http://sedici.unlp.edu.ar:80/handle/10915/65470 2026-08-09T17:04:09Z 2026-08-09T17:04:09Z Sanchez, M. V. Baroli, Carlos Manuel Álvarez Hayes, Jimena Gorgojo, Juan Pablo Carrica, M. Lamberti, Yanina Andrea Rodríguez, María Eugenia Valdez, Hugo Alberto http://sedici.unlp.edu.ar:80/handle/10915/197332 2026-08-07T04:42:25Z 2025-01-01T00:00:00Z

Objeto de conferencia XLIII Reunión Científica Anual de la Sociedad de Biología de Cuyo (Mendoza, 4 y 5 de diciembre de 2025) During microbial infections, macrophages (MØ) display remarkable plasticity, transitioning between classically activated (M1) and alternatively activated (M2) phenotypes according to environmental cues. Our group has previously shown that Bordetella pertussis modulates macrophage polarization to favor intracellular persistence. The aim of this study was to evaluate the specific contribution of complement receptor 3 (CR3; CD11b/CD18) and the mannose receptor (CD206) to the adhesion, internalization, and intracellular trafficking of Bordetella pertussis in human monocyte-derived M0 macrophages in a non-polarized state.

2025-01-01T00:00:00Z During microbial infections, macrophages (MØ) display remarkable plasticity, transitioning between classically activated (M1) and alternatively activated (M2) phenotypes according to environmental cues. Our group has previously shown that Bordetella pertussis modulates macrophage polarization to favor intracellular persistence. The aim of this study was to evaluate the specific contribution of complement receptor 3 (CR3; CD11b/CD18) and the mannose receptor (CD206) to the adhesion, internalization, and intracellular trafficking of Bordetella pertussis in human monocyte-derived M0 macrophages in a non-polarized state. Accorinti, C. Germanó, M. J. Valerio, M. Valdez, Hugo Alberto Mackern Oberti, J. P. Cargnelutti, D. E. Sanchez, M. V. http://sedici.unlp.edu.ar:80/handle/10915/197331 2026-08-07T04:42:25Z 2025-01-01T00:00:00Z

Objeto de conferencia XLIII Reunión Científica Anual de la Sociedad de Biología de Cuyo (Mendoza, 4 y 5 de diciembre de 2025) Influenza is a respiratory disease of major global health concern due to its high mutation rate. Current vaccines often show limited efficacy and fail to induce robust and long-lasting immunity. Furthermore, the continuous emergence of new strains with pandemic potential, underscores the urgent need for more effective vaccines developed under a One Health approach. A promising strategy involves the use of conserved antigens combined with innovative adjuvants to improve the breadth and durability of immune protection. The aim of this study was to evaluate the immunogenicity and protective efficacy of an experimental vaccine based on the influenza nucleoprotein (NP) formulated with oil-based adjuvants widely used in veterinary vaccines, such as Montanides ISA, and a novel combination with the TLR3 agonist Poly(I:C).

2025-01-01T00:00:00Z Influenza is a respiratory disease of major global health concern due to its high mutation rate. Current vaccines often show limited efficacy and fail to induce robust and long-lasting immunity. Furthermore, the continuous emergence of new strains with pandemic potential, underscores the urgent need for more effective vaccines developed under a One Health approach. A promising strategy involves the use of conserved antigens combined with innovative adjuvants to improve the breadth and durability of immune protection. The aim of this study was to evaluate the immunogenicity and protective efficacy of an experimental vaccine based on the influenza nucleoprotein (NP) formulated with oil-based adjuvants widely used in veterinary vaccines, such as Montanides ISA, and a novel combination with the TLR3 agonist Poly(I:C). Alberti, Sebastián http://sedici.unlp.edu.ar:80/handle/10915/197261 2026-08-06T04:25:03Z 2019-01-01T00:00:00Z

Articulo Anales de la Asociación Química Argentina; vol. 106, no. 2 The combination of mesostructured metal oxides as robust platforms and the integration to molecular, polymeric, organometallic or biologically active groups as functional construction blocks has enabled the development of new hybrid materials. The precise localization of this active elements in three- dimensional nanometric scale represents the key for the rational design of intelligent inorganic-organic tailor–made hybrids for specific purposes. Such materials would be of great relevance for a great deal of technological applications as optoelectronics, catalysis, biosensors, molecular sieving or drug delivery. In particular, these hard–soft architectures allowed us to create sophisticated intelligent nanosystems that respond to a variety of external stimuli such as pH, redox potential, molecule concentration, temperature, or light paving the way to what is known as "gating chemistry”. Transduction of these stimuli into a predefined response implies exploiting spatial and physicochemical effects such as charge distribution, equilibria displacements, or steric constraints du to degradation of bulky caps or reconfiguration of macromolecules. These changes allow us to control diffusion and transport of probes or host molecules through channels or porous structures diminishing the gap between synthetic and biological systems. This work aims to briefly show a wide variety of strategies for the design of such sophisticated nanoarchitectures and its potential applications.; La combinación de matrices mesoestructuradas de óxidos inorgánicos y su integración con moléculas, polímeros, complejos organometálicos y grupos activos biológicos como bloques de construcción funcionales ha permitido el desarrollo de nuevos materiales híbridos. El control espacial preciso de estos elementos activos en escalas tridimensionales nanométricas representa la clave para el diseño racional de materiales híbridos inteligentes orgánicos-inorgánicos hechos a medida para fines específicos. Estos materiales serían de gran relevancia para un gran número de aplicaciones tecnológicas como optoelectrónicas, catálisis, biosensores, tamices moleculares o liberación controlada de drogas. En particular, estas arquitecturas sólido-blandas nos han permitido crear sofisticados nanosistemas capaces de responder a estímulos externos como pH, potencial redox, concentración de analitos específicos, temperatura o luz, marcando el camino hacia lo que en la actualidad se conoce como "gating chemistry”. La transducción de dichos estímulos en una respuesta involucra efectos fisicoquímicos como desplazamientos de equilibrio, redistribución de cargas, o limitaciones estéricas provenientes de la reconfiguración de macromoléculas o la degradación de elementos voluminosos. Estos cambios permiten controlar el transporte y la difusión de moléculas huésped o sondas a través de canales o estructuras porosas acercándonos a la posibilidad de mimetizar sistemas biológicos. Este trabajo tiene como objeto mostrar brevemente las diversas estrategias en el diseño de estos sistemas y la motivación detrás de estas complejas nanoarquitecturas.

2019-01-01T00:00:00Z The combination of mesostructured metal oxides as robust platforms and the integration to molecular, polymeric, organometallic or biologically active groups as functional construction blocks has enabled the development of new hybrid materials. The precise localization of this active elements in three- dimensional nanometric scale represents the key for the rational design of intelligent inorganic-organic tailor–made hybrids for specific purposes. Such materials would be of great relevance for a great deal of technological applications as optoelectronics, catalysis, biosensors, molecular sieving or drug delivery. In particular, these hard–soft architectures allowed us to create sophisticated intelligent nanosystems that respond to a variety of external stimuli such as pH, redox potential, molecule concentration, temperature, or light paving the way to what is known as "gating chemistry”. Transduction of these stimuli into a predefined response implies exploiting spatial and physicochemical effects such as charge distribution, equilibria displacements, or steric constraints du to degradation of bulky caps or reconfiguration of macromolecules. These changes allow us to control diffusion and transport of probes or host molecules through channels or porous structures diminishing the gap between synthetic and biological systems. This work aims to briefly show a wide variety of strategies for the design of such sophisticated nanoarchitectures and its potential applications. La combinación de matrices mesoestructuradas de óxidos inorgánicos y su integración con moléculas, polímeros, complejos organometálicos y grupos activos biológicos como bloques de construcción funcionales ha permitido el desarrollo de nuevos materiales híbridos. El control espacial preciso de estos elementos activos en escalas tridimensionales nanométricas representa la clave para el diseño racional de materiales híbridos inteligentes orgánicos-inorgánicos hechos a medida para fines específicos. Estos materiales serían de gran relevancia para un gran número de aplicaciones tecnológicas como optoelectrónicas, catálisis, biosensores, tamices moleculares o liberación controlada de drogas. En particular, estas arquitecturas sólido-blandas nos han permitido crear sofisticados nanosistemas capaces de responder a estímulos externos como pH, potencial redox, concentración de analitos específicos, temperatura o luz, marcando el camino hacia lo que en la actualidad se conoce como "gating chemistry”. La transducción de dichos estímulos en una respuesta involucra efectos fisicoquímicos como desplazamientos de equilibrio, redistribución de cargas, o limitaciones estéricas provenientes de la reconfiguración de macromoléculas o la degradación de elementos voluminosos. Estos cambios permiten controlar el transporte y la difusión de moléculas huésped o sondas a través de canales o estructuras porosas acercándonos a la posibilidad de mimetizar sistemas biológicos. Este trabajo tiene como objeto mostrar brevemente las diversas estrategias en el diseño de estos sistemas y la motivación detrás de estas complejas nanoarquitecturas. Colombo Migliorero, María Belén Bonilla Castañeda, Sandra M. Fernandes, Sergio A. Palermo, Valeria Vázquez, Patricia Graciela Romanelli, Gustavo Pablo http://sedici.unlp.edu.ar:80/handle/10915/197250 2026-08-05T20:20:42Z 2020-01-01T00:00:00Z

