7 results on '"Andy Hernández-Montoto"'
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2. Finite Element Models of Gold Nanoparticles and Their Suspensions for Photothermal Effect Calculation
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José Manuel Terrés-Haro, Javier Monreal-Trigo, Andy Hernández-Montoto, Francisco Javier Ibáñez-Civera, Rafael Masot-Peris, and Ramón Martínez-Máñez
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Finite Element Methods ,Bioengineering ,photothermal effect ,metal nanoparticles ,plasmonics - Abstract
(1) Background: The ability of metal nanoparticles to carry other molecules and their electromagnetic interactions can be used for localized drug release or to heat malignant tissue, as in the case of photothermal treatments. Plasmonics can be used to calculate their absorption and electric field enhancement, which can be further used to predict the outcome of photothermal experiments. In this study, we model the nanoparticle geometry in a Finite Element Model calculus environment to calculate the effects that occur as a response to placing it in an optical, electromagnetic field, and also a model of the experimental procedure to measure the temperature rise while irradiating a suspension of nanoparticles. (2) Methods: Finite Element Method numerical models using the COMSOL interface for geometry and mesh generation and iterative solving discretized Maxwell’s equations; (3) Results: Absorption and scattering cross-section spectrums were obtained for NanoRods and NanoStars, also varying their geometry as a parameter, along with electric field enhancement in their surroundings; temperature curves were calculated and measured as an outcome of the irradiation of different concentration suspensions; (4) Conclusions: The results obtained are comparable with the bibliography and experimental measurements.
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- 2023
3. 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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4. Gold Nanostars Coated with Mesoporous Silica Are Effective and Nontoxic Photothermal Agents Capable of Gate Keeping and Laser-Induced Drug Release
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José Manuel Terrés, Roberto Montes, Lene B. Oddershede, Javier Ibáñez, Rafael Masot, Mar Orzáez, Elena Aznar, Félix Sancenón, Roberto Cao-Milán, María Dolores Marcos, Ramón Martínez-Máñez, Akbar Samadi, Mónica Gorbe, and Andy Hernández Montoto
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Mesoporous silica shell ,Materials science ,Cell Survival ,Octadecyltrimethoxysilane ,Nanoparticle ,Nanotechnology ,Drug photorelease ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,law.invention ,TECNOLOGIA ELECTRONICA ,chemistry.chemical_compound ,Drug Delivery Systems ,QUIMICA ORGANICA ,law ,CIENCIA DE LOS MATERIALES E INGENIERIA METALURGICA ,QUIMICA ANALITICA ,Humans ,General Materials Science ,Plasmon ,Gold nanostars ,Optical heating ,QUIMICA INORGANICA ,Photothermal therapy ,Mesoporous silica ,Silicon Dioxide ,021001 nanoscience & nanotechnology ,Laser ,Nanostructures ,0104 chemical sciences ,Drug Liberation ,chemistry ,Doxorubicin ,Gold ,Thermosensitive molecular gates ,Nanocarriers ,0210 nano-technology ,Mesoporous material ,Porosity ,HeLa Cells - Abstract
[EN] Herein, a novel drug photorelease system based on gold nanostars (AuNSts), coated with a mesoporous silica shell and capped with paraffin as thermosensitive molecular gate, is reported. Direct measurements of the surface temperature of a single gold nanostar irradiated using a tightly focused laser beam are performed via a heat sensitive biological matrix. The surface temperature of a AuNSt increases by hundreds of degrees (degrees C) even at low laser powers. AuNSts coated with a mesoporous silica shell using a surfactant-templated synthesis are used as chemotherapeutic nanocarriers. Synthetic parameters are optimized to d avoid AuNSt reshaping, and thus to obtain nanoparticles with suitable and stable plasmonic properties for near-infrared (NIR) laser-triggered cargo delivery. The mesoporous silica-coated nanostars are loaded with doxorubicin (Dox) and coated with octadecyltrimethoxysilane and the paraffin heneicosane. The paraffin molecules formed a hydrophobic layer that blocks the pores, impeding the release of the cargo. This hybrid nanosystem exhibits a well-defined photodelivery profile using NIR radiation, even at low power density, whereas the nonirradiated sample shows a negligible payload release. Dox-loaded nanoparticles displayed no cytotoxicity toward HeLa cells, until they are irradiated with 808 nm laser, provoking paraffin melting and drug release. Hence, these novel, functional, and biocompatible nanoparticles display adequate plasmonic properties for NIR-triggered drug photorelease applications., The authors gratefully acknowledge financial support from the Spanish Government (Projects AGL2015-70235-C2-2-R and MAT2015-64139-C4-1-R), the Generalitat Valenciana (Project PROMETEOII/2014/047), and European Union (Programme European Union Action 2 Erasmus Mundus Partnerships, Grant-2014-0870/001-001). A. Samadi and L. B. Oddershede acknowledge financial support from the Novo Nordisk Foundation (NNF14OC0011361) and from the Danish National Research Foundation (DNRF116). A. H. Montoto thanks Erasmus Mundus Programme for his PhD scholarship at EurolnkaNet project. The authors thank UPV electron microscopy and CIPF confocal and electron microscopy services for technical support.
