Facultad Regional Córdoba
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Item Reservorio nanoscópico de hidrógeno a partie de biorresiduos de cáscara de naranjas.(Univesidsad Tecnológica Nacional., 2022) Juárez , Juliana María; Ledesma , Brenda Cecilia; Anunziata , Oscar Alfredo; Gómez Costa , Marcos Bruno; Beltramone , Andrea Raquel; Anunziata , Oscar Alfredo; Ledesma , Brenda CeciliaEste trabajo aborda el enfoque de valorización de biorresiduos para el desarrollo de un novedoso nanomaterial carbonoso para ser utilizado en la adsorción de hidrógeno como una alternativa en el uso de hidrógeno verde. En esta investigación, los carbones activados se sintetizaron a partir de cáscara de naranja utilizando diferentes condiciones de síntesis. Con los carbones activados obtenidos con la mejor estructura y textura se estudió la adsorción de hidrógeno y los efectos en la meso/microporosidad de estos. La activación del carbón se realizó mediante un proceso químico con ácido fosfórico como agente activador, variando la concentración de ácido, la relación sustrato / agente activador y el tiempo de contacto entre ellos. El mejor material se obtuvo utilizando tiempo de carbonización de 1 h, temperatura de carbonización de 470oC, concentración de ácido fosfórico de 50% en peso y con área BET de 1402 m2 / g. Dicho material mejoró significativamente el comportamiento de almacenamiento de H2 en comparación con el carbón nanoestructurado del tipo CMK-3 (3,1% en peso a -196,15 oC y 10 bar). El material sintetizado es prometedor en la absorción de hidrógeno por fuerzas de enlace débiles (fisisorción).Item Sulfated/Zr-containing mesoporous carbons: a promising nanostructured catalytic material.(Univesidsad Tecnológica Nacional., 2021) Anunziata , Oscar Alfredo; Martínez , María Laura; Martínez , María LauraIn this work, we report the successful preparation of a promising material with acidic properties from starch-derived mesoporous carbon (SMC), functionalized with sulfated zirconia (SZr-SMC). The process of assembling P123, starch, zirconia, and silicon produces ordered mesoporous carbon modified with Zr. Reaction time and temperature are essential to avoid the appearance of poorly assembled or unsightly structures, reducing the surface area and the size of the pores. SZr- SMC has a surface area of approximately 1300 m2/g, and a total pore volume of 0.94 cm3/g, composed mainly of mesoporous with an average pore size of 3.5 nm. The composition of the surface and the chemical states of the elements did not reveal ZrO2 as isolated clusters. Ammonia thermodesorption studies indicated that, SZr-SMC retains 2.49 mmol/g of NH3 at very high temperature, exhibiting a strong acidity. According to the data collected by infrared spectroscopy (FTIR), of pyridine desorbed at various temperatures, the total number of acidic sites was 2.36 mmol/g, and the distribution in weak - medium, strong, and super acidic sites was determined. The activity in the methylation of aniline and isopropanol dehydration indicated that the acid sites are strong, and have not redox properties. A new and promising catalytic material based on mesoporous carbons modified with sulfated Zr is developed, which opens a wide range of acid-catalyzed reactions applied to industrial and medical processes.Item HaP/SBA-3 Nanostructured Composite to Remove Fluoride Effectively from Contaminated Water.(Univesidsad Tecnológica Nacional., 2021) Cussa , jorgelina; López, Claudia; Anunziata , Oscar Alfredo; Anunziata , Oscar Alfredo; López, ClaudiaElectron Microscopy (SEM), Transmission Electron Microscopy (TEM) and textural properties, were successfully applied to remove fluoride from contaminated water. The proposed procedure to prepare HaP/SBA-3 was successful, which acts as supports to anchor the HaP crystals, in nanometer-scale (<2nm), with higher fluoride retention from contaminated water. The free OH- groups of HaP nanocrystals, within the host, facilitated the high-performance fluoride trapping. The fluoride retention activity was much higher than that of pure HaP and the composites HaP/SBA-15 and HaP/MCM-41. Keywords: F- retention; Contaminated water; HaP/SBA-3; NanocompositesItem Controlled drug release system: cyclophosphamide delivery contained in LP-SBA-15 functionalized with terbutylamine.(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.Item Controlled Release of Haloperidol from a novel SWCNT Nano composite coated with ZnO nanocrystals.