Articulo Anales de la Asociación Química Argentina; vol. 107, no. 1 Se reporta la síntesis de nuevos materiales sólidos constituidos por una matriz de sílice, titania y mixta de sílice-titania conteniendo ácido p-sulfónico calix[4]areno en su estructura llevados a cabo mediante la técnica sol-gel. La morfología, composición y características ácidas de los sólidos obtenidos fueron determinadas mediante técnicas de caracterización: difracción de rayos X, espectroscopía infrarroja con transformada de Fourier, titulación potenciométrica, adsorción/desorción de nitrógeno y microscopias electrónicas de barrido y transmisión. Los materiales preparados, gracias a contener en su estructura ácido p-sulfónico calix[4]areno, presentan prometedoras aplicaciones en el campo de la catálisis heterogénea, para la síntesis de compuestos orgánicos.; The synthesis of new solids constituted by a silica, tinania, and silica-titania matrix, containing p-sulfonic acid calix[4]arene is reported. The samples were prepared by the sol-gel process. The morphology, composition and acid characteristics of the obtained solids were elucidated by many techniques, such as X ray diffraction, Fourier transform infrared spectroscopy, potentiometric titration, adsorption/desorption of nitrogen and scanning and transmission electron microscopies. The samples have promising application in the heterogeneous catalysis field, especially in organic synthesis, since they contain p-sulfonic acid calix[4]arene in the structure.

2020-01-01T00:00:00Z Se reporta la síntesis de nuevos materiales sólidos constituidos por una matriz de sílice, titania y mixta de sílice-titania conteniendo ácido p-sulfónico calix[4]areno en su estructura llevados a cabo mediante la técnica sol-gel. La morfología, composición y características ácidas de los sólidos obtenidos fueron determinadas mediante técnicas de caracterización: difracción de rayos X, espectroscopía infrarroja con transformada de Fourier, titulación potenciométrica, adsorción/desorción de nitrógeno y microscopias electrónicas de barrido y transmisión. Los materiales preparados, gracias a contener en su estructura ácido p-sulfónico calix[4]areno, presentan prometedoras aplicaciones en el campo de la catálisis heterogénea, para la síntesis de compuestos orgánicos. The synthesis of new solids constituted by a silica, tinania, and silica-titania matrix, containing p-sulfonic acid calix[4]arene is reported. The samples were prepared by the sol-gel process. The morphology, composition and acid characteristics of the obtained solids were elucidated by many techniques, such as X ray diffraction, Fourier transform infrared spectroscopy, potentiometric titration, adsorption/desorption of nitrogen and scanning and transmission electron microscopies. The samples have promising application in the heterogeneous catalysis field, especially in organic synthesis, since they contain p-sulfonic acid calix[4]arene in the structure. González Baró, Ana Cecilia Barone, Vicente Luis Baran, Enrique José http://sedici.unlp.edu.ar:80/handle/10915/197249 2026-08-06T04:24:54Z 2020-01-01T00:00:00Z

Articulo Anales de la Asociación Química Argentina; vol. 107, no. 1 The two Bi(III) oxalates of the title were synthesized. Their infrared and Raman spectra were recorded and showed relatively similar spectral patterns. The spectra of Bi(OH)C₂O₄ are consistent with their known structural peculiarities. In the case of Bi₂(C₂O₄)₃⋅7H₂O, the spectroscopic analysis is in agreement with presence of highly distorted tetradentate oxalate groups, generating a complex three-dimensional structural arrangement similar to those found in the two related hydrates of known structures, i.e., Bi₂(C₂O₄)₃⋅6H₂O and Bi₂(C₂O₄)₃⋅8H₂O.; Se sintetizaron los dos oxalatos de Bi(III) del título y se registraron sus espectros de infrarrojo y Raman, los que resultaron ser bastante similares en su forma y ordenamiento espectral. Los espectros del Bi(OH)C₂O₄ resultaron consistentes con sus peculiaridades estructurales conocidas. En el caso del Bi₂(C₂O₄)₃⋅7H₂O el análisis espectroscópico está de acuerdo con la presencia de grupos oxalato tetradentados fuertemente distorsionados, que generan un ordenamiento estructural tridimensional muy complejo, similar a los encontrados en los dos hidratos relacionados de estructuras conocidas, esto es, Bi₂(C₂O₄)₃⋅6H₂O y Bi₂(C₂O₄)₃⋅8H₂O.

2020-01-01T00:00:00Z The two Bi(III) oxalates of the title were synthesized. Their infrared and Raman spectra were recorded and showed relatively similar spectral patterns. The spectra of Bi(OH)C₂O₄ are consistent with their known structural peculiarities. In the case of Bi₂(C₂O₄)₃⋅7H₂O, the spectroscopic analysis is in agreement with presence of highly distorted tetradentate oxalate groups, generating a complex three-dimensional structural arrangement similar to those found in the two related hydrates of known structures, i.e., Bi₂(C₂O₄)₃⋅6H₂O and Bi₂(C₂O₄)₃⋅8H₂O. Se sintetizaron los dos oxalatos de Bi(III) del título y se registraron sus espectros de infrarrojo y Raman, los que resultaron ser bastante similares en su forma y ordenamiento espectral. Los espectros del Bi(OH)C₂O₄ resultaron consistentes con sus peculiaridades estructurales conocidas. En el caso del Bi₂(C₂O₄)₃⋅7H₂O el análisis espectroscópico está de acuerdo con la presencia de grupos oxalato tetradentados fuertemente distorsionados, que generan un ordenamiento estructural tridimensional muy complejo, similar a los encontrados en los dos hidratos relacionados de estructuras conocidas, esto es, Bi₂(C₂O₄)₃⋅6H₂O y Bi₂(C₂O₄)₃⋅8H₂O. Torres, María M. Palacios, Daniel González Baró, Ana Cecilia Barone, Vicente Luis Baran, Enrique José http://sedici.unlp.edu.ar:80/handle/10915/197248 2026-08-06T04:24:55Z 2020-01-01T00:00:00Z

Articulo Anales de la Asociación Química Argentina; vol. 107, no. 1 A series of double metal oxalates of stoichiometry MgM(C₂O₄)₂ ⋅ 4H₂O (with M = Mn, Fe, Co, Ni, Zn) have been prepared and characterized. Their structural behavior was investigated by means of X-ray powder diffractometry, showing a strong structural analogy to the so-called β-modification of the related simple oxalate complexes of composition M(C₂O₄)₂⋅2H₂O. The vibrational spectroscopic behavior of these double metal oxalates was investigated by infrared and Raman spectroscopy. The structural and spectroscopic results clearly confirmed the strong structural analogies between this new series of double oxalates and those of MM'(C₂O₄)₂⋅4H₂O, α-MC₂O₄⋅2H₂O, and β-MC₂O₄⋅2H₂O stoichiometry.; Se preparó y caracterizó una serie de oxalatos dobles de estequiometría MgM(C₂O₄)₂ ⋅ 4H₂O (con M = Mn, Fe, Co, Ni, Zn). Su comportamiento estructural fue investigado por medio de difractometría de rayos X en polvos, mostrando una fuerte analogía estructural con la llamada forma-β, de los oxalatos complejos simples de composición M(C₂O₄)₂⋅2H₂O. El comportamiento espectroscópico vibracional de estos oxalatos dobles fue investigado por espectroscopía de infrarrojo y Raman. Los resultados estructurales y espectroscópicos confirmaron claramente las fuertes analogías estructurales existentes entre esta nueva serie de oxalatos dobles y los de estequiometría MM'(C₂O₄)₂⋅4H₂O, α-MC₂O₄⋅2H₂O, and β-MC₂O₄⋅2H₂O.

