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This study aimed to investigate the effect of arabinoxylans (AX) partial de-esterification with feruloyl esterase on the polysaccharide conformational behavior, topographical features, and antioxidant activity. After enzyme treatment, the ferulic acid (FA) content in AX was reduced from 7.30 to 5.48 µg FA/mg polysaccharide, and the molecule registered a small reduction in radius of gyration (RG), hydrodynamic radius (Rh), characteristic ratio (C∞), and persistence length (q). A slight decrease in α and a small increase in K constants in the Mark–Houwink–Sakurada equation for partially de-esterified AX (FAX) suggested a reduction in molecule structural rigidity and a more expanded coil conformation, respectively, in relation to AX. Fourier transform infrared spectroscopy spectra of AX and FAX presented a pattern characteristic for this polysaccharide. Atomic force microscopy topographic analysis of FAX showed a more regular surface without larger hollows in relation to AX. The antioxidant activity of FAX, compared to AX, was reduced by 30 and 41% using both 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS+) and 1,1-diphenyl-2-picryl-hydrazyl (DPPH) methods, respectively. These results suggest that feruloyl esterase treatment of AX could offer a strategy to tailor AX chains conformation, morphological features, and antioxidant activity, impacting the development of advanced biomaterials for biomedical and pharmaceutical applications.
Yubia De Anda-Flores; Elizabeth Carvajal-Millan; Jaime Lizardi-Mendoza; Agustin Rascon-Chu; Judith Tanori-Cordova; Ana Luisa Martínez-López; Alexel J. Burgara-Estrella; Martin R. Pedroza-Montero. Conformational Behavior, Topographical Features, and Antioxidant Activity of Partly De-Esterified Arabinoxylans. Polymers 2021, 13, 2794 .
AMA StyleYubia De Anda-Flores, Elizabeth Carvajal-Millan, Jaime Lizardi-Mendoza, Agustin Rascon-Chu, Judith Tanori-Cordova, Ana Luisa Martínez-López, Alexel J. Burgara-Estrella, Martin R. Pedroza-Montero. Conformational Behavior, Topographical Features, and Antioxidant Activity of Partly De-Esterified Arabinoxylans. Polymers. 2021; 13 (16):2794.
Chicago/Turabian StyleYubia De Anda-Flores; Elizabeth Carvajal-Millan; Jaime Lizardi-Mendoza; Agustin Rascon-Chu; Judith Tanori-Cordova; Ana Luisa Martínez-López; Alexel J. Burgara-Estrella; Martin R. Pedroza-Montero. 2021. "Conformational Behavior, Topographical Features, and Antioxidant Activity of Partly De-Esterified Arabinoxylans." Polymers 13, no. 16: 2794.
Polysaccharide biomaterials have gained significant importance in the manufacture of nanoparticles used in colon-targeted drug delivery systems. These systems are a form of non-invasive oral therapy used in the treatment of various diseases. To achieve successful colonic delivery, the chemical, enzymatic and mucoadhesive barriers within the gastrointestinal (GI) tract must be analyzed. This will allow for the nanomaterials to cross these barriers and reach the colon. This review provides information on the development of nanoparticles made from various polysaccharides, which can overcome multiple barriers along the GI tract and affect encapsulation efficiency, drug protection, and release mechanisms upon arrival in the colon. Also, there is information disclosed about the size of the nanoparticles that are usually involved in the mechanisms of diffusion through the barriers in the GI tract, which may influence early drug degradation and release in the digestive tract.
Yubia De Anda-Flores; Elizabeth Carvajal-Millan; Alma Campa-Mada; Jaime Lizardi-Mendoza; Agustin Rascon-Chu; Judith Tanori-Cordova; Ana Martínez-López. Polysaccharide-Based Nanoparticles for Colon-Targeted Drug Delivery Systems. Polysaccharides 2021, 2, 626 -647.
AMA StyleYubia De Anda-Flores, Elizabeth Carvajal-Millan, Alma Campa-Mada, Jaime Lizardi-Mendoza, Agustin Rascon-Chu, Judith Tanori-Cordova, Ana Martínez-López. Polysaccharide-Based Nanoparticles for Colon-Targeted Drug Delivery Systems. Polysaccharides. 2021; 2 (3):626-647.
Chicago/Turabian StyleYubia De Anda-Flores; Elizabeth Carvajal-Millan; Alma Campa-Mada; Jaime Lizardi-Mendoza; Agustin Rascon-Chu; Judith Tanori-Cordova; Ana Martínez-López. 2021. "Polysaccharide-Based Nanoparticles for Colon-Targeted Drug Delivery Systems." Polysaccharides 2, no. 3: 626-647.