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- 2018
5. A NIR light-triggered drug delivery system using core-shell gold nanostars-mesoporous silica nanoparticles based on multiphoton absorption photo-dissociation of 2-nitrobenzyl PEG
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Mar Orzáez, Borja Díaz de Greñu, José Manuel Terrés, María Dolores Marcos, Roberto Cao-Milán, Roberto Montes, Ramón Martínez-Máñez, María Alfonso, Mónica Gorbe, Andy Hernández-Montoto, Félix Sancenón, and Antoni Llopis-Lorente
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Materials science ,Infrared ,Infrared Rays ,Nanoparticle ,Metal Nanoparticles ,Antineoplastic Agents ,010402 general chemistry ,Photochemistry ,01 natural sciences ,Catalysis ,Dissociation (chemistry) ,Polyethylene Glycols ,TECNOLOGIA ELECTRONICA ,chemistry.chemical_compound ,QUIMICA ORGANICA ,PEG ratio ,QUIMICA ANALITICA ,Materials Chemistry ,Humans ,Irradiation ,neoplasms ,Nitrobenzenes ,Drug Carriers ,010405 organic chemistry ,QUIMICA INORGANICA ,technology, industry, and agriculture ,Metals and Alloys ,General Chemistry ,Mesoporous silica ,equipment and supplies ,Silicon Dioxide ,0104 chemical sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Drug Liberation ,Chemistry ,chemistry ,Doxorubicin ,Drug delivery ,Ceramics and Composites ,Gold ,Ethylene glycol ,Porosity ,HeLa Cells - Abstract
[EN] Gold nanostars coated with a mesoporous silica shell and functionalized with poly(ethylene glycol) containing photolabile 2-nitrobenzyl moieties are able to release doxorubicin after NIR light irradiation at low power irradiance via a multiphoton absorption photo-dissociation process., The authors gratefully acknowledge financial support from the Spanish Government (projects RTI2018-100910-B-C41 and RTI2018-101599-B-C22 (MCUI/AEI/FEDER,UE)), the Generalitat Valenciana (Project PROMETEO2018/024) and the European Union (Programme European Union Action 2-Erasmus Mundus Partnerships, Grant Agreement Number-2014-0870/001-001). A.H.-M. thanks the Erasmus Mundus Programme for his PhD scholarship for the EuroInkaNet project.
