Desarrollo, Producción e Innovación en la Investigación científica
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Item Novel preparation of CMK-3 nanostructured material modified with titania applied in hydrogen uptake and storage.(Univesidsad Tecnológica Nacional., 2016) Juárez , Juliana María; Ledesma , Brenda Cecilia; Gómez Costa, Marcos Bruno; Beltramone, Andrea Raquel; Anunziata , Oscar Alfredo; Anunziata , Oscar Alfredo; Ledesma , Brenda CeciliaThis work deals with the development of a novel procedure to synthesize titania-modified nano structured carbon employing Ti-SBA-15 as hard template. The new mesoporous carbon displays high specific surface area of 1044 m2/g and large pore volume of 0.7 cm3/g. XRD pattern of Ti-CMK-3 indicates that the ordered structure of this material is similar to the CMK-3. XRD, XPS and UVeVis-DRS analysis indicated that Ti is highly dispersed as anatase phase in Ti-CMK-3. The synthesized Ti-CMK-3 exhibited significantly enhanced H2 storage properties (2.6 wt%, equivalent to 13 mmol/g) compared with CMK-3 without Ti (2.2 wt%, 11 mmol/g) at 77 K and 10 bar.Item Noble-bimetallic supported CMK-3 as a novel catalyst for hydrogenation of tetralin in the presence of sulfur and nitrogen.(Univesidsad Tecnológica Nacional., 2016) Vallés , Verónica Alejandra; Ledesma , Brenda Cecilia; Juárez , Juliana María; Gómez Costa, Marcos Bruno; Anunziata , Oscar Alfredo; Beltramone , Andrea Raquel; Anunziata , Oscar Alfredo; Juárez , Juliana María; Ledesma , Brenda CeciliaCarbon ordered mesoporous CMK-3 with high surface area and high pore volume promotes a very good dispersion of Pt or Ir monometallic and Pt-Ir-bimetallic crystallites in the carbon framework. High active and stable nanospecies are responsible for the good activity and selectivity found in the hydrogenation of tetralin to decalin in the presence of N as indole and S as dibenzothiophene under mild conditions in a Batch reactor. The catalysts prepared were extensively characterized by XRD, N2 adsorption isotherms, XPS, TEM, ICP, CO Chemisorption and TPR. The analysis showed that the carbon mesoporous structure was maintained after metal incorporation, and very high dispersed metal-supported catalyst was obtained. The activity was compared using the turnover number, Pt-Ir-CMK-3 being the most active cat alyst in the presence of the inhibitors. The bimetallic catalyst showed more resistance to inhibition than monometallic catalysts. The reusability of Pt-Ir-CMK-3 suggests that it is a potential catalyst for hydrotreating reactions.Item Vanadium and titanium oxide supported on mesoporous CMK-3 as new catalysts for oxidative desulfurization.(Univesidsad Tecnológica Nacional., 2017) Rivoira , Juliana María; Juárez , Juliana María; Falcón, Horacio; Gómez Costa, Marcos Bruno; Anunziata , Oscar Alfredo; Beltramone , Andrea Raquel; Anunziata , Oscar Alfredo; Juárez , Juliana MaríaDiesel emissions contribute to environmental issues associated to sulfur oxides released during the combustion process of fuels. Ultra-low-sulfur-diesel (ULSD) is diesel with substantially lowered sulfur content. Many countries have established regulations to restrict the S content in petroleum products to be 15 ppm and zero emission is even expected1 . Alternatively, oxidative desulfurization (ODS) provides selective removal of those refractory sulfur compounds at proper temperatures and pressure and is capable to eliminate most refractory sulfur compounds in HDS. This is the process wherein dibenzothiophene derivatives are converted to their corresponding sulfone, which could be easily separated from the oil. Therefore, ODS has a great potential to become a complementary process to traditional HDS in the production of deeply desulfurized diesel fuels. In view of the recent studies, Ti and V oxides have demonstrated to improve S-compounds oxidation2,3. In this work we evaluate vanadium and titanium-based catalysts supported over a mesoporous carbon with large surface area (CMK-3) in the ODS of dibenzothiophene as a model sulfur compound.Item Óxidos de vanadio y titanio soportados sobre CMK-3 como un nuevo catalizador para la desulfuración oxidativa de DBT.