Nanoparticles based on chitosan modified with epigallocatechin gallate (EGCG) were synthetized by nanoprecipitation (EGCG-g-chitosan-P). Chitosan was modified by free-radical-induced grafting, which was verified by Fourier transform infrared (FTIR). Furthermore, the morphology, particle size, polydispersity index, and zeta potential of the nanoparticles were investigated. The grafting degree of EGCG, reactive oxygen species (ROS) production, antibacterial and antioxidant activities of EGCG-g-chitosan-P were evaluated and compared with those of pure EGCG and chitosan nanoparticles (Chitosan-P). FTIR results confirmed the modification of the chitosan with EGCG. The EGCG-g-chitosan-P showed spherical shapes and smoother surfaces than those of Chitosan-P. EGCG content of the grafted chitosan nanoparticles was 330 μg/g. Minimal inhibitory concentration (MIC) of EGCG-g-chitosan-P (15.6 μg/mL) was lower than Chitosan-P (31.2 μg/mL) and EGCG (500 μg/mL) against Pseudomonas fluorescens (p < 0.05). Additionally, EGCG-g-chitosan-P and Chitosan-P presented higher Staphylococcus aureus growth inhibition (100%) than EGCG at the lowest concentration tested. The nanoparticles produced an increase of ROS (p < 0.05) in both bacterial species assayed. Furthermore, EGCG-g-chitosan-P exhibited higher antioxidant activity than that of Chitosan-P (p < 0.05) in 2,2′-azino-bis (3-ethyl-benzothiazoline-6-sulfonic acid) (ABTS), 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) and ferric-reducing antioxidant power assays. Based on the above results, EGCG-g-chitosan-P shows the potential for food packaging and biomedical applications.
María Moreno-Vásquez; Maribel Plascencia-Jatomea; Saúl Sánchez-Valdes; Judith Tanori-Córdova; Francisco Castillo-Yañez; Idania Quintero-Reyes; Abril Graciano-Verdugo. Characterization of Epigallocatechin-Gallate-Grafted Chitosan Nanoparticles and Evaluation of Their Antibacterial and Antioxidant Potential. Polymers 2021, 13, 1375 .
AMA StyleMaría Moreno-Vásquez, Maribel Plascencia-Jatomea, Saúl Sánchez-Valdes, Judith Tanori-Córdova, Francisco Castillo-Yañez, Idania Quintero-Reyes, Abril Graciano-Verdugo. Characterization of Epigallocatechin-Gallate-Grafted Chitosan Nanoparticles and Evaluation of Their Antibacterial and Antioxidant Potential. Polymers. 2021; 13 (9):1375.
Chicago/Turabian StyleMaría Moreno-Vásquez; Maribel Plascencia-Jatomea; Saúl Sánchez-Valdes; Judith Tanori-Córdova; Francisco Castillo-Yañez; Idania Quintero-Reyes; Abril Graciano-Verdugo. 2021. "Characterization of Epigallocatechin-Gallate-Grafted Chitosan Nanoparticles and Evaluation of Their Antibacterial and Antioxidant Potential." Polymers 13, no. 9: 1375.
Laura G Ceballos-Mendivil; Yannely Carvajal-Campos; Judith Tánori-Córdova; Jonathan C Luque-Ceballos; Heidi Villafán-Vidales; Claudio A Estrada. Solar synthesis of nanostructured zirconia: microstructural and thermal characterization. Materials Research Express 2020, 7, 115014 .
AMA StyleLaura G Ceballos-Mendivil, Yannely Carvajal-Campos, Judith Tánori-Córdova, Jonathan C Luque-Ceballos, Heidi Villafán-Vidales, Claudio A Estrada. Solar synthesis of nanostructured zirconia: microstructural and thermal characterization. Materials Research Express. 2020; 7 (11):115014.
Chicago/Turabian StyleLaura G Ceballos-Mendivil; Yannely Carvajal-Campos; Judith Tánori-Córdova; Jonathan C Luque-Ceballos; Heidi Villafán-Vidales; Claudio A Estrada. 2020. "Solar synthesis of nanostructured zirconia: microstructural and thermal characterization." Materials Research Express 7, no. 11: 115014.
The purpose of this investigation was to extract ferulated arabinoxylans (AX) from dried distillers’ grains with solubles (DDGS) plus to investigate their capability to form covalently cross-linked nanoparticles. AX registered 7.3 µg of ferulic acid/mg polysaccharide and molecular weight and intrinsic viscosity of 661 kDa and 149 mL/g, correspondingly. Fourier transform infrared spectroscopy (FTIR) was used to confirm the identity of this polysaccharide. AX formed laccase induced covalent gels at 1% (w/v), which registered an elastic modulus of 224 Pa and a content of FA dimers of 1.5 µg/mg polysaccharide. Scanning electron microscopy pictures of AX gels exhibited a microstructure resembling a rough honeycomb. AX formed covalently cross-linked nanoparticles (NAX) by coaxial electrospray. The average hydrodynamic diameter of NAX determined by dynamic light scattering was 328 nm. NAX presented a spherical and regular shape by transmission electron microscopy analysis. NAX may be an attractive material for pharmaceutical and biomedical applications and an option in sustainable DDGS use.
Yubia De Anda-Flores; Elizabeth Carvajal-Millan; Jaime Lizardi-Mendoza; Agustin Rascon-Chu; Ana Luisa Martínez-López; Jorge Marquez-Escalante; Francisco Brown-Bojorquez; Judith Tanori-Cordova. Covalently Cross-Linked Nanoparticles Based on Ferulated Arabinoxylans Recovered from a Distiller’s Dried Grains Byproduct. Processes 2020, 8, 1 .