(Univesidsad Tecnológica Nacional., 2023) Anunziata , Oscar Alfredo; Cussa , jorgelina; Martínez , María Laura; Martínez , María Laura; Cussa , jorgelinaStarting from the physicochemical knowledge of the host properties of the na noscale systems would be applied to drug dosage [1,2]. We propose NM synthesis strategies that offer the necessary characteristics for these processes. First, we study the physicochemistry of the anchoring sites of the respective hosts (chemical bonds with reversible or irreversible adsorption) or physisorption (straightforward interactions). Then, whether to design carbon based nanomaterials (CNM), or nano engineered materials, containing the respective active sites (deposited or generated nanospecies), capable of interacting with the aforementioned hosts such as: redox sites, proton acceptor sites, electron donor-acceptor sites, to allow HOMO-LUMO chemical interactions that satisfy the needs of the process to be studied. The nanostructures that allow free diffusions and reversible adsorptions, dosage of molecules with applications in nanokinetics, etc., and determination of critical molecular sizes, calculated using experimental methods, and methods such as density functional theory and semiempirical methods, to avoid steric hindrances between molecules and 100 80 40 60 8 12 16 20 Experimental data Weibull Ritger-Peppas Higuchi Drug Released , % mol/w Time (h) 4 20 nanomaterials whether 2D or 3D, designing NMs with large surface area, physical, ther mal and chemical stability, and pore size, and adequate pore size. Advancing in this sense, this work studies the usage of: Haloperidol Release from ZnO nanocrystal Coated SWCNT, with 30nm of wide and 5 um of long, which by the effect of the interaction between the host and drug molecules and by diffusion through the porosity, leads to a substantial contribution to controlled drug release. The reduction in the dose and frequency of administration, possible improvement in the selectivity of the pharmacological activity, and a prolonged therapeutic effect. CNT prepared by sol gel method (using the same technique describe by us, [3]), but at different pH and long range of pristine mesoporous carbons material calcination, to obtain SWCNTs. The posterior deposition of ZnO, was obtained, employing ZnNO3, activated under N2 flow at 500ºC; offering adequate LUMO of Zn (the hybridized MO) for Haloperidol interactions. Haloperidol competitively blocks postsynaptic dopamine (D2) receptors in the meso limbic system of the brain, thereby eliminat ing dopamine neurotransmission and leading to antidelusionary and antihallucinagenic effects. Specifically, the dose of Haloperidol (potent antipsychotic drug), indicates that its release follows the so called "power law" or Weibull model, based on the results we obtained in our laboratoryItem Major challenges for Nanoscience and Nanotechnology in Health for sustainability.(Univesidsad Tecnológica Nacional., 2022) Anunziata , Oscar AlfredoThis paper covers the physicochemical basis of studies of the structure and properties of inorganic and organic nanomaterials, advances in synthesis, processing, characterization and testing, design of Nano engineered materials and systems, and applications in technology, focusing on working atoms to individual atoms, anchored, deposited or grafted onto Carbon nanotubes and Mesoporous Carbons Keywords” “Nano Materials“,“Nanoscience“ and “Nanotechnology“,“H2 Uptake”, “Water purification“, “Drug Delivery“, ”Atom by Atom”, “Hole Electrons”Item Novel mesoporpous carbon modified with zirconia for hydrogen adsorption.(Univesidsad Tecnológica Nacional., 2021) Venosta, Lisandro; Juárez , Juliana María; Anunziata , Oscar Alfredo; Gómez Costa, Marcos Bruno; Anunziata , Oscar Alfredo; Juárez , Juliana MaríaNanostructured carbon material (CMK-3) modified with zirconium oxide was synthesized by a new direct synthesis technique. Zirconium oxide dispersed in carbon materials (Zr-CMK-3) were characterized by X-ray diffraction, textural properties, UV-Vis-DRS, XPS, and transmission electron microscopy analysis. The goal of this new synthesis method is to avoid the use of inorganic siliceous template (SBA-15), which leads to a shorter and cheaper way to obtain mesoporous carbon, and at the same time incorporate into the framework Zirconium atoms. Zr-CMK-3 material significantly improved H2 storage behaviour (4.6% by weight at 77 K and 10 bar) compared to CMK-3 support. The synthesized material is promising