2020-01-01T00:00:00Z A series of double metal oxalates of stoichiometry MgM(C₂O₄)₂ ⋅ 4H₂O (with M = Mn, Fe, Co, Ni, Zn) have been prepared and characterized. Their structural behavior was investigated by means of X-ray powder diffractometry, showing a strong structural analogy to the so-called β-modification of the related simple oxalate complexes of composition M(C₂O₄)₂⋅2H₂O. The vibrational spectroscopic behavior of these double metal oxalates was investigated by infrared and Raman spectroscopy. The structural and spectroscopic results clearly confirmed the strong structural analogies between this new series of double oxalates and those of MM'(C₂O₄)₂⋅4H₂O, α-MC₂O₄⋅2H₂O, and β-MC₂O₄⋅2H₂O stoichiometry. Se preparó y caracterizó una serie de oxalatos dobles de estequiometría MgM(C₂O₄)₂ ⋅ 4H₂O (con M = Mn, Fe, Co, Ni, Zn). Su comportamiento estructural fue investigado por medio de difractometría de rayos X en polvos, mostrando una fuerte analogía estructural con la llamada forma-β, de los oxalatos complejos simples de composición M(C₂O₄)₂⋅2H₂O. El comportamiento espectroscópico vibracional de estos oxalatos dobles fue investigado por espectroscopía de infrarrojo y Raman. Los resultados estructurales y espectroscópicos confirmaron claramente las fuertes analogías estructurales existentes entre esta nueva serie de oxalatos dobles y los de estequiometría MM'(C₂O₄)₂⋅4H₂O, α-MC₂O₄⋅2H₂O, and β-MC₂O₄⋅2H₂O. Vera, Claudia Cecilia Morales, Jesús M.N. Guauque Torres, María del Pilar Serrano, Mariana Paula Borsarelli, Claudio D. http://sedici.unlp.edu.ar:80/handle/10915/197239 2026-08-06T04:25:03Z 2025-01-01T00:00:00Z

Articulo Redox Biochemistry and Chemistry; vol. 14 A photosensitized oxidative crosslinking of proteins (POCP) reaction was applied in air-saturated phosphate buffer solutions of bovine serum albumin (BSA) to obtain soluble protein nanoparticles of approximately 100 nm in diameter. A royal blue LED was used as the excitation source for the photosensitizer molecule ruthenium (II) 2− tris(2,2′-bipyridyl) dication (Ru(bpy)2+ 3 ), in the presence of the electron acceptor persulfate anion (S2O8 ). The redox quenching products prompted the formation of side-chain tyrosyl radicals, which served as intermediaries in the covalent attachment between proteins, leading to the formation of dityrosine (Tyr2) links. However, the dissolved oxygen competes efficiently with S2O2− 8 to quench the excited photosensitizer, thereby generating singlet molecular oxygen (1O2), which reacts with electron-rich protein residues, which in turn induce an additional oxidative pattern of BSA. Consequently, under air-saturated conditions, the POCP gives rise to a series of oxygen-dependent and -independent reactions, resulting in the protein crosslinking with oxidative modifi­ cations. The esterase-like activity efficacy of BSA oxidized solely by 1O2 and after the formation of oligomeric protein nanoparticles by POCP was reduced by 51 % and 73 %, respectively, as compared with that of the native BSA. The combination of the oxidative degradation of key residues in the active sites and steric impediment due to protein oligomerization was found to be associated with this result.

2025-01-01T00:00:00Z A photosensitized oxidative crosslinking of proteins (POCP) reaction was applied in air-saturated phosphate buffer solutions of bovine serum albumin (BSA) to obtain soluble protein nanoparticles of approximately 100 nm in diameter. A royal blue LED was used as the excitation source for the photosensitizer molecule ruthenium (II) 2− tris(2,2′-bipyridyl) dication (Ru(bpy)2+ 3 ), in the presence of the electron acceptor persulfate anion (S2O8 ). The redox quenching products prompted the formation of side-chain tyrosyl radicals, which served as intermediaries in the covalent attachment between proteins, leading to the formation of dityrosine (Tyr2) links. However, the dissolved oxygen competes efficiently with S2O2− 8 to quench the excited photosensitizer, thereby generating singlet molecular oxygen (1O2), which reacts with electron-rich protein residues, which in turn induce an additional oxidative pattern of BSA. Consequently, under air-saturated conditions, the POCP gives rise to a series of oxygen-dependent and -independent reactions, resulting in the protein crosslinking with oxidative modifi­ cations. The esterase-like activity efficacy of BSA oxidized solely by 1O2 and after the formation of oligomeric protein nanoparticles by POCP was reduced by 51 % and 73 %, respectively, as compared with that of the native BSA. The combination of the oxidative degradation of key residues in the active sites and steric impediment due to protein oligomerization was found to be associated with this result. Sosa, Alexis Alberto Romanelli, Gustavo Pablo Pizzio, Luis René http://sedici.unlp.edu.ar:80/handle/10915/197148 2026-08-04T20:23:36Z 2019-01-01T00:00:00Z

Articulo Anales de la Asociación Química Argentina; vol. 106, no. 1 Los heterociclos están presentes en la mayoría de productos naturales bioactivos y drogas sintéticas, entre otras. Las aminas heterocíclicas son sustancias, muy comunes y tienen muchas propiedades biológicas importantes. Entre estas aminas, encontramos a las quinoxalinas, estas sustancias son de gran interés químico y biológico debido a la versatilidad que poseen, ya que pueden usarse en colorantes, agroquímicos y como bloques de construcción en fármacos, siendo este último uso uno de los más importantes en la química medicinal. Desde su descubrimiento, la síntesis de estos compuestos fue creciendo en interés en la medida que se descubrían sus propiedades, siendo la actividad bilógica una de las más importantes. Motivados con estos antecedentes y la creciente demanda medioambiental de generar nuevas rutas de síntesis que involucren la catálisis heterogénea como punto de partida, en el presente trabajo se reporta la síntesis de 2,3 difenilquinoxalina (DFQ) empleando nanoparticulas de sílice mesoporosa modificadas con ácido tungstofosfórico como catalizador.; Heterocycles are present in most bioactive natural products and synthetic drugs, among others. Heterocyclic amines are substances, very common and have many important biological properties. Among these amines, we find quinoxalines, these substances are of great chemical and biological interest due to the versatility they possess, since they can be used in dyes, agrochemicals and as building blocks in drugs, the latter being one of the most important in medicinal chemistry. Since its discovery, the synthesis of these compounds was growing in interest as their properties were discovered, being the biological activity one of the most important. Motivated by this background and the growing environmental demand to generate new synthetic routes that involve heterogeneous catalysis as a starting point, in this work we report the synthesis of 2,3 diphenylquinoxaline (DFQ) using mesoporous silica nanoparticles modified with tungstophosphoric acid as a catalyst.

2019-01-01T00:00:00Z Los heterociclos están presentes en la mayoría de productos naturales bioactivos y drogas sintéticas, entre otras. Las aminas heterocíclicas son sustancias, muy comunes y tienen muchas propiedades biológicas importantes. Entre estas aminas, encontramos a las quinoxalinas, estas sustancias son de gran interés químico y biológico debido a la versatilidad que poseen, ya que pueden usarse en colorantes, agroquímicos y como bloques de construcción en fármacos, siendo este último uso uno de los más importantes en la química medicinal. Desde su descubrimiento, la síntesis de estos compuestos fue creciendo en interés en la medida que se descubrían sus propiedades, siendo la actividad bilógica una de las más importantes. Motivados con estos antecedentes y la creciente demanda medioambiental de generar nuevas rutas de síntesis que involucren la catálisis heterogénea como punto de partida, en el presente trabajo se reporta la síntesis de 2,3 difenilquinoxalina (DFQ) empleando nanoparticulas de sílice mesoporosa modificadas con ácido tungstofosfórico como catalizador. Heterocycles are present in most bioactive natural products and synthetic drugs, among others. Heterocyclic amines are substances, very common and have many important biological properties. Among these amines, we find quinoxalines, these substances are of great chemical and biological interest due to the versatility they possess, since they can be used in dyes, agrochemicals and as building blocks in drugs, the latter being one of the most important in medicinal chemistry. Since its discovery, the synthesis of these compounds was growing in interest as their properties were discovered, being the biological activity one of the most important. Motivated by this background and the growing environmental demand to generate new synthetic routes that involve heterogeneous catalysis as a starting point, in this work we report the synthesis of 2,3 diphenylquinoxaline (DFQ) using mesoporous silica nanoparticles modified with tungstophosphoric acid as a catalyst. Portilla Zúñiga, Omar Miguel Romanelli, Gustavo Pablo Sathicq, Ángel Gabriel http://sedici.unlp.edu.ar:80/handle/10915/197147 2026-08-04T20:23:37Z 2019-01-01T00:00:00Z