AMA StyleYubia De Anda-Flores, Elizabeth Carvajal-Millan, Jaime Lizardi-Mendoza, Agustin Rascon-Chu, Ana Luisa Martínez-López, Jorge Marquez-Escalante, Francisco Brown-Bojorquez, Judith Tanori-Cordova. Covalently Cross-Linked Nanoparticles Based on Ferulated Arabinoxylans Recovered from a Distiller’s Dried Grains Byproduct. Processes. 2020; 8 (6):1.
Chicago/Turabian StyleYubia De Anda-Flores; Elizabeth Carvajal-Millan; Jaime Lizardi-Mendoza; Agustin Rascon-Chu; Ana Luisa Martínez-López; Jorge Marquez-Escalante; Francisco Brown-Bojorquez; Judith Tanori-Cordova. 2020. "Covalently Cross-Linked Nanoparticles Based on Ferulated Arabinoxylans Recovered from a Distiller’s Dried Grains Byproduct." Processes 8, no. 6: 1.
In this article, a synthesis of the compound In2O3–TiO2–Al2O3 (molar relation 3:4:1 and 5:8:1) at 1350 °C by solid-state reactions is described. The compounds were obtained after heat treatment at 1350 °C for two days. X-ray diffraction patterns indicate that the synthesized samples belong to the monoclinic crystal system with the space group C 2/m. An agglomeration of the crystals was observed by scanning electron microscopy for the heat-treated samples of either composition (S1HT and S2HT). Atomic quantitative analysis showed variations of the two compositions presented and TEM analyses confirmed that In3Ti2AlO10 crystals were formed. Partial nanocrystallization and irregularities can be observed in the micrographs. Both samples were polymorphic and presented chain discontinuities attributed to oxygen vacancies and/or distortions in the structure. UV–vis measurements were performed obtaining a band gap ~ 3.2 eV for all the samples analyzed. XPS analysis for S1HT and S2HT confirmed the expected oxidation of the compounds.
C. L. Medrano-Pesqueira; Francisco Brown; Doris Möncke; Dominique De Ligny; Judith Tanori; T. Del Castillo-Castro. Structural and optical characterization of crystals obtained via solid state reactions in the In2O3–TiO2–Al2O3 pseudoternary system. SN Applied Sciences 2019, 1, 502 .
AMA StyleC. L. Medrano-Pesqueira, Francisco Brown, Doris Möncke, Dominique De Ligny, Judith Tanori, T. Del Castillo-Castro. Structural and optical characterization of crystals obtained via solid state reactions in the In2O3–TiO2–Al2O3 pseudoternary system. SN Applied Sciences. 2019; 1 (5):502.
Chicago/Turabian StyleC. L. Medrano-Pesqueira; Francisco Brown; Doris Möncke; Dominique De Ligny; Judith Tanori; T. Del Castillo-Castro. 2019. "Structural and optical characterization of crystals obtained via solid state reactions in the In2O3–TiO2–Al2O3 pseudoternary system." SN Applied Sciences 1, no. 5: 502.
Engineering of multifunctional drug nanocarriers combining stability and good release properties remains a great challenge. In this work, natural polymers κ-carrageenan (κ-CAR) and chitosan (CS) were deposited onto olive oil nanoemulsion droplets (NE) via layer-by-layer (LbL) self-assembly to study the release mechanisms of the anti-inflammatory diflunisal (DF) as a lipophilic drug model. The nano-systems were characterized by dynamic light scattering (DLS), zeta potential (ζ-potential) measurements, transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray energy dispersive spectroscopy (XEDS) and Fourier transform infrared spectroscopy (FTIR) to confirm the NE-coating with polymer layers. In addition, kinetic release studies of DF were developed by the dialysis diffusion bag technique. Mathematical models were applied to investigate the release mechanisms. The results showed that stable and suitably sized nanocapsules (~300 nm) were formed. Also, the consecutive adsorption of polyelectrolytes by charge reversal was evidenced. More interestingly, the drug release mechanism varied depending on the number of layers deposited. The nanosized systems containing up to two layers showed anomalous transport and first order kinetics. Formulations with three and four layers exhibited Case II transport releasing diflunisal with zero order kinetics. Hence, our results suggest that these polyelectrolyte nanocapsules have great potential as a multifunctional nanocarrier for drug delivery applications.
Sarai Rochín-Wong; Aarón Rosas-Durazo; Paul Zavala-Rivera; Amir Maldonado; María Elisa Martínez-Barbosa; Itziar Vélaz; Judith Tánori. Drug Release Properties of Diflunisal from Layer-By-Layer Self-Assembled κ-Carrageenan/Chitosan Nanocapsules: Effect of Deposited Layers. Polymers 2018, 10, 760 .
AMA StyleSarai Rochín-Wong, Aarón Rosas-Durazo, Paul Zavala-Rivera, Amir Maldonado, María Elisa Martínez-Barbosa, Itziar Vélaz, Judith Tánori. Drug Release Properties of Diflunisal from Layer-By-Layer Self-Assembled κ-Carrageenan/Chitosan Nanocapsules: Effect of Deposited Layers. Polymers. 2018; 10 (7):760.