(Univesidsad Tecnológica Nacional., 2016) Rivoira , Lorena Paola; Juárez , Juliana María; Falcón, Horacio; Gómez Costa, Marcos Bruno; Anunziata , Oscar Alfredo; Beltramone, Andrea Raquel; Anunziata , Oscar Alfredo; Juárez , Juliana MaríaEn el presente trabajo se estudiaron catalizadores de vanadio soportados sobre el carbón mesoporosos CMK 3 con diferentes contenidos de Vanadio (1-7 % p/p) en la desulfurización oxidativa de dibenzotiofeno (DBT) como modelo de compuestos sulfurados. La actividad catalítica se comparó con catalizadores de Titanio soportados en CMK-3. Las propiedades estructurales y texturales de los catalizadores se analizaron mediante estudios de adsorción de N2, XRD, UV-Vis-DRS y TEM. Tanto la dispersión como la actividad catalítica dependen fuertemente del contenido de vanadio. La muestra que contiene el 7% p/p de Vanadio es el catalizador con mejor actividad catalítica para la reacción de ODS de DBT utilizando peróxido de hidrógeno ((H2O2) como oxidante y acetonitrilo como solvente. El 100% de la eliminación de DBT se alcanzó a corto plazo en condiciones suaves. El carbon mesoporoso CMK-3 con una alta área superficial y gran volumen de poros promueve el anclaje del metal en la red de carbono, lo que permite alcanzar una alta distribución de sitios activos y nanoclusters más estables. La reutilización del catalizador indica que V-CMK-3 es un catalizador potencial para los ODS de dibenzotiofeno.Item Synthesis and characterization of a nanoporous carbon CMK-3 modified with iron for the ODS of DBT.(Univesidsad Tecnológica Nacional., 2017) Juárez , Juliana María; Rivoira , Lorena Paola; Gómez Costa, Marcos Bruno; Anunziata , Oscar Alfredo; Beltramone , Andrea Raquel; Anunziata , Oscar Alfredo; Rivoira , Lorena PaolaA nanostructured Carbon CMK-3 modified with Fe by using different sources of Fe, were used in the oxidative desulfurization (ODS) of dibenzothiophene as a model sulfur compound. Ordered mesoporous carbon CMK-3 was synthesized via a two-step impregnation of the SBA-15 silica mesonanopores with a solution of sucrose using an incipient wetness method. The sucrose–silica composite was heated at 1173 K for 4 h under nitrogen flow. The silica template was dissolved in 5 wt.% hydrofluoric acid in order to remove the silica. The template-free carbon product thus obtained was filtered, washed with deionized water and ethanol and dried. Fe-CMK-3 was prepared by wetness impregnation using FeCl3.6H2O and FeNO3.9H2O as different sources of Fe. A solution of FeCl3.6H2O/ FeNO3.9H2O in ethanol was mixed with the carbon solution at room temperature. The solution was placed in a rotary evaporator to remove excess of ethanol at about 333 K and 60 rpm. Afterwards, the sample was dried at 373 K for 18 h and was thermally treated in a dynamic inert (N2) atmosphere. The percentage of Fe has been 2 wt.% with respect to carbon in the final FeCl3-CMK-3 and FeNO3-CMK 3 material. Porous carbon CMK-3 and the samples modified with Fe were characterized by XRD, FTIR, XPS, BET, TEM and SEM. These studies indicated that it was possible to obtain a CMK-3 replica successfully from SBA-15, using sucrose as a carbon precursor. Wide angle XRD pattern of the sample modified with FeCl3.6H2O implies the formation of the magnetite phase in the silica channels. The surface areas were 1320 m2/g for the CMK-3 and 1240 m2/g and 609 m2/g for FeCl3- CMK-3 and FeNO3-CMK-3, respectively. While the nanomaterial area is significantly smaller with the incorporation of the metal, CMK-3`s characteristic structure is maintained after the metal is within the host, in agreement with the XRD studies. The catalytic activity was improved when the nanoporous carbon was modified with Fe. The sample modified with FeCl3.6H2O was the most active catalyst for ODS of DBT, using hydrogen peroxide (H2O2) as oxidant and acetonitrile as solvent. 100% of DBT elimination was attained at a short time in mild conditions.Item Nanostructured SBA-15 host: synthesis, characterization and application in ketorolac-tromethamine release system.(Univesidsad Tecnológica Nacional, 2016) Cussa , jorgelina; Juárez , Juliana María; Gómez Costa, Marcos Bruno; Anunziata , Oscar Alfredo; Anunziata , Oscar Alfredo; Juárez , Juliana MaríaThe ordered mesoporous silica SBA-15 has been applied in studies of ketorolac tromethamine adsorption and release. The SBA-15 materials with hexagonal and regular structure were obtained using a triblock copolymer Pluronic P123 as template and TEOS as a silica source[1]. Drug delivery is an emerging field mainly focused on aiming drugs. The goal of this targeted delivery is to transport an amount of drugs to desirable sites (such as tumors and diseased tissues) while minimizing unwanted side effects of the drugs on other tissues [2]. Controlled drug delivery systems can achieve precise spatial and temporal delivery of therapeutic agents to the target site. Ketorolac tromethamine