DSpace Comunidad:
http://hdl.handle.net/10045/21801
2024-03-19T04:31:18ZEvaluation of highly adsorptive Guefoams (multifunctional guest-containing foams) as a potential sorbent for determination of volatile organic compounds (VOCs) by means of thermal desorption
http://hdl.handle.net/10045/141161
Título: Evaluation of highly adsorptive Guefoams (multifunctional guest-containing foams) as a potential sorbent for determination of volatile organic compounds (VOCs) by means of thermal desorption
Autor/es: Sánchez, Raquel; Beltrán Sanahuja, Ana; Maiorano Lauría, Lucila Paola; Todolí Torró, José Luis; Molina Jordá, José Miguel
Resumen: The present work delves into the feasibility of employing a novel structured sorbent referred to as GFAD (Guefoam Adsorption Device) for the determination of volatile organic compounds (VOCs) in liquid samples. The chosen method has been static headspace sorptive extraction-thermal desorption gas chromatography mass spectrometry (HSSE-TD-GC–MS). The GFAD comprises an aluminum cellular material with a distinct replication structure and a solid guest phase consisting of activated carbon particles dispersed within the cavities of the cellular aluminum. The extensive specific surface area, robustness, and exceptional thermal conductivity of this pioneering material offer distinct advantages over commercially available polydimethylsiloxane-based Twister® devices. Therefore, the trapping efficiency for volatile organic compounds is enhanced, and it is possible to perform the analysis of concentrated samples. According to computational simulations, it has been demonstrated that GFAD has a high heat conductivity. As a result, the desorption efficiency is improved, and minimal temperature gradients are generated throughout the GFAD during the heating process. Besides, the energy consumption is significantly lowered, thus aligning with environmentally conscientious and sustainable analytical practices. The experimental results give a proof of the suitability of the GFAD for determining gaseous compounds in liquid samples through HSSE-TD-GC–MS. For volatile species, the new material provides higher peak areas and lower limits of detection than a commercially available Twister® device. Furthermore, the GFAD is reusable, its adsorbing properties remaining unchanged during, at least, 100 consecutive analyses. In addition, unlike to the Twister®, no intense siloxane peaks are observed in the chromatograms obtained with the GFAD. The feasibility of qualitative and semi-quantitative analysis with the new accessory has been demonstrated with both standards and a cereal bioethanol real sample.2024-02-29T00:00:00ZAntioxidant water-resistant fish gelatin nanofibers: A comparative analysis of fructose and citric acid crosslinking and investigation of chlorogenic acid release kinetics
http://hdl.handle.net/10045/139708
Título: Antioxidant water-resistant fish gelatin nanofibers: A comparative analysis of fructose and citric acid crosslinking and investigation of chlorogenic acid release kinetics
Autor/es: Estevez-Areco, Santiago; Goyanes, Silvia; Garrigós, María del Carmen; Jiménez, Alfonso
Resumen: The use of bio-based and biodegradable electrospun mats encapsulating antioxidants is a promising strategy for creating innovative multi-layered food packaging materials, since the nanometric size of the fibers forming the mat maximizes the availability of the active compound. However, the development of water-resistant active electrospun mats using only non-toxic natural components remains a challenge. In this paper, water-resistant fish gelatin (FG) nanofibers incorporating chlorogenic acid (CGA), a natural antioxidant, were developed using either citric acid (CA) or fructose (F) as crosslinking agents. The CA-crosslinked fibers had a mean diameter of (200 ± 50) nm and a solubility in cold water of (28 ± 2)%, while F-crosslinked fibers were obtained with a mean diameter of (300 ± 50) nm and a solubility of (5 ± 3)%. CGA was quickly released when the mats were immersed in several food simulants, achieving equilibrium in less than 30 min for both materials. ABTS scavenging activity did not show significant differences (p > 0.05) regardless of the crosslinker, but DPPH activity was significantly higher (p < 0.05) in those samples crosslinked with CA. Physico-chemical properties of the developed materials were studied by FTIR, DSC, and TGA tests. Results demonstrate the release kinetics and antioxidant activity of electrospinning-fabricated water-resistant FG nanofibers.2023-12-29T00:00:00ZElevated Lead, Nickel, and Bismuth Levels in the Peritoneal Fluid of a Peritoneal Endometriosis Patient without Toxic Habits or Occupational Exposure following a Vegetarian Diet
http://hdl.handle.net/10045/139242
Título: Elevated Lead, Nickel, and Bismuth Levels in the Peritoneal Fluid of a Peritoneal Endometriosis Patient without Toxic Habits or Occupational Exposure following a Vegetarian Diet
Autor/es: López-Botella, Andrea; Gómez-Torres, María José; Sánchez, Raquel; Todolí Torró, José Luis; Velasco-Ruiz, Irene; Acién, Maribel
Resumen: Potentially toxic elements (PTEs), found as environmental contaminants, have been related to endometriosis disease. In this context, the peritoneal fluid (PF) matrix has been poorly studied despite its importance. PF is the environment in which endometriotic lesions reside and communicate with surrounding tissues including tissues and nerve cells. In this work, our investigation group reports the special case of a peritoneal endometriosis patient presenting elevated lead, nickel, and bismuth levels in PF. This patient reported following a vegetarian diet and no toxic habits or occupational exposure. In conclusion, the elevated levels of PTEs found may result from a vegetarian diet or an unidentified environmental exposure source. This report provides new insights regarding the possible etiology of endometriosis disease and potential biomarkers for its diagnosis in early stages, although additional research is needed.2023-12-10T00:00:00ZDevelopment of open-pore polymer and ceramic foams/Guefoams with tunable fluid-dynamic properties: Application in highly efficient water bacteria removal
http://hdl.handle.net/10045/138047
Título: Development of open-pore polymer and ceramic foams/Guefoams with tunable fluid-dynamic properties: Application in highly efficient water bacteria removal
Autor/es: Guidoum, Maroua; Verdú Molina, Noelia; Todolí Torró, José Luis; Maiorano Lauría, Lucila Paola; Molina Jordá, José Miguel
Resumen: The usual replication method for preparing open-pore metal foams using NaCl as a template cannot be successfully applied to the fabrication of foams using either water-based ceramic slurries in which NaCl can be dissolved during processing, or liquid polymers that wet NaCl and leave no interconnecting windows between pores. In this work, we propose to modify the replication process by including a second template, paraffin, which is deposited over the NaCl and serves a dual purpose: (i) it acts as a barrier to dissolution of the NaCl with the matrix precursor, and (ii) it creates size-controllable binding collars between the particles that ensure the formation of interconnecting windows in the foam. The usefulness of the process described here is illustrated by the fabrication of two types of materials: low porosity epoxy and cement matrix foams and Guefoams. As proof of concept, epoxy-based Guefoams were developed for the removal of Escherichia coli in water using iodine-impregnated activated carbon particles as the guest phase. The results indicate that the Guefoams outperform conventional bactericidal particle beds in several aspects, including their ease of handling and their tunable fluid-dynamic properties that enable high bacteria annihilation efficiency.2023-10-20T00:00:00Z