, whereas their pore packing motives range from ordered hexagonal to wormhole-like arrays depending on the Zr content. The study of the local environment of the Zr atoms in these solids has been approached by means of spectroscopic techniques (IR, UV−vis, and NMR).
- Published
- 2002
- Full Text
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Catalog
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