Encapsulation of the natural antioxidant of sweet potato (Ipomoea batata) in biodegradable PLA nanoparticles

The encapsulation of active ingredients in colloidal nanocarriers has interesting potential to be used in controlled release. In particular, it is well know the interest of the different industries, such as pharmaceutical, food and cosmetic in the encapsulation of active principles in different types of nanoparticles (NPs). The goal of this research is focused in the possibility of encapsulation of natural antioxidants in biodegradable polymer nanoparticles.EEA San PedroFil: Guerrero, Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Investigación en Hidratos de Carbono (CIHIDECAR); Argentina.Fil: Corbino, Graciela Beatriz. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria San Pedro; ArgentinaFil: D´Accorso, Norma Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Investigación en Hidratos de Carbono (CIHIDECAR); Argentina.Fil: García, Nancy L. Consejo Nacional de Investigaciones Científicas y Técnicas. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Investigación en Hidratos de Carbono (CIHIDECAR); Argentina

Nanofibras de celulosa a partir de batata INTA (Ipomoea batatas) y caña tacuara argentina (Guadua angustifolia)

Las Nanofibras de Celulosa (CNF) tienen la capacidad de servir de refuerzo y formar materiales compuestos con sistemas dinámicos que están mostrando un enorme potencial para mejorar significativamente las tecnologías actuales, y encontrar nuevas y sorprendentes aplicaciones.El objetivo de este trabajo es aislar y caracterizar nanofibras de celulosa de batata (Ipomoea Batatas) y caña tacuara (Guada Angustafolia)EEA San PedroFil: García, Nancy Lis. Universidad Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones en Hidratos de Carbono; ArgentinaFil: D´Accorso, Norma. Universidad Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Orgánica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones en Hidratos de Carbono; ArgentinaFil: Dufresne, Alain. Université Grenoble Alpes. Centre National de la Recherche Scientifique Alpes; FranciaFil: Corbino, Graciela Beatriz. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria San Pedro; ArgentinaFil: Rol, Fleur. Université Grenoble Alpes. Centre National de la Recherche Scientifique Alpes; FranciaFil: Rodríguez Ramírez, Carlos A. Universidad Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones en Hidratos de Carbono; Argentin

High-Energy Dissipation Performance in Epoxy Coatings by the Synergistic Effec of Carbon Nanotube/Block Copolymer Conjugate

Hierarchical assembly of hard/soft nanoparticles holds great potential as reinforcements for polymer nanocomposites with tailored properties. Here, we present a facile strategy to integrate polystyrene-grafted carbon nanotubes (PSgCNT) (0.05-0.3 wt %) and poly(styrene-b- [isoprene-ran-epoxyisoprene]-b-styrene) block copolymer (10 wt %) into epoxy coatings using an ultrasound-assisted noncovalent functionalization process. The method leads to cured nanocomposites with core-shell block copolymer (BCP) nanodomains which are associated with carbon nanotubes (CNT) giving rise to CNT-BCP hybrid structures. Nanocomposite energy dissipation and reduced Young's Modulus (E∗) is determined from force-distance curves by atomic force microscopy operating in the PeakForce QNM imaging mode and compared to thermosets modified with BCP and purified carbon nanotubes (pCNT). Remarkably, nanocomposites bearing PSgCNT-BCP conjugates display an increase in energy dissipation of up to 7.1-fold with respect to neat epoxy and 53% more than materials prepared with pCNT and BCP at the same CNT load (0.3 wt %), while reduced Young's Modulus shows no significant change with CNT type and increases up to 25% compared to neat epoxy E∗ at a CNT load of 0.3 wt %. The energy dissipation performance of nanocomposites is also reflected by the lower wear coefficients of materials with PSgCNT and BCP compared to those with pCNT and BCP, as determined by abrasion tests. Furthermore, scanning electron microscopy (SEM) images taken on wear surfaces show that materials incorporating PSgCNT and BCP exhibit much more surface deformation under shear forces in agreement with their higher ability to dissipate more energy before particle release. We propose that the synergistic effect observed in energy dissipation arises from hierarchical assembly of PSgCNT and BCP within the epoxy matrix and provides clues that the CNT-BCP interface has a significant role in the mechanisms of energy dissipation of epoxy coating modified by CNT-BCP conjugates. These findings provide a means to design epoxy-based coatings with high-energy dissipation performance.Fil: Garate, Hernán. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones en Hidratos de Carbono. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Investigaciones en Hidratos de Carbono; ArgentinaFil: Bianchi, Micaela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; ArgentinaFil: Pietrasanta, Lia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; ArgentinaFil: Goyanes, Silvia Nair. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; ArgentinaFil: D`accorso, Norma Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones en Hidratos de Carbono. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Investigaciones en Hidratos de Carbono; Argentin