was adsorbed into SBA-15 silica nanochannels using ethanol as solvent. The physicochemical and textural properties of SBA-15 and ketorolac tromethamine/SBA-15 were characterized by X-ray diffraction, thermogravimetric analysis, transmission electron microscopy, Fourier transform infrared spectroscopy and BET surface studies. Drug release was evaluated by soaking the loaded silica mesoporous material into a solution of HCl (0.1N) at 37 ºC under continuous stirring. Release studies were performed in order to evaluate the required therapeutic efficacy. SBA-15 provides significant improvement in the controlled release of ketorolac tromethamine [3]. In this work, we have shown a promising drug storage material for the effective encapsulation and controlled release of KETO, achieving the required therapeutic efficacy. SBA-15/KETO shows characteristic bands of both, drug materials and the inorganic framework. This indicates that KETO was adsorbed into SBA-15 channel surface without affecting the chemical structure or composition of KETO. The study also demonstrates the storage capacity and release properties of SBA-15 containing KETO. The release of KETO contained in SBA-15 can offer significant improve in controlled drug release and enhance a good analgesia effect.Item Preparation and characterization of activated CMK-3 modified with vanadium applied in hydrogen storage.(Univesidsad Tecnológica Nacional, 2024) Juárez , Juliana María; Gómez Costa, Marcos Bruno; Cussa , jorgelina; Anunziata , Oscar Alfredo; Anunziata , Oscar Alfredo; Cussa , jorgelinaThe aim of this work is to synthesize a nanostructured Carbon CMK-3 modified with V in order to increase its capacity in hydrogen storage. The approach that we have followed includes synthesis of nanostructures with the experimental study of its adsorption capacity and storage properties. Ordered nanoporous carbon CMK-3 was synthesized via a two-step impregnation of the SBA-15 mesopores with a solution of sucrose using an incipient wetness method. The sucrose–silica composite was heated at 1173 K for 4 h under nitrogen flow. The silica template was dissolved with 5 wt% hydrofluoric acid in order to remove the silica. The template-free carbon product thus obtained was filtered, washed with deionized water and ethanol, and dried. [1] V-CMK-3 was prepared by wetness impregnation using VCl3 as source of Vanadium in order to increase the amount of hydrogen adsorbed. The sample of V-CMK-3 was treated under H2 flow two times at 1173 K. Porous carbon CMK-3 and the sample modified with V were characterized by XRD, FTIR, XPS, BET, TEM and SEM. These studies indicate that it was possible to obtain a CMK-3 replica successfully from SBA-15, using sucrose as a carbon precursor. [2] The surface areas are 1320 m2/g and 1050 m2/g for CMK-3 and V-CMK-3, respectively. While the nanomaterial area is significantly smaller with the incorporation of the metal, CMK-3`s characteristic structure is maintained after the metal is within the host, in agreement with the XRD studies. Measurements of hydrogen adsorption at cryogenic temperatures and low pressures were performed. The nanoparticles of V incorporated onto the nanostructured carbon CMK-3 showed higher hydrogen uptake at low and high pressures than CMK-3. (3.4 wt% and 2.2 wt% respectively of H2 sorption at 10 bar and 77 K).Item Mesoporous Cellular Foam (MCF): an efcient and biocompatible nanomaterial for the controlled release of Chlorambucil.(Univesidsad Tecnológica Nacional, 2022) Juárez , Juliana María; Cussa , jorgelina; Gómez Costa, Marcos BrunoNanotransporters have entered a great deal of exploration attention because of their promising openings in medicine delivery. We propose in this work, the Mesostructured siliceous cellular (MCFs) nanomaterial as a promising new hostfor drug delivery systems because both their specific physicochemical properties, in addition to the high biocompatibility, biodegradability, and low toxicity, make them seductive for controlled medicine release operations. Chlorambucil, is used as a chemotherapy drug administered for treating some types of cancer, chronic lymphocytic leukemia, low-grade non Hodgkin’s lymphoma, Hodgkin’s lymphoma and ovarian cancer. Chlorambucil-loaded Mesostructured cellular foam (MCF-CLB) was prepared and characterized by XRD, TEM, UV Vis DRS, FTIR, and texture analysis determining the adsorption capacity and its release, achieving the required therapeutic efficacy. The release of the drug was conducted by simulating the physiological conditions