in the absorption of hydrogen by weak bonding forces (physisorption). The activity of the samples to the adsorption of hydrogen molecules is attributed to the improved dispersion of the zirconium oxide, as well as the appropriate use of support, which can probably disperse the zirconium on its large surface area, allowing a great dispersion of the zirconium. The Zr+4 cation is an active species to absorb and store hydrogen through a physisorption process and the carbon plays an important role in the dispersion and size of metal particles. A hydrogen storage mechanism on the active surface of the ZrO2 clusters was proposed. First layer of hydrogen molecules can react with the metal cation through a dihydrogen complex (Kubas interaction). The second layer of hydrogen molecules adsorbed around the metal oxide clusters is due to dipole-like interactions, this is because the metal particle induces dipole forces on the hydrogen molecule. The other layers could also interact by dipole forces; however, the interaction force decreases as the distance to the surface increases. The upper layers could interact with the metal cation by dipole-induced bonding; however, the interaction force decreases as the distance to the surface increases.Item Síntesis directa del carbón mesoporoso ordenado CMK-3 modificado con circonio en almacenamiento de energía.(Univesidsad Tecnológica Nacional., 2020) Venosta, Lisandro; Juárez , Juliana María; Anunziata , Oscar Alfredo; Gómez Costa , Marcos Bruno; Anunziata , Oscar Alfredo; Juárez , Juliana MaríaEn este trabajo, informamos la síntesis y caracterización del material de carbono nanoestructurado (CMK-3) modificado con óxido de circonio sintetizado por una nueva técnica de síntesis directa. Este material es prometedor en la aplicación de adsorción de hidrógeno para el almacenamiento de energía. Los materiales con óxido de circonio (Zr-CMK-3) se sintetizaron con éxito y se caracterizaron por difracción de rayos X, propiedades texturales, UV-Vis-DRS, XPS y análisis de microscopía electrónica de transmisión. El material Zr-CMK-3 mejoró significativamente el comportamiento de almacenamiento de H2 (4,6% en peso a 77 K y 10 bar) en comparación con el soporte CMK-3. El material sintetizado es prometedor en la absorción de hidrógeno por fuerzas de enlace débiles (fisisorción). Se propuso un mecanismo de adsorción de hidrógeno y se discutió el rol de catión Zr+4 en la absorción de hidrógeno. Palabras clave: Circonio, CMK-3, Hidrógeno, Almacenamiento, EnergíaItem Superacid Mesoporous Carbons Based on Sulfated Zr.(Univesidsad Tecnológica Nacional., 2020) Anunziata , Oscar Alfredo; Martínez , María Laura; Martínez , María LauraIn this brief communication we report the successful preparation of a promising material with acidic properties from starch-derived mesoporous carbon (SMC), functionalized with sulfated zirconia. The process of assembling P123, starch, zirconia and silicon produces ordered mesoporous carbon modified with Zr. Reaction time and temperature are essential to avoid the appearance of poorly assembled or unsightly structures, reducing the surface area and the size of the pores. Zr-SMC has a surface area of approximately 1300 m2 g -1 , and the total pore volume of 0.94 cm3 g -1 , composed mainly of mesopores with an average pore size of 3.5 nm. The composition of the surface and the chemical states of the elements did not reveal ZrO2 as isolated clusters. Through the thermodesorption of the pre adsorbed ammonia in the sulfated Zr-SMC, the total ammonia retained is 1.80 mmol / g at high temperature, exhibiting medium to strong acidity.Item HaP/LP-SBA15 Nanocomposite for efficient removal of fluoride from contaminated water.(Univesidsad Tecnológica Nacional., 2020) López, Claudia; Cussa, jorgelina; Anunziata , Oscar Alfredo; Anunziata , Oscar Alfredo; Cussa, jorgelinaHydroxyapatite (HaP) composites and highly ordered large pore mesoporous silica, such as LP-SBA 15 (Large Pore-SBA-15), were developed, characterized by XRD, BET, FTIR, and HRTEM, applied to fluoride removal from contaminated water. The proposed procedure to prepare HaP/LP-SBA-15 was successful, which acts as supports to anchor the HaP crystals, in nanometer-scale (<12 nm), with higher fluoride retention from contaminated water. The free OH- groups of HaP nanocrystals, inside the host, permitted fluoride retention with high capacity. The fluoride holding activity was over 3 orders of magnitude higher than pure HaP.