From superhydrophilic to superhydrophobic polymer-nanoparticles coated meshes for water-oil separation systems with resistance to hard water

A one-step procedure is presented for developing novel superhydrophobic oil-water separation membranes, based on composites of nanoparticles and polymers. The combination of hydrophilic particles with hydrophobic polymers allows obtaining superhydrophobic coatings on metal meshes, with chemical and physical stability. The methodology consists of coating SiO2 hydrophilic nanoparticles with two hydrophobic polymers (polydimethylsiloxane and polyvinylidene fluoride, PDMS and PVDF, respectively) on metal meshes. The nanoparticles generate roughness in the nanoscale, while the combination of PVDF and PDMS provides hydrophobicity, chemical resistance, and reinforce of mechanical properties. Membranes were characterized by XPS, SEM, TEM, FTIR, TGA, water-contact-angles (WCA) measurements, and elongation tests. The membranes present oil flux in the order of 102 Lm−2s−1, with stable performance during several months for water/oil separation tests when using saline (Na+, Cl−) and hard water (Ca+2, Mg+2) solutions. The synergetic mixture of three components, PDMS-PVDF-SiO2, provides superhydrophobic behaviour while coatings formed by any combination of only two components do not show the targeted properties.Fil: Sosa, Mariana Daniela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; ArgentinaFil: Canneva, Antonela. YPF - Tecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Kaplan, Andrea Edith. Universidad de Buenos Aires. Facultad de Odontología. Departamento de Materiales Dentales. Cátedra de Materiales Dentales; ArgentinaFil: D´accorso Norma Beatriz. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Orgánica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones en Hidratos de Carbono. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Investigaciones en Hidratos de Carbono; ArgentinaFil: Negri, Ricardo Martin. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Inorgánica, Analítica y Química Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; Argentin

Arapey sweet potato peel waste as renewable source of antioxidant: extraction, nanoencapsulation and nanoadditive potential in films

In this work, the peel of Arapey Sweet Potato (Ipomoea batatas), a vegetable waste, was used as a source of phenolic compounds which are widely recognized as beneficial antioxidants for human health. The extract obtained from Ipomoea batatas exhibited an antioxidant activity significantly higher than many antioxidant agents reported in literature (476.96 mg of TROLOX mL-1), as well as good thermal stability. Nanocapsules of the extract coated with low molecular weight polylactic acid were prepared by the emulsification-solvent evaporation method and the nanoparticles obtained were characterized physical; thermal; and morphologically. An analysis of the variables that were investigated to increase the encapsulation efficiency is presented here. Besides, PLA films prepared via the solution-casting method exhibited good compatibility with the nanoparticles loaded with the antioxidant extract, as was evidenced by the uniform and stable dispersion of these particles in the films. Furthermore, an improvement of the mechanical properties of the PLA films due to the presence of the nanoparticles were clearly observed. Results reported here are encourage enough to propose the nanocapsules described in this work as additives or to be used immersed in films for controlled release of antioxidants, putting in value a vegetable waste.EEA San PedroFil: Guerrero-León, Beatriz. Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales. Departamento de Química Orgánica; ArgentinaFil: Corbino, Graciela Beatriz. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria San Pedro; ArgentinaFil: Dufresne, Alain. Universite Grenoble Alpes. CNRS. Institut National Polytechnique de Grenoble; FranciaFil: Errea, María Inés. Instituto Tecnológico de Buenos Aires. Departamento de Ingeniería Química; ArgentinaFil: D´Accorso, Norma. Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales. Departamento de Química Orgánica; ArgentinaFil: D´Accorso, Norma. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones en Hidratos de Carbono (CIHIDECAR); ArgentinaFil: D´Accorso, Norma. Universidad de Buenos Aires. Centro de Investigaciones en Hidratos de Carbono (CIHIDECAR); ArgentinaFil: García, Nancy Lis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones en Hidratos de Carbono (CIHIDECAR); ArgentinaFil: García, Nancy Lis. Universidad de Buenos Aires. Centro de Investigaciones en Hidratos de Carbono (CIHIDECAR); Argentin

Development of carbohydrate functionalized magnetic nanoparticles for aminoglycosides magnetic solid phase extraction