Chicago/Turabian StyleSarai Rochín-Wong; Aarón Rosas-Durazo; Paul Zavala-Rivera; Amir Maldonado; María Elisa Martínez-Barbosa; Itziar Vélaz; Judith Tánori. 2018. "Drug Release Properties of Diflunisal from Layer-By-Layer Self-Assembled κ-Carrageenan/Chitosan Nanocapsules: Effect of Deposited Layers." Polymers 10, no. 7: 760.
Polyethylene glycol (PEG) molecules act as a reducing and stabilizing agent in the formation of silver nanoparticles. PEG undergoes thermal oxidative degradation at temperatures over 70 °C in the presence of oxygen. Here, we studied how the temperature and an oxidizing atmosphere could affect the synthesis of silver nanoparticles with PEG. We tested different AgNO3 concentrations for nanoparticles syntheses using PEG of low molecular weight, at 60 and 100 °C. At the higher temperature, the reducing action of PEG increased and the effect of PEG/Ag+ ratio on nanoparticles aggregation changed. These results suggest that different synthesis mechanisms operate at 60 and 100 °C. Thus, at 60 °C the reduction of silver ions can occur through the oxidation of the hydroxyl groups of PEG, as has been previously reported. We propose that the thermal oxidative degradation of PEG at 100 °C increases the number of both, functional groups and molecules that can reduce silver ions and stabilize silver nanoparticles. This degradation process could explain the enhancement of PEG reducing action observed by other authors when they increase the reaction temperature or use a PEG of higher molecular weight
Noralvis Fleitas-Salazar; Erika Silva-Campa; Seidy Pedroso-Santana; Judith Tanori; Martín R. Pedroza-Montero; Raúl Riera. Effect of temperature on the synthesis of silver nanoparticles with polyethylene glycol: new insights into the reduction mechanism. Journal of Nanoparticle Research 2017, 19, 113 .
AMA StyleNoralvis Fleitas-Salazar, Erika Silva-Campa, Seidy Pedroso-Santana, Judith Tanori, Martín R. Pedroza-Montero, Raúl Riera. Effect of temperature on the synthesis of silver nanoparticles with polyethylene glycol: new insights into the reduction mechanism. Journal of Nanoparticle Research. 2017; 19 (3):113.
Chicago/Turabian StyleNoralvis Fleitas-Salazar; Erika Silva-Campa; Seidy Pedroso-Santana; Judith Tanori; Martín R. Pedroza-Montero; Raúl Riera. 2017. "Effect of temperature on the synthesis of silver nanoparticles with polyethylene glycol: new insights into the reduction mechanism." Journal of Nanoparticle Research 19, no. 3: 113.
Self-assembling systems of amphiphilic molecules display structures similar to those of biomineralization natural systems. This allows to somehow mimic nature to synthesize nanomaterials with low polidispersity and with diverse morphologies. In this work we describe the synthesis and characterization of gold-copper, silver-copper, and gold-silver bimetallic nanoparticles by chemical reduction in self-assembling systems of two surfactants. The nanoparticles were characterized by Transmission Electron Microscopy and UV-Vis spectroscopy. We have prepared a composite material using mesoporous silica as support of the AuAg bimetallic nanoparticles. The system was used in photocatalysis experiments for water remediation applications. Our results show that the AuAg/SBA15 composite material degrades methyl orange in water from 17 ppm to 4 ppm in 30 minutes.
Judith Tanori; Diana Vargas-Hernández; María Elisa Martínez-Barbosa; Raul Borja-Urby; Arturo García-Bórquez; Jesús Arenas-Alatorre; Amir Maldonado. AuCu, AgCu and AuAg Bimetallic Nanoparticles: Synthesis, Characterization and Water Remediation. MRS Advances 2016, 1, 2525 -2530.
AMA StyleJudith Tanori, Diana Vargas-Hernández, María Elisa Martínez-Barbosa, Raul Borja-Urby, Arturo García-Bórquez, Jesús Arenas-Alatorre, Amir Maldonado. AuCu, AgCu and AuAg Bimetallic Nanoparticles: Synthesis, Characterization and Water Remediation. MRS Advances. 2016; 1 (36):2525-2530.
Chicago/Turabian StyleJudith Tanori; Diana Vargas-Hernández; María Elisa Martínez-Barbosa; Raul Borja-Urby; Arturo García-Bórquez; Jesús Arenas-Alatorre; Amir Maldonado. 2016. "AuCu, AgCu and AuAg Bimetallic Nanoparticles: Synthesis, Characterization and Water Remediation." MRS Advances 1, no. 36: 2525-2530.
En este trabajo se describe de manera general la importancia de la cristalización de proteínas para realizar experimentos de difracción de rayos X que permitan dilucidar la estructura terciaria de dichas biomoléculas. En particular, se expone que la cristalización de proteínas de membrana requiere métodos especiales de preparación de la matriz de cristalización puesto que se debe “mimetizar” el ambiente hidrofóbico de la proteína en la membrana. De esta manera, el trabajo se centra en algunas propiedades de la fase líquida de membranas denominada “fase esponja”, cuya característica principal es una estructura membranar compleja conectada en tres dimensiones. Debido a su microestructura, la fase esponja es transparente e isotrópica, además de presentar baja viscosidad en las membranas. Estas características convierten a la fase esponja en un medio “biomimético” potencialmente útil para cristalizar proteínas de membrana.