Articulo Anales de la Asociación Química Argentina; vol. 106, no. 1 Las dihidropirimidinonas (DHPMS) son compuestos orgánicos que han mostrado ser biológicamente activos. Por tal razón es importante el estudio de su preparación por metodologías más eficientes. En este trabajo se desarrolló un método eficiente, práctico y con alto rendimiento para la síntesis de DHPMS siguiendo una metodología libre de disolvente mediante el uso como catalizador del ácido de Preyssler (H₁₄NaP₅W₂₉MoO₁₁₀) encapsulado en una red de sílice. Las DHPMS se obtienen siguiendo la metodología de Biginelli, usando como material de partida furfural y 5-metilfurfural dos derivados de biomasa. El catalizador estudiado es reutilizable, limpio e insoluble en solventes orgánicos. El proceso cuenta con una alta economía atómica y un corto tiempo de reacción en comparación a los procesos desarrollados con otros heteropoliácidos. Todos los productos obtenidos fueron caracterizados mediante técnicas espectroscópicas clásicas.; Dihydropyrimidinones are organic compounds with biological activity. For this reason, it is important to study their preparation for efficient methodologies. In this work we developed an efficient, practical and high performance method for the synthesis of DHPMS following a solvent-free methodology using Preyssler acid (H₁₄NaP₅W₂₉MoO₁₁₀) encapsulated in a silica framework as catalyst. The DHPMS are obtained following the Biginelli methodology, using two biomass derivatives as starting material (furfural and 5-methylfurfural). The catalyst studied is reusable, clean and insoluble in organic solvents. The process has a high atomic economy and a short reaction time compared to the processes developed with other heteropolyacids. All the products obtained were characterized by classical spectroscopic techniques.

2019-01-01T00:00:00Z Las dihidropirimidinonas (DHPMS) son compuestos orgánicos que han mostrado ser biológicamente activos. Por tal razón es importante el estudio de su preparación por metodologías más eficientes. En este trabajo se desarrolló un método eficiente, práctico y con alto rendimiento para la síntesis de DHPMS siguiendo una metodología libre de disolvente mediante el uso como catalizador del ácido de Preyssler (H₁₄NaP₅W₂₉MoO₁₁₀) encapsulado en una red de sílice. Las DHPMS se obtienen siguiendo la metodología de Biginelli, usando como material de partida furfural y 5-metilfurfural dos derivados de biomasa. El catalizador estudiado es reutilizable, limpio e insoluble en solventes orgánicos. El proceso cuenta con una alta economía atómica y un corto tiempo de reacción en comparación a los procesos desarrollados con otros heteropoliácidos. Todos los productos obtenidos fueron caracterizados mediante técnicas espectroscópicas clásicas. Dihydropyrimidinones are organic compounds with biological activity. For this reason, it is important to study their preparation for efficient methodologies. In this work we developed an efficient, practical and high performance method for the synthesis of DHPMS following a solvent-free methodology using Preyssler acid (H₁₄NaP₅W₂₉MoO₁₁₀) encapsulated in a silica framework as catalyst. The DHPMS are obtained following the Biginelli methodology, using two biomass derivatives as starting material (furfural and 5-methylfurfural). The catalyst studied is reusable, clean and insoluble in organic solvents. The process has a high atomic economy and a short reaction time compared to the processes developed with other heteropolyacids. All the products obtained were characterized by classical spectroscopic techniques. Navas, Marisa Belén Ruggera, José Fernando Casella, Mónica Laura http://sedici.unlp.edu.ar:80/handle/10915/197145 2026-08-04T20:23:37Z 2019-01-01T00:00:00Z

Articulo Anales de la Asociación Química Argentina; vol. 06, no. 1 Con el fin de estudiar la reacción de transesterificación de aceite de soja empleando metanol, se prepararon catalizadores de CaO, MgO y ZnO soportados en γ-Al₂O₃, y mezclas en relaciones molares 0.25, 0.5, 1 y 5 entre Mg/Ca y Zn/Ca. Los catalizadores fueron caracterizados empleando difracción de rayos X, fisisorción de N₂ y microscopía de barrido electrónico. Los catalizadores preparados presentaron en todos los casos características de sólidos mesoporosos, de gran área superficial, exhibiendo la fase cristalina óxido. Los catalizadores mezcla de MgO y CaO exhibieron selectividades a ésteres metílicos de ácidos grasos (FAME) muy cercanas al 100%, aunque ninguno superó en rendimiento a FAME al catalizador puro de MgO, que presentó un máximo de 57%. Los catalizadores mezcla de ZnO y CaO de proporciones 0.25, 0.5 y 1 Zn/Ca presentaron selectividades a FAME muy cercanas al 100%, y un rendimiento a FAME máximo de 37% para el catalizador 1 Zn/Ca.; In order to study the transesterification reaction of soybean oil with methanol, γ-Al₂O₃-supported CaO, MgO and ZnO catalysts were prepared, as well as mixtures of Mg/Ca and Zn/Ca having molar ratios of 0.25, 0.5, 1 and 5. The catalysts were characterized using X-ray diffraction (XRD), N₂ physisorption and electron scanning microscopy (SEM). The results were consistent in all the cases with mesoporous solids, with large surface areas, exhibiting the oxide crystalline phase. Mg/Ca mixed catalysts presented fatty acids methyl esters (FAME) selectivities of almost 100%. Nevertheless, no mixture exceeded the FAME yield of the pure MgO catalyst, which showed a maximum of 57%. Zn/Ca mixed catalysts of 0.25, 0.5 and 1 atomic ratios, showed FAME selectivities very close to 100%. A maximum FAME yield of 37% was obtained with the Zn/Ca catalyst having an atomic ratio of 1.

2019-01-01T00:00:00Z Con el fin de estudiar la reacción de transesterificación de aceite de soja empleando metanol, se prepararon catalizadores de CaO, MgO y ZnO soportados en γ-Al₂O₃, y mezclas en relaciones molares 0.25, 0.5, 1 y 5 entre Mg/Ca y Zn/Ca. Los catalizadores fueron caracterizados empleando difracción de rayos X, fisisorción de N₂ y microscopía de barrido electrónico. Los catalizadores preparados presentaron en todos los casos características de sólidos mesoporosos, de gran área superficial, exhibiendo la fase cristalina óxido. Los catalizadores mezcla de MgO y CaO exhibieron selectividades a ésteres metílicos de ácidos grasos (FAME) muy cercanas al 100%, aunque ninguno superó en rendimiento a FAME al catalizador puro de MgO, que presentó un máximo de 57%. Los catalizadores mezcla de ZnO y CaO de proporciones 0.25, 0.5 y 1 Zn/Ca presentaron selectividades a FAME muy cercanas al 100%, y un rendimiento a FAME máximo de 37% para el catalizador 1 Zn/Ca. In order to study the transesterification reaction of soybean oil with methanol, γ-Al₂O₃-supported CaO, MgO and ZnO catalysts were prepared, as well as mixtures of Mg/Ca and Zn/Ca having molar ratios of 0.25, 0.5, 1 and 5. The catalysts were characterized using X-ray diffraction (XRD), N₂ physisorption and electron scanning microscopy (SEM). The results were consistent in all the cases with mesoporous solids, with large surface areas, exhibiting the oxide crystalline phase. Mg/Ca mixed catalysts presented fatty acids methyl esters (FAME) selectivities of almost 100%. Nevertheless, no mixture exceeded the FAME yield of the pure MgO catalyst, which showed a maximum of 57%. Zn/Ca mixed catalysts of 0.25, 0.5 and 1 atomic ratios, showed FAME selectivities very close to 100%. A maximum FAME yield of 37% was obtained with the Zn/Ca catalyst having an atomic ratio of 1. Morales, María Dolores Romanelli, Gustavo Pablo Pizzio, Luis René http://sedici.unlp.edu.ar:80/handle/10915/197143 2026-08-04T20:23:38Z 2019-01-01T00:00:00Z

Articulo Anales de la Asociación Química Argentina; vol. 106, no. 1 Se sintetizó sílice mesoporosa con estructura ordenada empleando Pluronic P123 como formador de poro, tetraetilortosilicato (TEOS) como alcóxido precursor y un volumen variable de solución de agar al 0,5 % p/p. Los materiales se caracterizaron mediante BET, FT-IR, titulación potenciométrica con n-butilamina, DRX y SAXS, exhibiendo excelentes propiedades texturales para su empleo como soporte de heteropoliácidos. La caracterización de los materiales resultantes de la inmovilización del ácido tungstofosfórico (H₃PW₁₂O₄₀, TPA) en el soporte, mostró que la estructura Keggin de dicho ácido se encuentra presente en el material sintetizado y que los mismos presentan una alta acidez. Por este motivo, resultan potencialmente adecuados para su aplicación en reacciones de síntesis orgánica de tipo one-pot.; Mesoporous silica with an ordered structure was synthesized, using Pluronic P123 as a template, tetraethylorthosilicate (TEOS) as alkoxide precursor and a variable volume of 0.5% p/p aqueous agar solution. The materials were characterized by BET, FT-IR, potentiometric titration with nbutylamine, XRD and SAXS. They showed excellent textural properties for their use as heteropolyacid support. The characterization of the materials obtained from the immobilization of tungstophosphoric acid (H₃PW₁₂O₄₀) showed that the Keggin structure is present in the synthesized material and that they have a high acidity. Thus, the prepared catalysts are potentially suitable for their application in one-pot organic synthesis reactions.

