Browsing by Author "Pavez Guerrero, Paulina"

Now showing 1 - 3 of 3
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    A comparative study on the cucurbit[7]uril-based indicator displacement assay for methyl Viologen. A theoretical and experimental perspective
    Pavez Guerrero, Paulina; Fierro Huerta, Angelica Maria; Rojas Guerrero, Mabel Natalia; Garcia-Rio, Luis; Dinamarca-Villarroel, Luis; Fuentealba Patino, Denis Alberto; Droguett Muñoz, Kevin Arturo; Santos Blanco, José Guillermo; Aliaga Miranda, Margarita Elly
    One colorimetric and one fluorescent-indicator displacement assay (IDA) were studied to assess their interaction with methyl viologen (MV), an herbicide commercially known as paraquat. The host–guest complexes formed by cucurbit[7]uril (CB[7]) and the 4-nitroaniline (NA) or Berberine (Be) dyes function as colorimetric- and fluorescent-IDA for MV, respectively. The CB[7]@NA and CB[7]@Be complexes were characterized by UV–vis, fluorescence spectroscopy, and dynamic simulations. Isothermal titration calorimetry (ITC) experiments and dynamic simulations were employed to obtain thermodynamic data for the formation of the 1:1 inclusion complexes. Finally, NA is proposed as a reference colorimetric dye for determining CB[7]-binding affinities using competitive host–guest titrations, and the fluorescent-IDA as the best assay proposed, as it exhibits a high binding constant, a good detection limit of 2.7 × 10−6 mol L-1, good linearity in the range from 4 × 10−6 mol L-1 to 3.5 × 10−5 mol L-1, in aqueous solution.
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    Ética y seguridad en la investigación: aprendizajes y desafíos
    (Ediciones UC, 2022) Alarcón Bustos, Mariela; Arenas Morales, Verónica; Arévalo Nally, Constanza; Bonacic Salas, Cristián; Bravo Valenzuela, Paulina; Cabrera Oyarzún, Alejandro; Cáceres Soto, Nataly Edith; Caprile Etchart, Paola Francisca; Díaz Sacco, Alessandra; Gimpel Rivera, Jessica; Guzmán Durán, Ana María; Hilliger Carrasco, Isabel; Ibacache REyes, Felipe Andrés; López González, Dany; Martínez Pereira, Alejandra; Medina Silva, Rafael; Miranda Molina, Carlos Alberto; Muñoz Baeza, Ana; Nogueira Llovet, Amanda Antonia; Pastén González, Pablo Arturo; Pavez Guerrero, Paulina; Ramaciotti Godoy, Clara; Ramos Vergara, Paulina; Roschzttardtz Choucroun, Hannetz France; Troncoso Troncoso, Carlos Patricio; Valera, Luca; Várgas Sepúlveda, Jonathan; Santana López, Alejandra Isabel; Valera, Luca
    ¿Por qué es importante y necesaria la ética de la investigación en Chile? Se convoca aquí a más de setenta académicos y profesionales a presentar sus reflexiones, orientaciones y aprendizajes asociados al resguardo ético y de la seguridad en investigación. Este libro permite una aproximación al quehacer de las universidades chilenas abordando las temáticas que moviluzan a los comités éticocientíficos y ofrece una panorámica de sus aportes en la formación de las buenas prácticas de investigación en las comunidades universitarias. Esta publicación constituye un aporte a la literatura en la gestión de la ética y seguridad en investigación académica desde y para un público hispanohablante que sin duda contribuirá a mejorar estrategias de gestión y desarrollo en estos ámbitos, además de contribuir a la construcción de una sociedad más humana y respetuosa del entorno social, cultural y natural, en el contexto de la generación de conocimientos de alto nivel.
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    Evaluating the Environmental Impacts of Nanocellulose Production using Conventional and Novel Approach at Laboratory Scale
    (2025) Talwar, Nishtha; Huerta Gajardo, Oscar; Millán, Daniela ; Pavez Guerrero, Paulina; Isaacs, Mauricio ; Holden, Nicholas M.
    Green chemistry promotes the design and application of chemical products and processes that reduce or preferably eliminate the use and generation of hazardous substances. The objective of this research was to evaluate the environmental performance of two methods of producing nanocellulose at the laboratory scale: (i) a conventional sulphuric acid hydrolysis that has been upscaled for industrial use (TRL 8-9); and (ii) the novel approach using the ternary eutectic mixture ChCl: pTSA: PA molar ratio (1:1:1.35) that is currently at TRL 2. The purpose of developing the new approach was to find a better alternative to the conventional process from an environmental perspective. To validate this, life cycle assessment was used to compare conventional vs novel methods with the functional unit of 1 g nanocellulose produced. The system boundary was from cradle to laboratory gate. The results were interpreted to select the best method for laboratory use and to identify design issues to address during upscaling of the novel method. For both methods, conventional and novel, the impact categories selected were climate change (kgCO2 eq), Acidification (kg SO2 eq), Ecotox Air (CTUe) and Eutrophication (kg N eq). To produce 1 g of nanocellulose with sulphuric acid caused a climate impact of between 68 kg CO2 eq (90% yield) to 105 kg CO2 eq (57% yield). Produced using DES the climate impact ranged from 85 kg CO2 eq.(90% yield) to 132 kg CO2 (57% yield). The results indicated that the novel method created greater impacts over the whole life cycle. Unless significant changes are made during upscaling, the novel method will not make a positive contribution to sustainable, circular bioeconomy. The method does have potential to be improved to reduce impact, including using decarbonised energy, a renewable, bio-based feedstock for the cellulose and choline chloride to improve the overall efficiency of using deep eutectic solvent (DES) at pilot scale. The low TRL life cycle assessment offered insights not possible if only the laboratory stage of the analysis had been considered.