Amir Darío Maldonado Arce; Ramón Íñiguez Palomares; Ricardo López Esparza; Gerardo Paredes Quijada; Judith Tánori Córdova. LA FASE ESPONJA COMO SISTEMA BIOMIMÉTICO PARA CRISTALIZAR PROTEÍNAS DE MEMBRANA. EPISTEMUS 2016, 10, 21 -26.
AMA StyleAmir Darío Maldonado Arce, Ramón Íñiguez Palomares, Ricardo López Esparza, Gerardo Paredes Quijada, Judith Tánori Córdova. LA FASE ESPONJA COMO SISTEMA BIOMIMÉTICO PARA CRISTALIZAR PROTEÍNAS DE MEMBRANA. EPISTEMUS. 2016; 10 (20):21-26.
Chicago/Turabian StyleAmir Darío Maldonado Arce; Ramón Íñiguez Palomares; Ricardo López Esparza; Gerardo Paredes Quijada; Judith Tánori Córdova. 2016. "LA FASE ESPONJA COMO SISTEMA BIOMIMÉTICO PARA CRISTALIZAR PROTEÍNAS DE MEMBRANA." EPISTEMUS 10, no. 20: 21-26.
We have synthesized silver nanoparticles in the non-polar phase of non-aqueous microemulsions. The nanocrystals have been grown by reducing silver ions in the microemulsion cylindrical micelles formed by the reducing agent (ethylene glycol). By a careful deposit of the microemulsion phase on a substrate, the micelles align in a hexagonal geometry, thus forming a 2D array of parallel strings of individual silver nanoparticles on the substrate. The microemulsions are the ternary system of anionic surfactant, non-polar solvent (isooctane), and solvent polar (ethylene glycol); the size of synthesized nanoparticles is about 7 nm and they are monodisperse. The study of the microstructure was realized by transmission electron microscopy, high-resolution technique transmission electron microscopy (HR-TEM), and Fourier processing using the software Digital Micrograph for the determination of the crystalline structure of the HR-TEM images of the nanocrystals; chemical composition was determined using the energy-dispersive X-ray spectroscopy. Addition technique polarizing light microscopy allowed the observation of the hexagonal phase of the system. This method of synthesis and self-alignment could be useful for the preparation of patterned materials at the nanometer scale.
Ericka Rodríguez-León; Ramón Iñiguez-Palomares; Efrain Urrutia-Banuelos; Ronaldo Herrera-Urbina; Judith Tánori; Amir Maldonado. Self-alignment of silver nanoparticles in highly ordered 2D arrays. nano Online 2016, 1 .
AMA StyleEricka Rodríguez-León, Ramón Iñiguez-Palomares, Efrain Urrutia-Banuelos, Ronaldo Herrera-Urbina, Judith Tánori, Amir Maldonado. Self-alignment of silver nanoparticles in highly ordered 2D arrays. nano Online. 2016; ():1.
Chicago/Turabian StyleEricka Rodríguez-León; Ramón Iñiguez-Palomares; Efrain Urrutia-Banuelos; Ronaldo Herrera-Urbina; Judith Tánori; Amir Maldonado. 2016. "Self-alignment of silver nanoparticles in highly ordered 2D arrays." nano Online , no. : 1.
Silicon carbide (SiC) has been prepared successfully using concentrated solar energy provided by the IER-UNAM solar furnace. This has led to the development of a low CO2 emissions process for the production of this material via carbothermic reduction of a silica/carbon (SiO2/C) nanocomposite, which has shown a more reactive carbon for formation of composite, being more thermally stable. Silica (obtained by a sol–gel process) and sucrose were used as precursors of silicon and carbon, respectively, at a temperature of 700 °C in controlled atmosphere (nitrogen) for the formation of the SiO2/C composite. This composite was used in a second step to obtain SiC at a temperature of 1500 °C, in argon atmosphere. The experimental setup used a Pyrex® glass spherical vessel designed to work with concentrated solar power and controlled atmospheres. The structure and morphology of the solar obtained SiC were analyzed with FTIR, XRD, TGA/DSC, SEM and TEM techniques. Results show that it is feasible to use concentrated solar energy for the synthesis of SiC. The solar SiC obtained is nanostructured and is mainly β-SiC.
L.G. Ceballos-Mendivil; Rafael Enrique Cabanillas Lopez; Judith Tanori; R. Murrieta-Yescas; Carlos Pérez-Rábago; H.I. Villafán-Vidales; Camilo A. Arancibia Bulnes; C.A. Estrada. Synthesis of silicon carbide using concentrated solar energy. Solar Energy 2015, 116, 238 -246.