2019-01-01T00:00:00Z Se sintetizó sílice mesoporosa con estructura ordenada empleando Pluronic P123 como formador de poro, tetraetilortosilicato (TEOS) como alcóxido precursor y un volumen variable de solución de agar al 0,5 % p/p. Los materiales se caracterizaron mediante BET, FT-IR, titulación potenciométrica con n-butilamina, DRX y SAXS, exhibiendo excelentes propiedades texturales para su empleo como soporte de heteropoliácidos. La caracterización de los materiales resultantes de la inmovilización del ácido tungstofosfórico (H₃PW₁₂O₄₀, TPA) en el soporte, mostró que la estructura Keggin de dicho ácido se encuentra presente en el material sintetizado y que los mismos presentan una alta acidez. Por este motivo, resultan potencialmente adecuados para su aplicación en reacciones de síntesis orgánica de tipo one-pot. Mesoporous silica with an ordered structure was synthesized, using Pluronic P123 as a template, tetraethylorthosilicate (TEOS) as alkoxide precursor and a variable volume of 0.5% p/p aqueous agar solution. The materials were characterized by BET, FT-IR, potentiometric titration with nbutylamine, XRD and SAXS. They showed excellent textural properties for their use as heteropolyacid support. The characterization of the materials obtained from the immobilization of tungstophosphoric acid (H₃PW₁₂O₄₀) showed that the Keggin structure is present in the synthesized material and that they have a high acidity. Thus, the prepared catalysts are potentially suitable for their application in one-pot organic synthesis reactions. Méndez, Leticia Jesica Lick, Ileana Daniela Cánepa, Alicia Susana http://sedici.unlp.edu.ar:80/handle/10915/197141 2026-08-04T20:23:35Z 2019-01-01T00:00:00Z

Articulo Anales de la Asociación Química Argentina; vol. 106, no. 1 Se estudió la reacción de acilación de 3-metilindol para la obtención de derivados 2-acetil y N-acetil índoles, usando catalizadores homogéneos del tipo líquido iónico (TEBSA, TMBSA y Nafion sc.) y un catalizador heterogéneo como SAC 13. Los catalizadores algunos fueron obtenidos por síntesis en el Laboratorio y otros se adquirieron comercialmente. Los productos fueron obtenidos con una selectividad del 71% hacia uno de los isómeros en tiempos de reacción de 1 hora con la conversión completa del reactivo. Los mismos fueron caracterizados mediante espectroscopia de ¹H RMN y ¹³C RMN. Pudo obtenerse de manera selectiva el N-acetil-3-metilindol y el 2-acetil-3-metilindol bajo ciertas condiciones de reacción usando un método eco-compatible.; The acylation reaction of 3-methylindole to obtain 2-acetyl and N-acetyl derivatives was studied using ionic liquids (TEBSA, TMBSA and Nafion sc.) as homogeneous catalysts and a heterogeneous catalyst such as SAC 13. Some of the catalysts used were of synthetic origin and others were purchased commercially. The products were obtained with 71% selectivity towards one of the isomers, with reaction times of 1 hour and complete conversión of the reagent. They were characterized by ¹H-NMR and ¹³C-NMR spectroscopy. N-acetyl-3-methylindole and 2-acetyl-3- methylindole could be obtained selectively under certain reaction conditions using an eco-compatible method.

2019-01-01T00:00:00Z Se estudió la reacción de acilación de 3-metilindol para la obtención de derivados 2-acetil y N-acetil índoles, usando catalizadores homogéneos del tipo líquido iónico (TEBSA, TMBSA y Nafion sc.) y un catalizador heterogéneo como SAC 13. Los catalizadores algunos fueron obtenidos por síntesis en el Laboratorio y otros se adquirieron comercialmente. Los productos fueron obtenidos con una selectividad del 71% hacia uno de los isómeros en tiempos de reacción de 1 hora con la conversión completa del reactivo. Los mismos fueron caracterizados mediante espectroscopia de ¹H RMN y ¹³C RMN. Pudo obtenerse de manera selectiva el N-acetil-3-metilindol y el 2-acetil-3-metilindol bajo ciertas condiciones de reacción usando un método eco-compatible. The acylation reaction of 3-methylindole to obtain 2-acetyl and N-acetyl derivatives was studied using ionic liquids (TEBSA, TMBSA and Nafion sc.) as homogeneous catalysts and a heterogeneous catalyst such as SAC 13. Some of the catalysts used were of synthetic origin and others were purchased commercially. The products were obtained with 71% selectivity towards one of the isomers, with reaction times of 1 hour and complete conversión of the reagent. They were characterized by ¹H-NMR and ¹³C-NMR spectroscopy. N-acetyl-3-methylindole and 2-acetyl-3- methylindole could be obtained selectively under certain reaction conditions using an eco-compatible method. Matkovic, Silvana Raquel Bosco, Marta Collins, Sebastián E. Briand, Laura Estefanía http://sedici.unlp.edu.ar:80/handle/10915/197140 2026-08-04T20:23:38Z 2019-01-01T00:00:00Z

Articulo Anales de la Asociación Química Argentina; vol. 106, no, 1 El objetivo de esta investigación fue estudiar la interacción de la piridina con el ácido fosfotúngstico de Wells Dawson H₆P₂W₁₈O₆₂.13H₂O másico con el fin de determinar la naturaleza y número de sitios ácidos Brönsted y Lewis presentes en el mismo. Este estudio se realizó mediante la técnica de quimisorción de piridina a temperatura ambiente y análisis por espectroscopia infrarroja in situ de la evolución de la interacción entre la molécula sonda y el material. La evidencia experimental permitió concluir que la compresión del heteropoliácido fosfotúngtico durante la preparación de una pastilla auto-soportada como también la baja superficie específica del material inhiben la adsorción de la molécula sonda.; This contribution investigates the interaction between pyridine and bulk phosphotungstic Wells Dawson heteropolyacid H₆P₂W₁₈O₆₂.13H₂O in order to determine the nature and number of both Lewis and Brønsted acid sites. This study was performed through the chemisorption of pyridine at R.T. followed by the continuous analysis of the material with in situ infrared spectroscopy. The results allowed to conclude that the compression of the material during the preparation of the self-supported wafer and the low surface area of the heteropolyacid inhibit the adsorption of the molecular probe.