to reproduce the conditions of the organism. The mechanism of drug release from the MCF-CLB host was evaluated. Different mathematical models were used to adjust the experimental data, the best model describing the phenomenon under study over the entire period is the Weibull model. The auspicious results we attained for the release of the drug using the new material. The main advantage of this release is that the rate of release is fast at the beginning and then gradually decreases until 24 h practically all the drug contained in the carrier is released (>95%).Item LP-SBA-15/Ketorolac Nanocomposite: Development, Characterization, and Mathematical Modeling of Controlled Keto Release.(Univesidsad Tecnológica Nacional, 2023) Cussa, jorgelina; Juárez , Juliana María; Gómez Costa, Marcos Bruno; Anunziata, Oscar AlfredoDrug-controlled release systems can keep the level of drugs in precise doses in the body above the optimal level and with low toxicity. We propose the nanomaterial LP-SBA-15 as an attractive new host for drug delivery systems due to its high biocompatibility, in vivo biodegradability, and low toxicity. LP-SBA-15/Ketorolac was prepared and characterized by XRD, FTIR, UV-Vis DRS, TEM, and texture analysis, determining the adsorption capacity and its release and achieving the required therapeutic efficacy. The host shows the ordered mesoporous nanochannels with a diameter of 11-12 nm, maintaining the structure with the incorporation of Keto. The mechanism of drug release from the LP-SBA-15 host was evaluated. Different mathematical models were used to adjust the experimental data, the Ritger-Peppas model followed by the Weibull model the best ones. The promising results we obtained for the release of the drug thoroughly using the new material, reaching a rapid initial release rate, and maintaining a constant rate afterward, allow us to maintain the concentration of the drug in the therapeutic efficacy range, applying it largely to the treatment of diseases that require a rapid response.Item Controlled drug release system: cyclophosphamide delivery contained in LP-SBA-15 functionalized with tertbutylamine.(Univesidsad Tecnológica Nacional, 2023) Cussa, Jorgelina; Juárez , Juliana María; Gómez Costa, Marcos Bruno; Anunziata, Oscar Alfredo; Anunziata, Oscar Alfredo; Juárez , Juliana MaríaControlled drug administration systems can keep the level of drugs in specific locations in the organism with low toxicity and above the optimal level. We suggest the LP-SBA15 material as a auspicious new host for drug delivery systems because of its low toxicity high biocompatibility and in vivo biodegradability. LP-SBA-15 materials were synthesized and functionalized using 0-15-30% of tert-butylamine (TBA) and used as effective drug delivery systems. The anticancer drug Cyclophosphamide (CP) is an alkylating compound which is a phosphoramide derivative and is habitually used in autoimmune diseases. Reactive oxygen species production has been related to the mechanism of CP-induced cell death or tumor cell killing. The activated metabolites of CP are released in both healthy and tumor tissues and destroy the cellular DNA and proteins as well as mitochondrial and lysosomal membranes. CP was loaded into the nanomaterial of the transporters and characterized by XRD, FTIR, TGA, TEM and texture, determining the adsorption capacity and its release. The release of the drug was studied for each material by simulating the physiological conditions and submerging the composite, at 37 °C with constant stirring, in a HCl solution (0.1 M) for the first two hours and in Buffer solution pH = 7 the following hours to simulate the conditions of the organism. Release experiment were conducted to determine the requisite efficacy of treatment. The study was performed by UV-Vis spectrophotometry to evaluate the amount of CP released. The mechanism of drug release from the LP-SBA-15 matrix was evaluated by adjusting the experimental data, being the Ritger-Peppas. The promising results we obtained for the controlled release of the drug in a controlled manner using the new material, reaching a quick initial release rate and maintaining a constant rate at high moments, allow us to keep the concentration of the drug in the therapeutic efficacy range, applying it to a great extent to the treatment of diseases that require a rapid response. Lastly, it was suggested that the LP-SBA-15 nanomaterial functionalized with 15% TBA was the most desirable system due to they had adequate amounts of both drug loading and release.