Facultad Regional San Francisco

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Author: search.filters.author.Busatto, Carlos AlbertoHas files: Yes

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    Bio-composite Films Based on Alginate and Rice Husk Tar Microparticles Loaded with Eugenol for Active Packaging
    (2022-01-29) Taverna, María E.; Busatto, Carlos Alberto; Saires, Paula J.; Bertero, Melisa Paola; Sedran, Ulises A.; Estenoz, Diana
    This work focused on the valorization of tar derived from rice husk pyrolysis as a precursor of matrices for the encapsulation of active principles. In this regard, the development of novel films based on alginate and eugenol-loaded tar microparticles with suitable mechanical properties and antibacterial activity was studied. Tar microparticles loaded with eugenol were incorporated into sodium alginate films and the effect on the mechanical, thermal and humidity resistance properties were determined, as well as the antimicrobial activity. Films with different crosslinking degrees were also prepared using CaCl2, and the eugenol controlled release profiles were evaluated. Crosslinked films exhibited improved mechanical and humidity resistance properties, as well as a lower release rate of eugenol in water. The antimicrobial studies showed that eugenol-loaded films present a higher antimicrobial activity against Staphylococcus aureus. Alginate/eugenol-loaded tar microparticles composites showed an enhancement of antibacterial properties and suitable physical characteristics to be used in active packaging applications.
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    Morphology modulation of silica mesoporous nano- and microparticles for atrazine - controlled release
    (2022-06-09) Fookes, Federico A.; Busatto, Carlos Alberto; Taverna, María E.; Casis, Natalia; Lescano, Maia Raquel; Estenoz, Diana
    Atrazine is a moderately toxic triazine, used as a selective pre- and post-emergence herbicide. After application, it remains in the environment due to its low biodegradability causing severe environmental effects. Several controlled release systems have been proposed in order to minimize the negative impact of the herbicide on the environment. In particular, mesoporous silica nanoparticles have shown great potential in the agricultural area due to their controlled size and porosity, high surface area and non-toxicity. In this work, silica nano- and microparticles were synthesized and evaluated as atrazine delivery systems. The morphology and size distribution of the particles were characterized using dynamic light scattering (DLS) and scanning electron microscopy (SEM). The release profiles were studied by in vitro assays in water. In addition, phytotoxicity tests were performed using Lactuca sativa seeds. The mesoporous nano- and microparticles exhibited sustained release for at least 24 h and reduced phytotoxicity compared to free atrazine.
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    Supernucleation dominates lignin/poly(ethylene oxide) rystallization kinetics
    (2022-08) Taverna, María E.; Altorbaq, Abdullah S.; Kumar, Sanat K.; Olmedo-Martínez, Jorge L.; Busatto, Carlos Alberto; Zubitur, Manuela; Mugica, Agurtzane; Nicolau, Verónica V.; Estenoz, Diana; Müller, Alejandro J.
    The effect of lignin nanoparticles (LNPs) on the crystallization kinetics of poly(ethylene oxide) (PEO) is examined. Lignin from spruce and ionic isolation was used to prepare LNPs with a number-averaged diameter of 85 nm (with a relatively large polydispersity) by an ultrasonication method. PEO-based nanocomposites with four different LNP contents (5, 10, 15, and 20 wt %) were prepared and subject to isothermal and nonisothermal crystallization protocols in a series of experiments. Scanning electron microscopy (SEM) images showed welldispersed LNPs in the crystallized PEO matrix. The incorporation of LNPs exponentially increases nucleation density at moderate loadings, with this trend apparently saturating at higher loadings. However, the spherulitic growth rate decreases monotonically with LNP loading. This is attributed to the substantial PEO/LNP affinity, which impacts chain diffusion and induces supernucleation effect (with efficiencies in the order of 200%), but leads to slower growth rates. The overall crystallization kinetics, measured by the DSC, shows faster nanocomposite crystallization rates relative to the neat PEO at all LNP contents examined. This indicates that the supernucleation effect of LNPs dominates over the decrease in the growth rates, although its influence slightly decreases as the LNP content increases. The strong hydrogen-bonded interactions between the LNPs and the PEO are thus reminiscent of confinement effects found in polymer-grafted NP nanocomposites (e.g., PEO-g-SiO2/ PEO) in the brush-controlled regime.
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    Efecto de la incorporación de nanopartículas de lignina iónica en la cristalización de polióxido de etileno
    (2020-04) Taverna, María E.; Olmedo, Jorge; Busatto, Carlos Alberto; Zubitur, Manoli; Nicolau, Verónica V.; Estenoz, Diana; Müller, Alejandro J.
    El polióxido de etileno (POE) es un poliéter semicristalino cuya cinética de cristalización ha sido ampliamente estudiada tanto en el componente puro como en sus mezclas con otros polímeros amorfos y semicristalinos. Se han investigado materiales compuestos basados en mezclas de POE y lignina (polímero natural, amorfo, abundante y de bajo costo). La mezcla eficiente de estos polímeros depende en gran medida de la compleja estructura de la lignina. Se ha reportado la cinética de cristalización de la mezcla de POE y lignina proveniente de procesos de aislamiento Alcell y/o Kraft.2 En este trabajo se estudia la síntesis de nanopartículas de lignina de origen iónico y su empleo en la obtención de mezclas con POE. Específicamente, se evalúa la influencia de nanopartículas en la cinética de cristalización del POE.