2019-01-01T00:00:00Z El objetivo de esta investigación fue estudiar la interacción de la piridina con el ácido fosfotúngstico de Wells Dawson H₆P₂W₁₈O₆₂.13H₂O másico con el fin de determinar la naturaleza y número de sitios ácidos Brönsted y Lewis presentes en el mismo. Este estudio se realizó mediante la técnica de quimisorción de piridina a temperatura ambiente y análisis por espectroscopia infrarroja in situ de la evolución de la interacción entre la molécula sonda y el material. La evidencia experimental permitió concluir que la compresión del heteropoliácido fosfotúngtico durante la preparación de una pastilla auto-soportada como también la baja superficie específica del material inhiben la adsorción de la molécula sonda. This contribution investigates the interaction between pyridine and bulk phosphotungstic Wells Dawson heteropolyacid H₆P₂W₁₈O₆₂.13H₂O in order to determine the nature and number of both Lewis and Brønsted acid sites. This study was performed through the chemisorption of pyridine at R.T. followed by the continuous analysis of the material with in situ infrared spectroscopy. The results allowed to conclude that the compression of the material during the preparation of the self-supported wafer and the low surface area of the heteropolyacid inhibit the adsorption of the molecular probe. Llerena Suster, Carlos Rafael Díaz Merino, Matías Ezequiel Morcelle del Valle, Susana Raquel Briand, Laura Estefanía http://sedici.unlp.edu.ar:80/handle/10915/197139 2026-08-04T20:23:18Z 2019-01-01T00:00:00Z

Articulo Anales de la Asociación Química Argentina; vol. 106, no. 1 En el presente trabajo se prepararon biocatalizadores por adsorción simple de la lipasa B de Candida antarctica (CALB) sobre dióxido de silicio nanoestructurado que se aplicaron en la resolución cinética enzimática de ibuprofeno racémico. Se estudió la cinética de inmovilización y la isoterma de adsorción de la lipasa a partir de distintas soluciones de un extracto crudo. El límite máximo de dispersión de la proteína sobre el óxido es de 0,025µmoles/m² (25mg cada 100mg de soporte) y se obtuvo en menos de 30 minutos de inmovilización. Mediante electroforesis desnaturalizante, se determinó que existió una adsorción selectiva de la CALB con respecto a otras proteínas del extracto enzimático. Los biocatalizadores se utilizaron para esterificar ibuprofeno con etanol en isooctano como cosolvente. Se alcanzó un 70% de conversión a las 24 hs. con 58% de exceso enantiomérico hacia el Sibuprofeno. Los ensayos de estabilidad mostraron que los biocatalizadores sólo perdieron entre 7 y 25% de su actividad después de más de siete meses de almacenamiento a 4 °C. Los biocatalizadores con mayor carga enzimática resultaron ser los más estables.; This investigation presents the synthesis of biocatalysts based on the lipase B of Candida antarctica CALB adsorbed on nanostructured silica oxide and their application of the kinetic resolution of racemic ibuprofen. The kinetic of the immobilization and the isotherm of adsorption were studied. The maximum dispersion limit of the protein onto the oxide support was 0,025µmoles/m² (25mg per 100mg of support) and was achieved in 30min of immobilization. The studies by SDS-PAGE indicated that CALB was selectively adsorbed onto the SiO₂ support. The biocatalysts were used in the esterification of ibuprofen with ethanol with isooctane as cosolvent. The conversion of ibuprofen reached up to 70% at 24 hours of reaction with 58% of enantiomeric excess towards de S-ibuprofen. The stability assays showed that the biocatalysts only lost between 7 and 25% of their activity after more than seven months of storage at 4ºC. Those biocatalysts with a protein loading higher than 21 mg onto 100mg of support were the most stable ones.

2019-01-01T00:00:00Z En el presente trabajo se prepararon biocatalizadores por adsorción simple de la lipasa B de Candida antarctica (CALB) sobre dióxido de silicio nanoestructurado que se aplicaron en la resolución cinética enzimática de ibuprofeno racémico. Se estudió la cinética de inmovilización y la isoterma de adsorción de la lipasa a partir de distintas soluciones de un extracto crudo. El límite máximo de dispersión de la proteína sobre el óxido es de 0,025µmoles/m² (25mg cada 100mg de soporte) y se obtuvo en menos de 30 minutos de inmovilización. Mediante electroforesis desnaturalizante, se determinó que existió una adsorción selectiva de la CALB con respecto a otras proteínas del extracto enzimático. Los biocatalizadores se utilizaron para esterificar ibuprofeno con etanol en isooctano como cosolvente. Se alcanzó un 70% de conversión a las 24 hs. con 58% de exceso enantiomérico hacia el Sibuprofeno. Los ensayos de estabilidad mostraron que los biocatalizadores sólo perdieron entre 7 y 25% de su actividad después de más de siete meses de almacenamiento a 4 °C. Los biocatalizadores con mayor carga enzimática resultaron ser los más estables. This investigation presents the synthesis of biocatalysts based on the lipase B of Candida antarctica CALB adsorbed on nanostructured silica oxide and their application of the kinetic resolution of racemic ibuprofen. The kinetic of the immobilization and the isotherm of adsorption were studied. The maximum dispersion limit of the protein onto the oxide support was 0,025µmoles/m² (25mg per 100mg of support) and was achieved in 30min of immobilization. The studies by SDS-PAGE indicated that CALB was selectively adsorbed onto the SiO₂ support. The biocatalysts were used in the esterification of ibuprofen with ethanol with isooctane as cosolvent. The conversion of ibuprofen reached up to 70% at 24 hours of reaction with 58% of enantiomeric excess towards de S-ibuprofen. The stability assays showed that the biocatalysts only lost between 7 and 25% of their activity after more than seven months of storage at 4ºC. Those biocatalysts with a protein loading higher than 21 mg onto 100mg of support were the most stable ones. Leguizamón Aparicio, María Silvia del Valle Montaña, Maia Ruiz, María L. Mosconi, Sandra M. Musci, Juan José Ocsachoque, Marco Antonio Casella, Mónica Laura Lick, Ileana Daniela http://sedici.unlp.edu.ar:80/handle/10915/197138 2026-08-04T20:23:38Z 2019-01-01T00:00:00Z

Articulo Anales de la Asociación Química Argentina; vol. 106, no, 1 In this work, cordierite-supported potassium nitrate catalysts modified with transition metal oxides are studied as catalysts for the particulate matter combustion from diesel engine emissions. The catalysts were prepared by nitrate solutions. The catalysts were characterized by XRD, differential scanning calorimetry (DSC), thermal programmed reduction (TPR), vibrational spectroscopy (FTIR) and Scanning microscopy provided with EDS analyzer. KNO₃ containing catalysts present high activity in the presence of O₂/NO. The Tmax obtained with these catalysts decreases more than 200 ºC with respect to the temperature of the non-catalyzed process. The activity is associated with the presence of KNO₃ and the role of this salt can be attributed to the NO³⁻/NO²⁻ redox cycle contribution and to the surface wetting effect.; En este trabajo se estudian catalizadores de nitrato de potasio modificados con óxidos de metales de transición soportados sobre cordierita como catalizadores para la combustión de material particulado proveniente de emisiones de motores Diesel. Los catalizadores se prepararon mediante el método de humedad incipiente utilizando los respectivos nitratos. Estos catalizadores se caracterizaron mediante difracción de rayos X (DRX), calorimetría diferencial de barrido (DSC), reducción a temperatura programada (TPR), espectroscopía FTIR y microscopía de barrido provista con analizador EDS. Los catalizadores que contienen KNO₃ presentan alta actividad en presencia de O₂/NO. La temperatura de la máxima velocidad de quemado disminuye más de 200 ºC con respecto al proceso sin catalizador. La actividad se puede asociar con la presencia del KNO₃ y la contribución del par redox NO³⁻/NO²⁻ y al efecto de mojado de la superficie que aporta la sal soportada.

2019-01-01T00:00:00Z In this work, cordierite-supported potassium nitrate catalysts modified with transition metal oxides are studied as catalysts for the particulate matter combustion from diesel engine emissions. The catalysts were prepared by nitrate solutions. The catalysts were characterized by XRD, differential scanning calorimetry (DSC), thermal programmed reduction (TPR), vibrational spectroscopy (FTIR) and Scanning microscopy provided with EDS analyzer. KNO₃ containing catalysts present high activity in the presence of O₂/NO. The Tmax obtained with these catalysts decreases more than 200 ºC with respect to the temperature of the non-catalyzed process. The activity is associated with the presence of KNO₃ and the role of this salt can be attributed to the NO³⁻/NO²⁻ redox cycle contribution and to the surface wetting effect. En este trabajo se estudian catalizadores de nitrato de potasio modificados con óxidos de metales de transición soportados sobre cordierita como catalizadores para la combustión de material particulado proveniente de emisiones de motores Diesel. Los catalizadores se prepararon mediante el método de humedad incipiente utilizando los respectivos nitratos. Estos catalizadores se caracterizaron mediante difracción de rayos X (DRX), calorimetría diferencial de barrido (DSC), reducción a temperatura programada (TPR), espectroscopía FTIR y microscopía de barrido provista con analizador EDS. Los catalizadores que contienen KNO₃ presentan alta actividad en presencia de O₂/NO. La temperatura de la máxima velocidad de quemado disminuye más de 200 ºC con respecto al proceso sin catalizador. La actividad se puede asociar con la presencia del KNO₃ y la contribución del par redox NO³⁻/NO²⁻ y al efecto de mojado de la superficie que aporta la sal soportada. García Beltrán, Karla Paola Rodríguez Muñiz, Gemma M. Lhiaubet-Vallet, Virginie Thomas, Andrés Héctor Dántola, María Laura http://sedici.unlp.edu.ar:80/handle/10915/197123 2026-08-03T20:24:28Z 2026-01-01T00:00:00Z