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- 2019
6. Janus Gold Nanostars-Mesoporous Silica Nanoparticles for NIR-Light-Triggered Drug Delivery
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María Dolores Marcos, Javier Ibáñez, José Manuel Terrés, Roberto Cao-Milán, Reynaldo Villalonga, Antoni Llopis-Lorente, María Alfonso, Mar Orzáez, Ramón Martínez-Máñez, Borja Díaz de Greñu, Andy Hernández Montoto, Félix Sancenón, and Mónica Gorbe
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Cell Survival ,Infrared Rays ,NIR light ,Supramolecular chemistry ,Nanoparticle ,010402 general chemistry ,Photochemistry ,01 natural sciences ,Catalysis ,HeLa ,TECNOLOGIA ELECTRONICA ,chemistry.chemical_compound ,QUIMICA ORGANICA ,QUIMICA ANALITICA ,Humans ,Molecule ,Irradiation ,Light-responsive nanodevices ,Drug Carriers ,Microscopy, Confocal ,biology ,010405 organic chemistry ,Chemistry ,Organic Chemistry ,QUIMICA INORGANICA ,technology, industry, and agriculture ,Hyperthermia, Induced ,General Chemistry ,Mesoporous silica ,Silicon Dioxide ,biology.organism_classification ,Nanostructures ,0104 chemical sciences ,Doxorubicin ,Succinic acid ,Drug delivery ,Gold ,Porosity - Abstract
[EN] Janus gold nanostar-mesoporous silica nanoparticle (AuNSt-MSNP) nanodevices able to release an entrapped payload upon irradiation with near infrared (NIR) light were prepared and characterized. The AuNSt surface was functionalized with a thiolated photolabile molecule (5), whereas the mesoporous silica face was loaded with a model drug (doxorubicin) and capped with proton-responsive benzimidazole-beta-cyclodextrin supramolecular gatekeepers (N 1). Upon irradiation with NIR-light, the photolabile compound 5 photodissociated, resulting in the formation of succinic acid, which induced the opening of the gatekeeper and cargo delivery. In the overall mechanism, the gold surface acts as a photochemical transducer capable of transforming the NIR-light input into a chemical messenger (succinic acid) that opens the supramolecular nanovalve. The prepared hybrid nanoparticles were non-cytotoxic to HeLa cells, until they were irradiated with a NIR laser, which led to intracellular doxorubicin release and hyperthermia. This induced a remarkable reduction in HeLa cells viability., The authors gratefully acknowledge financial support from the Spanish Government [Projects MAT2015-64139-C4-1-R, AGL2015-70235-C2-2-R and SAF2017-84689-R (MINECO/AEI/FEDER, UE)], the Generalitat Valenciana (Project PROMETEO2018/024) and European Union (Erasmus Mundus Programme, Action 2, grant agreement number 2014-0870/001001). A.H. thanks the Erasmus Mundus Programme for his PhD scholarship through the EuroInkaNet project. A.L.-L. thanks "La Caixa" Banking Foundation for his PhD scholarship.
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- 2019
7. Desarrollo de nanodispositivos basados en nanoestrellas de oro y nanopartículas mesoporosas de sílice para la fotoliberación de fármacos empleando radiaciones del infrarrojo cercano con potenciales aplicaciones en la terapia del cáncer
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Andy Hernández Montoto
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Nanopartículas mesoporosas de sílice ,Radiaciones NIR ,QUIMICA INORGANICA ,Sistemas de fotoliberación de fármacos ,Nanoestrellas de oro ,Terapia del cáncer - Abstract
En este trabajo se han desarrollado cinco sistemas de fotoliberación de doxorrubicina basados en tres tipos de nanopartículas: nanoestrellas de oro recubiertas de una capa mesoporosa de sílice (AuNSt@mSiO2), nanoestrellas de oro (AuNSt) y nanopartículas Janus formadas por nanoestrellas de oro y nanopartículas mesoporosas de sílice (AuNSt-MSNP). Los sistemas sintetizados se basan en dos mecanismos de activación de la liberación, asociados con las propiedades ópticas de las AuNSts. El primer mecanismo está relacionado con la conversión de la energía luminosa en calor, debido a la absorción de la radiación electromagnética por las partículas de oro. El calor generado durante la irradiación de las nanopartículas con un láser del infrarrojo cercano (NIR) se usa, en este caso como estímulo para activar la liberación del fármaco asociado a las nanopartículas. El otro mecanismo está relacionado con la amplificación del campo electromagnético de la radiación en la superficie de las nanopartículas. La amplificación del campo electromagnético favorece la absorción multifotónica de las radiaciones NIR en moléculas que absorben un fotón de mayor energía. Utilizando este mecanismo, se puede activar la fotoliberación del fármaco mediante el empleo de ligandos