AMA StyleL.G. Ceballos-Mendivil, Rafael Enrique Cabanillas Lopez, Judith Tanori, R. Murrieta-Yescas, Carlos Pérez-Rábago, H.I. Villafán-Vidales, Camilo A. Arancibia Bulnes, C.A. Estrada. Synthesis of silicon carbide using concentrated solar energy. Solar Energy. 2015; 116 ():238-246.
Chicago/Turabian StyleL.G. Ceballos-Mendivil; Rafael Enrique Cabanillas Lopez; Judith Tanori; R. Murrieta-Yescas; Carlos Pérez-Rábago; H.I. Villafán-Vidales; Camilo A. Arancibia Bulnes; C.A. Estrada. 2015. "Synthesis of silicon carbide using concentrated solar energy." Solar Energy 116, no. : 238-246.
We have synthesized silver nanoparticles in the non-polar phase of non-aqueous microemulsions. The nanocrystals have been grown by reducing silver ions in the microemulsion cylindrical micelles formed by the reducing agent (ethylene glycol). By a careful deposit of the microemulsion phase on a substrate, the micelles align in a hexagonal geometry, thus forming a 2D array of parallel strings of individual silver nanoparticles on the substrate. The microemulsions are the ternary system of anionic surfactant, non-polar solvent (isooctane), and solvent polar (ethylene glycol); the size of synthesized nanoparticles is about 7 nm and they are monodisperse. The study of the microstructure was realized by transmission electron microscopy, high-resolution technique transmission electron microscopy (HR-TEM), and Fourier processing using the software Digital Micrograph for the determination of the crystalline structure of the HR-TEM images of the nanocrystals; chemical composition was determined using the energy-dispersive X-ray spectroscopy. Addition technique polarizing light microscopy allowed the observation of the hexagonal phase of the system. This method of synthesis and self-alignment could be useful for the preparation of patterned materials at the nanometer scale.
Ericka Rodríguez-León; Ramón Íñiguez-Palomares; Efraín Urrutia-Bañuelos; Ronaldo Herrera-Urbina; Judith Tánori; Amir Maldonado. Self-alignment of silver nanoparticles in highly ordered 2D arrays. Nanoscale Research Letters 2015, 10, 101 -101.
AMA StyleEricka Rodríguez-León, Ramón Íñiguez-Palomares, Efraín Urrutia-Bañuelos, Ronaldo Herrera-Urbina, Judith Tánori, Amir Maldonado. Self-alignment of silver nanoparticles in highly ordered 2D arrays. Nanoscale Research Letters. 2015; 10 (1):101-101.
Chicago/Turabian StyleEricka Rodríguez-León; Ramón Íñiguez-Palomares; Efraín Urrutia-Bañuelos; Ronaldo Herrera-Urbina; Judith Tánori; Amir Maldonado. 2015. "Self-alignment of silver nanoparticles in highly ordered 2D arrays." Nanoscale Research Letters 10, no. 1: 101-101.
The use of ceramic surfaces for thermal solar concentrators are not new, but the high costs of fabrication and limited thermal properties have banned the application of such at large scale. Silicon carbide (SiC) is well known due to its high thermo-mechanical properties and spectral absorbance. Because of its capacities to enhance the energy transfer and its resistance to high temperatures silicon carbide have been recognized in our group as a possible improvement to increase the efficiency of electric energy production. At nano-scale SiC shows high surface area and porosity that could be tuned, making it a state-of-the-art material to be used in the application of thermal solar receptors in “Central Tower” power plants. Although the advantages are favorable, the high temperature needs for its synthesis have been an issue for its spread. In the present work, we introduce a novel method to synthesize SiC powders at lower temperature (650 °C) we present also its characterization for the potential application in the concentration of thermal solar energy at high temperatures.
L.G. Ceballos-Mendivil; R.E. Cabanillas-López; J.C. Tánori-Córdova; R. Murrieta-Yescas; Paul Zavala-Rivera; J.H. Castorena González. Synthesis and Characterization of Silicon Carbide in the Application of High Temperature Solar Surface Receptors. Energy Procedia 2014, 57, 533 -540.
AMA StyleL.G. Ceballos-Mendivil, R.E. Cabanillas-López, J.C. Tánori-Córdova, R. Murrieta-Yescas, Paul Zavala-Rivera, J.H. Castorena González. Synthesis and Characterization of Silicon Carbide in the Application of High Temperature Solar Surface Receptors. Energy Procedia. 2014; 57 ():533-540.
Chicago/Turabian StyleL.G. Ceballos-Mendivil; R.E. Cabanillas-López; J.C. Tánori-Córdova; R. Murrieta-Yescas; Paul Zavala-Rivera; J.H. Castorena González. 2014. "Synthesis and Characterization of Silicon Carbide in the Application of High Temperature Solar Surface Receptors." Energy Procedia 57, no. : 533-540.
In this work, experimental results for the enhancement of the thermal diffusivity of a colloidal suspension of gold nanoparticles in biodiesel oil are reported. Different concentrations of Au nanoparticles are prepared using a microemulsion method, by simultaneous reduction of Au ions in the presence of hydrazine as a reducing agent. The thermal diffusivity was found to increase with increasing nanoparticle concentration.