Articulo Redox Biochemistry and Chemistry; vol. 15 3,3′-Dityrosine, resulting from the formation of a carbon-carbon bond between two tyrosines (Tyr), is one of the most important modifications of the oxidatively generated damage to proteins. Its formation can induce structural changes in proteins, leading to the loss of their biological function. Interestingly, under UVA radiation, dityrosine can also act as an intrinsic photosensitizer that generates reactive oxygen species and induces chemical modifications in amino acids. Despite the biomedical importance of dityrosine, the information regarding its photosensitized generation and photochemical properties is limited due to the drawbacks inherent to its synthesis. In this work we studied the photosensitized formation of dityrosine, in the absence and presence of tryptophan (Trp), using pterin (Ptr) as endogenous type I sensitizer. Free Tyr and Tyr incorporated into specially designed peptides were used as target molecules. Our results indicate that the efficiency of dimerization is not affected by the presence of the peptide bond. Nonetheless, incorporation of dityrosine into a peptide chain appears to confer a certain degree of protection, making it more resistant to photosensitized degradation. Moreover, we demonstrated that, within a peptide chain, an adjacent Trp residue promotes the photoinduced dimerization of Tyr, likely due to electron transfer from the Tyr residue to the oxidized Trp. This effect is not observed when the two residues are more distant. Additionally, the presence of free Trp or Trp within the same peptide chain enhances the efficiency of the photosensitized degradation of the free and peptide dityrosine, respectively.

2026-01-01T00:00:00Z 3,3′-Dityrosine, resulting from the formation of a carbon-carbon bond between two tyrosines (Tyr), is one of the most important modifications of the oxidatively generated damage to proteins. Its formation can induce structural changes in proteins, leading to the loss of their biological function. Interestingly, under UVA radiation, dityrosine can also act as an intrinsic photosensitizer that generates reactive oxygen species and induces chemical modifications in amino acids. Despite the biomedical importance of dityrosine, the information regarding its photosensitized generation and photochemical properties is limited due to the drawbacks inherent to its synthesis. In this work we studied the photosensitized formation of dityrosine, in the absence and presence of tryptophan (Trp), using pterin (Ptr) as endogenous type I sensitizer. Free Tyr and Tyr incorporated into specially designed peptides were used as target molecules. Our results indicate that the efficiency of dimerization is not affected by the presence of the peptide bond. Nonetheless, incorporation of dityrosine into a peptide chain appears to confer a certain degree of protection, making it more resistant to photosensitized degradation. Moreover, we demonstrated that, within a peptide chain, an adjacent Trp residue promotes the photoinduced dimerization of Tyr, likely due to electron transfer from the Tyr residue to the oxidized Trp. This effect is not observed when the two residues are more distant. Additionally, the presence of free Trp or Trp within the same peptide chain enhances the efficiency of the photosensitized degradation of the free and peptide dityrosine, respectively. Teijeiro, Manuel De Antoni, Graciela Liliana Golowczyc, Marina Alejandra Pérez, Pablo Fernando http://sedici.unlp.edu.ar:80/handle/10915/197122 2026-08-03T20:24:15Z 2026-01-01T00:00:00Z

Articulo Impacto de Lactiplantibacillus plantarum CIDCA 83114 secado por spray en un modelo murino de giardiasis Revista Argentina de Microbiología; vol. 58, no. 3 This study investigates the efficacy of spray-dried Lactiplantibacillus plantarum CIDCA 83114 in a murine model of giardiasis. Mice (C57BL/6) were divided into four groups: control, Giardia-only, probiotic-only, and a combined (probiotic + Giardia, PG) group. Probiotic treatment started one week pre-infection with Giardia intestinalis H7 and continued throughout the study. Infection was monitored through trophozoite counts, intestinal histology, cytokine expression and microbiome analysis. Histology revealed that the administration of strain CIDCA 83114 prior to infection, increases villus/crypt ratios compared with control infected animals. In addition, trophozoite counts in the small intestine were lower in probiotic-treated mice than in infected control animals. Probiotic-treated infected mice showed significantly higher IL-10 expression than untreated controls. Expression of the IL-12 gene was diminished in animals administered with strain CIDCA 83114 (both infected and non-infected with Giardia). In addition, Giardia infection led to a decrease in IFN-g expression, even when the probiotic-treated animals. Expression of TNF-a increased in the groups treated only with strain CIDCA 83114 and in infected animals. Notably, the PG group exhibited lower values of TNF-a expression, potentially due to the elevated IL-10 levels detected in this group. Dysbiosis associated with Giardia infection led to an increase in Epsilonproteobacteria and Clostridium. These changes were abrogated in the group that received the probiotic strain, which, as expected, showed an increase in Lactobacillaceae. This study demonstrates that spray-dried probiotic L. plantarum CIDCA 83114 has a positive impact on key aspects of Giardia infection, supporting its potential as a preventive or therapeutic strategy for giardiasis.

2026-01-01T00:00:00Z This study investigates the efficacy of spray-dried Lactiplantibacillus plantarum CIDCA 83114 in a murine model of giardiasis. Mice (C57BL/6) were divided into four groups: control, Giardia-only, probiotic-only, and a combined (probiotic + Giardia, PG) group. Probiotic treatment started one week pre-infection with Giardia intestinalis H7 and continued throughout the study. Infection was monitored through trophozoite counts, intestinal histology, cytokine expression and microbiome analysis. Histology revealed that the administration of strain CIDCA 83114 prior to infection, increases villus/crypt ratios compared with control infected animals. In addition, trophozoite counts in the small intestine were lower in probiotic-treated mice than in infected control animals. Probiotic-treated infected mice showed significantly higher IL-10 expression than untreated controls. Expression of the IL-12 gene was diminished in animals administered with strain CIDCA 83114 (both infected and non-infected with Giardia). In addition, Giardia infection led to a decrease in IFN-g expression, even when the probiotic-treated animals. Expression of TNF-a increased in the groups treated only with strain CIDCA 83114 and in infected animals. Notably, the PG group exhibited lower values of TNF-a expression, potentially due to the elevated IL-10 levels detected in this group. Dysbiosis associated with Giardia infection led to an increase in Epsilonproteobacteria and Clostridium. These changes were abrogated in the group that received the probiotic strain, which, as expected, showed an increase in Lactobacillaceae. This study demonstrates that spray-dried probiotic L. plantarum CIDCA 83114 has a positive impact on key aspects of Giardia infection, supporting its potential as a preventive or therapeutic strategy for giardiasis. Vaquero, Ana Calderon Ruiz, Paula Gambaro, Rocío Celeste Rivero Berti, Ignacio Limeres, María José Ghazi, Silvia Fraude El Huck-Iriart, Cristián Meyer, Claudius U. Cacicedo, Maximiliano Luis Hankeln, Thomas Si, Shutian Lieberwirth, Ingo Landfester, Katharina Soto, Catalina Alba Tekiel, Valeria Bros, Matthias Gehring, Stephan Islan, Germán Abel http://sedici.unlp.edu.ar:80/handle/10915/197050 2026-07-17T20:25:33Z 2025-01-01T00:00:00Z

Articulo International Journal of Biological Macromolecules Volume:; vol. 330, parte 1 Lipid nanoparticles (LNPs) were engineered for efficient mRNA delivery and immune enhancement through co- encapsulation of adjuvants. CpG-oligodeoxynucleotides (CpG-ODN, TLR9 agonist) and monophosphoryl lipid A (MPLA, TLR4 agonist) were incorporated to activate intra- and extracellular Toll-like receptor pathways. Formulated via microfluidics, CpG was added in the aqueous phase and MPLA in the lipid phase. The final LNP- MPLA-CpG formulation included Luc mRNA and CpG-ODN (5:1 ratio) with ALC-0315/DSPC/cholesterol/ALC- 0159/MPLA (1 %). Particle characterization by DLS and NTA confirmed neutral, homogeneous nanoparticles (~80 nm). Cryo-TEM and SAXS verified structural integrity. The formulation maintained over 80 % mRNA encapsulation after storage at 4 ◦ C and − 80 ◦ C. Transfection of human and murine dendritic cells (MoDCs and DC2.4) led to robust protein expression. The LNPs showed minimal hemotoxicity and low cytotoxicity, while significantly increasing pro-inflammatory cytokines (IFN-γ, TNF-α, IL-6) in both cell types. DC uptake of LNP- MPLA-CpG was efficient. In the in vivo biodistribution, Luc mRNA was primarily expressed in liver and spleen following intramuscular injection. Serum cytokine levels peaked at 6 h post-injection, and flow cytometry of stimulated splenocytes and liver non-parenchymal cells confirmed a strong innate activation. These results support LNP co-delivery of dual adjuvants as a potent platform for enhancing mRNA vaccine efficacy and innate immune activation.