fotolábiles, que pueden enlazar directamente el fármaco a la partícula permitiendo su liberación después de la fotodescomposición. El primer sistema desarrollado está constituido por AuNSt@mSiO2 funcionalizadas con moléculas de parafina que actúan como puertas moleculares termosensibles. Estas moléculas de parafina en la superficie externa de los poros evitan la liberación de la doxorrubicina. La irradiación del sistema produce la fusión de la parafina debido al calor generado, provocando la liberación al medio del fármaco. Los otros sistemas desarrollados están basados en dos profármacos de la doxorrubicina que se activan al irradiarlas en presencia de las AuNSts generando el fármaco correspondiente. La doxorrubicina se modifica a través de un enlace carbamato con dos ligandos fotolábiles que poseen un espaciador 2-nitrobencílico. Uno de estos ligandos tiene un grupo disulfuro que permite unir el profármaco a la superficie de las AuNSts. La activación se produce debido a la absorción multifotónica de la radiación NIR por los profármacos que se favorece en presencia de las AuNSts, provocando la ruptura del ligando fotolábil y la generación de la doxorrubicina. También se obtuvo un sistema formado por nanopartículas Janus AuNSt-MSNP. El fármaco se encapsula en la MSNP que se funcionaliza con un complejo supramolecular entre el benzimidazol, unido covalentemente a la superficie externa de los poros, y la β-ciclodextrina. Este complejo actúa como puerta molecular sensible al pH evitando la difusión de la doxorrubicina. La superficie de la AuNSt se funcionaliza con un ligando fotolabil tiolado que posee un espaciador 2-nitrobencílico y que tiene enlazado el ácido succínico. La irradiación del sistema híbrido produce la descomposición del ligando en la superficie de la AuNSt y la generación de ácido succínico que provoca la disociación del complejo supramolecular en la superficie de la MSNP, conduciendo finalmente a la liberación del fármaco. Por último, se obtuvo un sistema basado en AuNSt@mSiO2 funcionalizadas con moléculas de polietilenglicol a través de un ligando fotolábil que tiene un espaciador 2-nitrobencílico. El polietilenglicol modificado con el ligando fotolábil actúa como puerta molecular fotosensible impidiendo la difusión del fármaco encapsulado. Al irradiar las partículas se produce la descomposición del ligando, la liberación del PEG y la difusión del fármaco., En aquest treball s'han desenvolupat cinc sistemes de foto-alliberació de doxorrubicina basats en tres tipus de nano-partícules: nano-estreles d'or recobertes d'una capa mesoporosa de sílice (AuNSt@mSiO2), nano-estreles d'or (AuNSt) i nano-partícules Janus formades per nano-estreles d'or i nano-partícules mesoporoses de sílice (AuNSt-MSNP). Els sistemes sintetitzats es basen en dos mecanismes d'activació de l'alliberament associats amb les propietats òptiques de les AuNSts. El primer mecanisme està relacionat amb la conversió de l'energia lluminosa en calor degut a l'absorció de la radiació electromagnètica per les partícules d'or. La calor generat durant la irradiació de les nano-partícules amb un làser de l'infraroig pròxim (NIR) pot utilitzar-se com a estímul per a activar l'alliberament del fàrmac associat a les nano-partícules. L'altre mecanisme està relacionat amb l'amplificació del camp electromagnètic de la radiació en la superfície de les nano-partícules. L'amplificació del camp electromagnètic afavoreix l'absorció multifotònica de les radiacions NIR en molècules que absorbeixen un fotó de major energia. Utilitzant aquest mecanisme es pot activar la foto-alliberació del fàrmac per mitjà de l'ús de lligants foto-làbils que poden enllaçar directament el fàrmac a la partícula permetent el seu alliberament després de la foto-descomposició. El primer sistema desenvolupat està constituït per AuNSt@mSiO2 funcionalitzada amb molècules de parafines que actuen com a portes moleculars termosensibles. Aquestes molècules unides a la superfície externa dels porus eviten la difusió de la doxorrubicina. La irradiació del sistema produeix la fusió de la parafina a causa de la calor generada, provocant l'alliberament al medi del fàrmac. Els altres sistemes desenvolupats estan basats en dos prodrogues de doxorrubicina que s'activen a l'irradiar-les en presència de les AuNSts generant la droga corresponent. La doxorrubicina es modifica a través d'un enllaç carbamat amb dos lligants foto-làbils que posseeixen un espaiador 2-nitrobencílic. Un dels lligants té un grup disulfur que permet unir la prodroga a la superfície de les AuNSts. L'activació es produeix a causa de l'absorció multifotònica de la radiació NIR per