J. L. Jiménez-Pérez; R. Gutierrez Fuentes; Z. N. Correa-Pacheco; J. Tánori-Cordova; A. Cruz-Orea; G. López Gamboa. Study of Vegetable Biodiesel Enhanced by Gold Nanoparticles Using Thermal-Lens Technique. International Journal of Thermophysics 2014, 36, 1086 -1092.
AMA StyleJ. L. Jiménez-Pérez, R. Gutierrez Fuentes, Z. N. Correa-Pacheco, J. Tánori-Cordova, A. Cruz-Orea, G. López Gamboa. Study of Vegetable Biodiesel Enhanced by Gold Nanoparticles Using Thermal-Lens Technique. International Journal of Thermophysics. 2014; 36 (5-6):1086-1092.
Chicago/Turabian StyleJ. L. Jiménez-Pérez; R. Gutierrez Fuentes; Z. N. Correa-Pacheco; J. Tánori-Cordova; A. Cruz-Orea; G. López Gamboa. 2014. "Study of Vegetable Biodiesel Enhanced by Gold Nanoparticles Using Thermal-Lens Technique." International Journal of Thermophysics 36, no. 5-6: 1086-1092.
We have synthesized silver nanoparticles from silver nitrate solutions using extracts of Rumex hymenosepalus, a plant widely found in a large region in North America, as reducing agent. This plant is known to be rich in antioxidant molecules which we use as reducing agents. Silver nanoparticles grow in a single-step method, at room temperature, and with no addition of external energy. The nanoparticles have been characterized by ultraviolet-visible spectroscopy and transmission electron microscopy, as a function of the ratio of silver ions to reducing agent molecules. The nanoparticle diameters are in the range of 2 to 40 nm. High-resolution transmission electron microscopy and fast Fourier transform analysis show that two kinds of crystal structures are obtained: face-centered cubic and hexagonal.
Ericka Rodríguez-León; Ramón Iñiguez-Palomares; Rosa Elena Navarro; Ronaldo Herrera-Urbina; Judith Tánori; Claudia Iñiguez-Palomares; Amir Maldonado. Synthesis of silver nanoparticles using reducing agents obtained from natural sources (Rumex hymenosepalus extracts). Nanoscale Research Letters 2013, 8, 318 -318.
AMA StyleEricka Rodríguez-León, Ramón Iñiguez-Palomares, Rosa Elena Navarro, Ronaldo Herrera-Urbina, Judith Tánori, Claudia Iñiguez-Palomares, Amir Maldonado. Synthesis of silver nanoparticles using reducing agents obtained from natural sources (Rumex hymenosepalus extracts). Nanoscale Research Letters. 2013; 8 (1):318-318.
Chicago/Turabian StyleEricka Rodríguez-León; Ramón Iñiguez-Palomares; Rosa Elena Navarro; Ronaldo Herrera-Urbina; Judith Tánori; Claudia Iñiguez-Palomares; Amir Maldonado. 2013. "Synthesis of silver nanoparticles using reducing agents obtained from natural sources (Rumex hymenosepalus extracts)." Nanoscale Research Letters 8, no. 1: 318-318.
Palladium-gold core-shell nanoparticles were synthesized in the aqueous domains of water in oil microemulsions by the sequential reduction of H2PdCl4 and HAuCl4. The nanoparticles were characterized by ultraviolet-visible (UV-vis) spectroscopy and transmission electron microscopy (TEM). The UV-vis spectra confirm the presence of palladium nanoparticles after reducing H2PdCl4. These particles have been used as seeds for the core-shell particles. UV-vis spectra show that, after reducing HAuCl4, the surface plasmon absorption of the nanoparticles is dominated by gold, revealing the encapsulation of the palladium seeds. These results agree with crystallographic analysis performed with high-resolution TEM pictures, as well as with selected area electron diffraction. The TEM pictures show the core-shell nanoparticles with an average diameter of 9.1 nm, as compared with 5 nm for the palladium seeds, in good agreement with the used Pd:Au molar ratio.
Eduardo Larios; Lilián Calderón; Karen Guerrero; Emanuel Pinedo; Amir Maldonado; Judith Tanori. Synthesis of Core-Shell (Pd-Au) Bimetallic Nanoparticles in Microemulsions. Journal of Dispersion Science and Technology 2012, 33, 1360 -1367.
AMA StyleEduardo Larios, Lilián Calderón, Karen Guerrero, Emanuel Pinedo, Amir Maldonado, Judith Tanori. Synthesis of Core-Shell (Pd-Au) Bimetallic Nanoparticles in Microemulsions. Journal of Dispersion Science and Technology. 2012; 33 (9):1360-1367.
Chicago/Turabian StyleEduardo Larios; Lilián Calderón; Karen Guerrero; Emanuel Pinedo; Amir Maldonado; Judith Tanori. 2012. "Synthesis of Core-Shell (Pd-Au) Bimetallic Nanoparticles in Microemulsions." Journal of Dispersion Science and Technology 33, no. 9: 1360-1367.