2025-01-01T00:00:00Z Lipid nanoparticles (LNPs) were engineered for efficient mRNA delivery and immune enhancement through co- encapsulation of adjuvants. CpG-oligodeoxynucleotides (CpG-ODN, TLR9 agonist) and monophosphoryl lipid A (MPLA, TLR4 agonist) were incorporated to activate intra- and extracellular Toll-like receptor pathways. Formulated via microfluidics, CpG was added in the aqueous phase and MPLA in the lipid phase. The final LNP- MPLA-CpG formulation included Luc mRNA and CpG-ODN (5:1 ratio) with ALC-0315/DSPC/cholesterol/ALC- 0159/MPLA (1 %). Particle characterization by DLS and NTA confirmed neutral, homogeneous nanoparticles (~80 nm). Cryo-TEM and SAXS verified structural integrity. The formulation maintained over 80 % mRNA encapsulation after storage at 4 ◦ C and − 80 ◦ C. Transfection of human and murine dendritic cells (MoDCs and DC2.4) led to robust protein expression. The LNPs showed minimal hemotoxicity and low cytotoxicity, while significantly increasing pro-inflammatory cytokines (IFN-γ, TNF-α, IL-6) in both cell types. DC uptake of LNP- MPLA-CpG was efficient. In the in vivo biodistribution, Luc mRNA was primarily expressed in liver and spleen following intramuscular injection. Serum cytokine levels peaked at 6 h post-injection, and flow cytometry of stimulated splenocytes and liver non-parenchymal cells confirmed a strong innate activation. These results support LNP co-delivery of dual adjuvants as a potent platform for enhancing mRNA vaccine efficacy and innate immune activation. Borges, Augusto Miranda-Rodrı́guez, Jerónimo R. Ceccarelli, Alberto Sebastián Ventura, Guilherme Sedzinski, Jakub López-Schier, Hernán Chara, Osvaldo http://sedici.unlp.edu.ar:80/handle/10915/197038 2026-07-17T20:25:44Z 2025-01-01T00:00:00Z

Articulo iScience; vol. 28, no. 11 During tissue development and regeneration, cells interpret and exert mechanical forces that are challenging to measure in vivo. Stress inference algorithms have thus emerged as powerful tools to estimate tissue stresses. Yet, effectively incorporating tissue dynamics into these algorithms remains elusive. Here, we introduce ForSys, a Python-based software that infers intercellular stresses and intracellular pressures from time- lapse microscopy. After validation, we applied ForSys to the migrating zebrafish lateral-line primordium, revealing increased stress during the cell rounding that precedes mitosis and accurately predicting the onset of epithelial rosettogenesis. We further used ForSys to study neuromast development and uncovered mechanical asymmetries linked to cell type-specific adhesion. The software performs both static and dynamic stress inference, supports command-line use, scripting, and a user-friendly graphical interface within Fiji, and accepts segmentation inputs from EPySeg and Cellpose. This versatility of ForSys enables the analysis of spatiotemporal patterns of mechanical forces during tissue morphogenesis in vivo.

2025-01-01T00:00:00Z During tissue development and regeneration, cells interpret and exert mechanical forces that are challenging to measure in vivo. Stress inference algorithms have thus emerged as powerful tools to estimate tissue stresses. Yet, effectively incorporating tissue dynamics into these algorithms remains elusive. Here, we introduce ForSys, a Python-based software that infers intercellular stresses and intracellular pressures from time- lapse microscopy. After validation, we applied ForSys to the migrating zebrafish lateral-line primordium, revealing increased stress during the cell rounding that precedes mitosis and accurately predicting the onset of epithelial rosettogenesis. We further used ForSys to study neuromast development and uncovered mechanical asymmetries linked to cell type-specific adhesion. The software performs both static and dynamic stress inference, supports command-line use, scripting, and a user-friendly graphical interface within Fiji, and accepts segmentation inputs from EPySeg and Cellpose. This versatility of ForSys enables the analysis of spatiotemporal patterns of mechanical forces during tissue morphogenesis in vivo. José, Carla Briand, Laura Estefanía http://sedici.unlp.edu.ar:80/handle/10915/197030 2026-07-17T20:25:23Z 2019-01-01T00:00:00Z

Articulo IV Jornadas en Ciencias Aplicadas "Dr. Jorge J. Ronco" (La Plata, 25 y 26 de septiembre de 2017); Anales de la Asociación Química Argentina; vol. 106, no. 1 La presente investigación evaluó la performance catalítica de la lipasa B de Candida antarctica inmovilizada en quitosano aplicada a la esterificación de rac-ibuprofeno con alcoholes de cadena corta, con y sin co-solvente agregado. Se evidencia que la adsorción de CALB sobre quitosano permite obtener un catalizador activo en la resolución cinética de rac-ibuprofeno, resultando actividades específicas iguales o levemente superiores a las obtenidas con el catalizador de referencia Novozym®4345. Las mejores performances catalíticas fueron obtenidas al emplear etanol como agente nucleofílico para ambos catalizadores. Respecto a la enantioselectividad, CALB adsorbida en quitosano resultó poco selectiva en las condiciones estudiadas, aumentando la discriminación de enantiómeros en presencia de acetonitrilo, condición en la cual el S-ibuprofeno es esterificado a mayor velocidad. Sin embargo, la actividad observada para este nuevo catalizador plantea la optimización de variables en la resolución cinética y su potencial aplicación en síntesis de prodrogas de rac-ibuprofeno.; The present investigation evaluated the catalytic performance of the lipase B of Candida antarctica immobilized in chitosan applied to the esterification of rac-ibuprofen with short chain alcohols, with and without added co-solvent. It is evident that the adsorption of CALB on chitosan allows to obtain an active catalyst in the kinetic resolution of rac-ibuprofen, resulting in specific activities equal or slightly higher than those obtained with the reference catalyst Novozym®4345. The best catalytic performances were obtained by using ethanol as a nucleophilic agent for both catalysts. Regarding the enantioselectivity, CALB adsorbed on chitosan was not selective in the conditions studied, increasing the discrimination of enantiomers in the presence of acetonitrile, a condition in which S-ibuprofen is esterified at a higher rate. However, the activity observed for this new catalyst raises the optimization of variables in the kinetic resolution and potential application in synthesis of rac-ibuprofen prodrugs.

2019-01-01T00:00:00Z La presente investigación evaluó la performance catalítica de la lipasa B de Candida antarctica inmovilizada en quitosano aplicada a la esterificación de rac-ibuprofeno con alcoholes de cadena corta, con y sin co-solvente agregado. Se evidencia que la adsorción de CALB sobre quitosano permite obtener un catalizador activo en la resolución cinética de rac-ibuprofeno, resultando actividades específicas iguales o levemente superiores a las obtenidas con el catalizador de referencia Novozym®4345. Las mejores performances catalíticas fueron obtenidas al emplear etanol como agente nucleofílico para ambos catalizadores. Respecto a la enantioselectividad, CALB adsorbida en quitosano resultó poco selectiva en las condiciones estudiadas, aumentando la discriminación de enantiómeros en presencia de acetonitrilo, condición en la cual el S-ibuprofeno es esterificado a mayor velocidad. Sin embargo, la actividad observada para este nuevo catalizador plantea la optimización de variables en la resolución cinética y su potencial aplicación en síntesis de prodrogas de rac-ibuprofeno. The present investigation evaluated the catalytic performance of the lipase B of Candida antarctica immobilized in chitosan applied to the esterification of rac-ibuprofen with short chain alcohols, with and without added co-solvent. It is evident that the adsorption of CALB on chitosan allows to obtain an active catalyst in the kinetic resolution of rac-ibuprofen, resulting in specific activities equal or slightly higher than those obtained with the reference catalyst Novozym®4345. The best catalytic performances were obtained by using ethanol as a nucleophilic agent for both catalysts. Regarding the enantioselectivity, CALB adsorbed on chitosan was not selective in the conditions studied, increasing the discrimination of enantiomers in the presence of acetonitrile, a condition in which S-ibuprofen is esterified at a higher rate. However, the activity observed for this new catalyst raises the optimization of variables in the kinetic resolution and potential application in synthesis of rac-ibuprofen prodrugs.