les prodrogues que s'afavorix en presència de les AuNSts, provocant la ruptura del lligant foto-làbil i la generació de la doxorrubicina. També es va obtindre un sistema format per nano-partícules Janus AuNSt-MSNP. El fàrmac s'encapsula en la nanopartícula mesoporosa de sílice que es funcionalitza amb un complex supramolecular entre el benzimidazol, unit covalentment a la superfície externa dels porus, i la β-ciclodextrina. Este complex actua com a porta molecular sensible al pH evitant la difusió de la doxorrubicina. La superfície de la AuNSt es funcionaliza amb un lligant foto-làbil tiolat que posseeix un espaiador 2-nitrobencílic i que té enllaçat l'àcid succínic. La irradiació del sistema híbrid produeix la descomposició del lligant en la superfície de l'AuNSt i la generació d'àcid succínic que provoca la dissociació del complex supramolecular en la superfície de la MSNP conduint finalment a l'alliberament de la droga encapsulada. Finalment, es va obtindre un sistema basat en AuNSt@mSiO2 funcionalitzada amb molècules de polietilenglicol a través d'un lligant foto-làbil que té un espaiador 2-nitrobencílic. El polietilenglicol modificat amb el lligant fotolábil actua com a porta molecular fotosensible impedint la difusió de la droga encapsulada. A l'irradiar les partícules es produeix la descomposició del lligant, l'alliberament del PEG i la difusió del fàrmac des de l'interior dels porus., Herein, five doxorubicin photo-release systems based on three types of nanoparticles: gold nanostars coated with a mesoporous silica shell (AuNSt@mSiO2), gold nanostars (AuNSts) and Janus gold nanostars-mesoporous silica nanoparticles (AuNSt-MSNP) have been developed. Photo-release mechanisms are directly related to optical properties of AuNSts. One of them is concerned to the light-heat energy conversion efficiency of AuNSts due to localized surface plasmon resonance associated with the strong absorption of electromagnetic radiation at near infrared wavelengths by anisotropic nanoparticles. Heat evolved during the irradiation of nanoparticles with NIR laser is used as stimulus for triggering drug delivery from the nanoparticles. Another mechanism is related to the strong electromagnetic field enhancement taking place onto nanoparticle¿s surface, which could favour multiphoton absorption of NIR radiations by photolabile molecules. Drug photo-release can be triggered by using photolabile linker which attaches drug to nanoparticle surface due to multiphoton molecular dissociation of linker induced by NIR irradiation. The first developed system is formed by AuNSts coated with mesoporous silica shell capped with paraffins, which act as thermo-sensitive molecular gates. These paraffin molecules onto the external silica surface form a hydrophobic layer that blocks the pores and avoids drug release. NIR irradiation of the hybrid nanoparticles produces plasmonic heating of nanoparticle¿s surrounding and subsequent paraffin melting and drug delivery. Other developed systems are based on two doxorubicin prodrugs, which can be activated by NIR laser irradiation in presence of AuNSts. Doxorubicin was coupled with two photolabile molecules bearing a 2-nitrobenzyl linker via carbamate linkage. One of them has a disulphide group, allowing directly attachment of the prodrug to the nanoparticle¿s surface. Multiphoton absorption of NIR radiation by the doxorubicin prodrug is favoured in presence of AuNSts provoking molecular photodissociation of the 2-nitrobenzyl linker and drug release. A system based on Janus AuNSt-MSNP was also synthesized. Doxorubicin was loaded into MSNPs functionalized onto external surface with a supramolecular complex between benzimidazole (Bzi) and β-cyclodextrin (CD), which acts as pH sensitive molecular gate. AuNSts were modified with thiolated photolabile molecules bearing a 2-nitrobenzyl linker, which anchor succinic acid to nanoparticle¿s surface. NIR irradiation of the hybrid nanoparticles produce photocleavage of 2-nitrobenzyl linker and succinic acid release resulting in dissociation of the Bzi-CD complex and doxorubicin delivery from MSNPs. Finally, a system based on AuNSts coated with mesoporous silica shell capped with polyethyleneglycol (PEG) molecules bearing a 2-nitrobenzyl linker, was developed. These modified PEG molecules act as photosensitive molecular gates, preventing drug release from the mesoporous silica shell. NIR irradiation of these nanoparticles produces the photodissociation of 2-nitrobenzyl linker, leading to PEG release and doxorubicin delivery from the mesoporous silica.
- Published
- 2019
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