We have synthesized copper-gold, core-shell nanoparticles by the microemulsion method. The particles were prepared in two steps, by first reducing copper ions and then gold ions in the aqueous domains of anionic microemulsions. Two surfactants have been used as emulsifiers, AOT and Cu(AOT)2. The latter is the source of copper ions. Gold ions come from aqueous solutions of HAuCl4. Ultraviolet-visible spectroscopy experiments show that copper nanoparticles are created in the first step of the synthesis, and that a gold layer covers them in the second step. Transmission electron microscopy and related techniques confirm the formation of copper (core)-gold (shell) nanocrystals.
Eduardo Larios; Zulema Molina; Amir Maldonado; Judith Tanori. Synthesis and Characterization of Bimetallic Copper-Gold Nanoparticles. Journal of Dispersion Science and Technology 2012, 33, 719 -723.
AMA StyleEduardo Larios, Zulema Molina, Amir Maldonado, Judith Tanori. Synthesis and Characterization of Bimetallic Copper-Gold Nanoparticles. Journal of Dispersion Science and Technology. 2012; 33 (5):719-723.
Chicago/Turabian StyleEduardo Larios; Zulema Molina; Amir Maldonado; Judith Tanori. 2012. "Synthesis and Characterization of Bimetallic Copper-Gold Nanoparticles." Journal of Dispersion Science and Technology 33, no. 5: 719-723.
J.L. Jiménez-Pérez; R. Gutierrez Fuentes; E. Maldonado Alvarado; E. Ramón-Gallegos; A. Cruz-Orea; J. Tánori-Cordova; J.G. Mendoza-Alvarez. Enhancement of the thermal transport in a culture medium with Au nanoparticles. Applied Surface Science 2008, 255, 701 -702.
AMA StyleJ.L. Jiménez-Pérez, R. Gutierrez Fuentes, E. Maldonado Alvarado, E. Ramón-Gallegos, A. Cruz-Orea, J. Tánori-Cordova, J.G. Mendoza-Alvarez. Enhancement of the thermal transport in a culture medium with Au nanoparticles. Applied Surface Science. 2008; 255 (3):701-702.
Chicago/Turabian StyleJ.L. Jiménez-Pérez; R. Gutierrez Fuentes; E. Maldonado Alvarado; E. Ramón-Gallegos; A. Cruz-Orea; J. Tánori-Cordova; J.G. Mendoza-Alvarez. 2008. "Enhancement of the thermal transport in a culture medium with Au nanoparticles." Applied Surface Science 255, no. 3: 701-702.
The use of gold nanoparticles (np‐Au) to eliminate cancer has proved to be very effective due to the fact that cancerous cells accumulate it 600% more than healthy cells. In addition they have a high capacity of absorption and dispersion of light. Therefore, the effectiveness of photodynamic therapy (PDT) could be improved by the simultaneous use of np‐Au and photosensitizes (Ps), emphasizing the high efficiency of the PDT to diagnose and to treat pre‐malignant and malignant processes. The aim of this work was to determine the efficiency of PDT using np‐Au and protoporphyrin IX (PpIX) induced and not induced by the δ‐aminolevulinic acid (ALA). It were found the conditions of synthesis of hydrosoluble np‐Au, and were characterized by transmission electronic microscopy (TEM) and UV‐VIS spectroscopy. It was realized a kinetic by TEM to determine the cellular incorporation time of np‐Au, the maximum incorporation of np‐Au was of 16 h. PDT was applied using different doses of np‐Au and photosensitizers. It was observed that the use of PDT simultaneously with np‐Au did not increase the mortality of HeLa cells. In the case of C33, when PpIX not induced is used as photosensitizer simultaneously with np‐Au, the mortality increased 20%.
Elizabeth Maldonado‐Alvarado; Eva Ramón‐Gallegos; Judith Tánori‐Córdova; Francisco Jesús Arenas‐Huertero; María Esther Sánchez‐Espíndola; Alicia Reyes‐Arellano; José Luis Jiménez‐Pérez; Alfredo Cruz‐Orea. Efficiency Of The Photodynamic Therapy Using Gold Nanoparticles (np-Au) And PpIX Induced And Not Induced. AIP Conference Proceedings 2008, 1032, 295 -298.
AMA StyleElizabeth Maldonado‐Alvarado, Eva Ramón‐Gallegos, Judith Tánori‐Córdova, Francisco Jesús Arenas‐Huertero, María Esther Sánchez‐Espíndola, Alicia Reyes‐Arellano, José Luis Jiménez‐Pérez, Alfredo Cruz‐Orea. Efficiency Of The Photodynamic Therapy Using Gold Nanoparticles (np-Au) And PpIX Induced And Not Induced. AIP Conference Proceedings. 2008; 1032 (1):295-298.
Chicago/Turabian StyleElizabeth Maldonado‐Alvarado; Eva Ramón‐Gallegos; Judith Tánori‐Córdova; Francisco Jesús Arenas‐Huertero; María Esther Sánchez‐Espíndola; Alicia Reyes‐Arellano; José Luis Jiménez‐Pérez; Alfredo Cruz‐Orea. 2008. "Efficiency Of The Photodynamic Therapy Using Gold Nanoparticles (np-Au) And PpIX Induced And Not Induced." AIP Conference Proceedings 1032, no. 1: 295-298.