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    Empleo de Macropartículas de quitosano entrecruzadas con TPP como refuerzo en resinas epoxi basadas en DGEBA
    (Secyt UTN Facultad Regional San Francisco, 2019-10) Ruiz Miraglio, Sofía; Taverna, María E.; Busatto, Carlos Alberto; Helbling, I.; Estenoz, Diana; Nicolau, Verónica V.
    Las resinas epoxi son materiales poliméricos, que presentan en su estructura uno o más anillos conocidos como epoxi, epóxido, u oxirano. Más del 75% del volumen de ventas de resinas epoxi corresponde a las derivadas bifuncionales del diglicidil éter de bisfenol A (DGEBA). Estas resinas poseen excelente adhesividad, poder aislante, resistencia mecánica, térmica, y a solventes. En este trabajo se obtuvieron y caracterizaron micropartículas de quitosano entrecruzadas con tripolifosfato de sodio (TPP) para su empleo en la obtención de resinas basadas en DGEBA curadas con mezclas de poliamidas.
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    Preparación y caracterización de nano- y micropartículas de sílice para la liberación controlada de atrazina
    (AJEA- Actas de Jornadas y Eventos Académicos de UTN, 2021-11-29) Fookes, Federico A.; Busatto, Carlos Alberto; Taverna, María E.; Lescano, Maia Raquel; Estenoz, Diana
    La atrazina (2-cloro-4-etilamina-6-isopropilamina-s-triazina) es una triazina moderadamente tóxica, utilizada como herbicida selectivo de pre y post-emergencia. Después de su aplicación permanece en el medio ambiente debido a su baja biodegradabilidad y larga vida media en agua (entre 30 y 100 días). A fin de reducir el impacto ambiental de estos herbicidas se han empleado matrices orgánicas e inorgánicas para el desarrollo de sistemas de liberación controlada. Dentro de las matrices inorgánicas, se han evaluado las nanopartículas de sílice mesoporosas debido a su porosidad y elevada área superficial. En este trabajo se prepararon y caracterizaron nano- y micropartículas de sílice para la encapsulación de atrazina. Se evaluó el perfil de liberación mediante ensayos in vitro en agua y, además, se realizaron ensayos de fitoxicidad en semillas de lechuga. Se observó que las nanopartículas mesoporosas presentan una liberación sostenida por al menos 24 h y una fitotoxicidad reducida
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    Preparation and Characterization of Lignin Microparticles-in-Alginate Beads for Atrazine Controlled Release
    (2019-09-21) Busatto, Carlos Alberto; Taverna, María E.; Lescano, Maia Raquel; Zalazar, Cristina; Estenoz, Diana
    The use of lignin as polymeric matrices for controlled release systems in agriculture is a promising alternative for its reval-orization. In this work, diferent atrazine delivery systems were studied. Lignin derived from ionic isolation was used for the preparation of atrazine-loaded microparticles by the solvent extraction/evaporation and microfuidic techniques. Micropar-ticles were also encapsulated in sodium alginate beads. Lignin microparticles prepared by microfuidics presented a larger particle size, higher encapsulation efciency and a narrow size distribution. The in vitro release of atrazine was evaluated in water. Atrazine release from microparticles prepared by the solvent extraction/evaporation technique showed a signifcant burst release, and this efect was reduced by incorporating microparticles within alginate beads. In addition, the phytotoxicity of the systems was evaluated employing Lactuca sativa seeds. The phytotoxicity results showed that lignin-based formula- tions are safe according to the parameters evaluated, in contrast with commercial atrazine that resulted phytotoxic.
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    Microparticles based on ionic and organosolv lignins for the controlled release of atrazine
    (Journal of Hazaourdos Materials, 2018-07-02) Taverna, María E.; Busatto, Carlos Alberto; Lescano, Maia Raquel; Nicolau, Verónica V.; Zalazar, Cristina; Meira, Gregorio; Estenoz, Diana
    Lignins are natural polymers of the lignocellulosic biomass. Nowadays, there is a growing interest in developing value-added products based on lignins due to their renewability, low cost and abundance. In this work, lignin microspheres from organosolv and ionic isolation processes were prepared for the controlled release of atrazine. Microspheres were prepared by the solvent extraction/evaporation technique. The controlled release of atrazine from organosolv and ionic lignins microparticles was studied in water. Mobility experiments were performed in an agricultural soil from Argentina. The results showed that microparticles prepared using dichloromethane as the dispersed phase were spherical, while lignins dispersed in ethyl acetate produce irregular microparticles. Organosolv lignin microparticles presented higher encapsulation efficiency for all herbicide loads. About 98% and 95% of atrazine was released in 24 and 48h approximately from organosolv and ionic lignin microparticles, respectively. The release profiles of atrazine from both lignin microparticles were not affected by the herbicide load. Atrazine mobility experiments in soil showed that about 80% of free atrazine was leached in 37 days, while 65.0% and 59.7% of the herbicide was leached from ionic and organosolv lignin microparticles, respectively. Thus, atrazine-loaded microparticles could reduce leaching compared to a commercial formulation of free atrazine.