Magnetic nanoparticles decorated with D-galactose and galactitol (Fe3O4@SiN-galactose and Fe3O4@SiN-galactitol) were synthesized and employed as sorbent in a magnetic solid phase extraction (MSPE) procedure prior the analysis of aminoglycosides (AGs) in honey samples by LC-MS/MS. AGs are broad spectrum antibiotics, characterized by aminosugars, widespread used in therapeutic and veterinary applications. AGs can be found in the environment and food of animal origin. Fe3O4@SiN-galactose and Fe3O4@SiN-galactitol were synthesized via copper catalyzed alkyne azide cycloaddition and the synthesis was efficiently followed by infrared spectroscopy. They were characterized by electron microscopy, thermogravimetric analysis and magnetization curves. The nature of the loading (acetonitrile:water, 50:50 v/v) and elution solution (formic acid 190 mM) were studied in order to optimize the MSPE. Quantitative difference between MSPE with Fe3O4@SiN-galactose and MSPE with Fe3O4@SiN-galactitol in terms of recovery was found. The final optimized method using Fe3O4@SiN-galactose and Fe3O4@SiN-galactitol was applied in the determination of AGs in honey. The MSPE performance of Fe3O4@SiN-galactitol was found to be superior to that of MSPE with Fe3O4@SiN-galactose. The limits of quantification were between 2 and 19 μg kg−1 for amikacin, dihydrostreptomycin, tobramicyn and gentamycin. A good correlation between predicted and nominal values of AGs in honey was found (trueness from 84% to 109%). This MSPE procedure not only requires a minimum amount of sorbent (1 mg) and sample (0.2 g), but it can also be accomplish in a rather short time.Fil: Contin, Mario Daniel. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Analítica y Fisicoquímica. Cátedra de Química Analítica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; ArgentinaFil: Quinsaat, Jose Enrico. Laboratory for Functional Polymers; SuizaFil: Negri, Ricardo Martin. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Inorgánica, Analítica y Química Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; ArgentinaFil: Tripodi, Valeria Paula. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Tecnología Farmacéutica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; ArgentinaFil: Opris, Dorina. Laboratory for Functional Polymers,; SuizaFil: D´Accorso, Norma Beatriz. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Orgánica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones en Hidratos de Carbono. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Investigaciones en Hidratos de Carbono; Argentin

Thermal treatment of the carbon nanotubes and their functionalization with styrene

In this work we studied the functionalization of commercially available multiwalled carbon nanotubes (MWCNT) (Nanocyl 3100) with polystyrene by the method so called "grafting from". The nanotubes were used as received and oxidized in air at 400 °C. The functionalization was started using thionyl chloride under reflux, followed by a reaction with ethylene glycol which allowed the inclusion of hydroxyl groups. The reaction of those with 2-chloropropionyl chloride led to the generation of the polymerization initiator. Last, the radical polymerization of the functionalized nanotubes, using styrene as the monomer, led to new materials which were studied with thermogravimetric analysis (TGA), Fourier transform infrared (FTIR) spectroscopy, transmission electron microscopy (TEM) and ultraviolet-visible (UV-vis) spectroscopy. © 2009 Elsevier B.V. All rights reserved.Fil: de Falco, Alejandro Diego. Universidad de Buenos Aires; ArgentinaFil: Fascio, Mirta Liliana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; ArgentinaFil: Lamanna, Melisa Elsa. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; ArgentinaFil: Corcuera, Maria A.. Universidad del País Vasco; EspañaFil: Mondragon, Iñaki. Universidad del País Vasco; EspañaFil: Rubiolo, Gerardo Hector. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; ArgentinaFil: D´Accorso, Norma Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; ArgentinaFil: Goyanes, Silvia Nair. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; Argentin

Game-changing restraint of Ros-damaged phenylalanine, upon tumor metastasis

Abstract An abrupt increase in metastatic growth as a consequence of the removal of primary tumors suggests that the concomitant resistance (CR) phenomenon might occur in human cancer. CR occurs in murine tumors and ROS-damaged phenylalanine, meta-tyrosine (m-Tyr), was proposed as the serum anti-tumor factor primarily responsible for CR. Herein, we demonstrate for the first time that CR happens in different experimental human solid tumors (prostate, lung anaplastic, and nasopharyngeal carcinoma). Moreover, m-Tyr was detected in the serum of mice bearing prostate cancer (PCa) xenografts. Primary tumor growth was inhibited in animals injected with m-Tyr. Further, the CR phenomenon was reversed when secondary implants were injected into mice with phenylalanine (Phe), a protective amino acid highly present in primary tumors. PCa cells exposed to m-Tyr in vitro showed reduced cell viability, downregulated NFκB/STAT3/Notch axis, and induced autophagy; effects reversed by Phe. Strikingly, m-Tyr administration also impaired both, spontaneous metastasis derived from murine mammary carcinomas (4T1, C7HI, and LMM3) and PCa experimental metastases. Altogether, our findings propose m-Tyr delivery as a novel approach to boost the therapeutic efficacy of the current treatment for metastasis preventing the escape from tumor dormancy