Publications

Abstract Extensive research has focused on films formed by pure ionic liquids (ILs). However, growing interest in IL mixtures and their synergistic properties presents new opportunities for targeted applications and fundamental scientific investigations. This study explores the morphology of films composed of mixtures of two ILs, [C2C1im][OTf] and [C8C1im][OTf], co-deposited via physical vapor deposition (PVD)/vacuum thermal evaporation. The primary objective was understanding how varying the IL ratio influences droplet formation, surface coverage, and overall film structure. Thin-film growth was examined on glass substrates coated with indium tin oxide (ITO) and ITO/glass surfaces coated with metallic films (Au and Ag). Film morphology was characterized using optical and high-resolution scanning electron microscopy (SEM), while elemental composition was analyzed via X-ray photoelectron spectroscopy (XPS). The results show that IL mixture morphology is strongly influenced by both IL composition and substrate type. Increasing [C8C1im][OTf] content led to larger microstructures due to improved wetting, particularly on Au surfaces, resulting in nearly fully coalesced films. Metallic surfaces near ITO significantly impacted droplet behavior, with ILs exhibiting a strong affinity for metals, especially when the long-chain IL dominated the mixture. The IL-assisted crystallization of rubrene, a high-performance organic semiconductor (OSC) that typically exhibits poor crystallinity when deposited via PVD, highlights the potential of IL mixtures to enhance organic film quality. X-ray diffraction (XRD) confirmed that [C2C1im][OTf] and [C8C1im][OTf] mixtures significantly improved rubrene crystallinity, demonstrating their potential to create an optimal environment for OSC solubility and crystallization.

Abstract This work integrates Talanquer's model of the chemical knowledge space, focusing on developing an educational animation and a virtual/augmented reality object. We designed the animation concerning bimolecular nucleophilic substitution, offering a multifaceted learning approach incorporating theoretical calculations and three-dimensional molecular modeling. This method facilitates a deeper understanding of complex chemical reactions and engages students in a more immersive and interactive learning experience. The use of advanced software like Blender 3D for 3D editing and animating, as well as Gaussian for generating accurate structures and electronic configurations, along with a well-thought-out pedagogical framework, allows for a higher level of abstraction in depicting how molecules interact. Our approach enhances the quality of the lessons and helps students gain a better understanding of chemistry's conceptual and practical aspects. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2025.

Abstract This study investigates spatial distribution and chemical elemental composition screening in soils in Rome (Italy) using X-ray fluorescence analysis. Fifty-nine soil samples were collected from various locations within the urban areas of the Rome municipality and were analyzed for 19 elements. Multivariate statistical techniques, including nonlinear mapping, principal component analysis, and hierarchical cluster analysis, were employed to identify clusters of similar soil samples and their spatial distribution and to try to obtain environmental quality information. The soil sample clusters result from natural geological processes and anthropogenic activities on soil contamination patterns. Spatial clustering using the k-means algorithm further identified six distinct clusters, each with specific geographical distributions and elemental characteristics. Hence, the findings underscore the importance of targeted soil assessments to ensure the sustainable use of land resources in urban areas.

Abstract This work aims to conduct a Life Cycle Assessment (LCA) of seamless leggings produced by a Portuguese textile company, following a “cradle-to-gate” approach. This includes all life cycle stages from raw material production to the packaging of the seamless leggings, ready to leave the company gate. Primary data for the foreground processes were obtained from the actual industrial practices of the Portuguese company, complemented by data from the ecoinvent V3.5 life cycle inventory database and literature sources, primarily for the background processes. The ReCiPe 2016 Midpoint (E) V1.02 methodology was employed to evaluate potential environmental impacts, using the SimaPro V8.5.2 LCA software. Results indicate that the production and spinning of fibers have the highest environmental impacts, mainly due to their high energy consumption. Dyeing operations are more impactful than confection operations, particularly contributing to water use and freshwater ecotoxicity. Therefore, efforts to reduce overall environmental impacts should initially focus on these life cycle stages. Switching the electricity source from the national grid mix to entirely photovoltaic energy resulted in a significant reduction in several environmental impact categories, including a 30% reduction in global warming potential. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2025.

Abstract Introduction: Quorum sensing (QS) is a bacterial communication mechanism that regulates gene expression, playing a crucial role in various physiological processes. Interfering with this signalling pathway is a promising strategy to control bacterial pathogenicity and virulence. Objectives: This study evaluated the potential of two cinnamic acid derivatives, ferulic and sinapic acids, to inhibit the las and pqs systems in Pseudomonas aeruginosa. Their effects on biofilm architecture, virulence factor production and bacterial motility were also investigated. Methods: Bioreporter strains and bioluminescence-based assays were used to evaluate the modulation of QS-activity by cinnamic acid-type phenolic acids. In addition, in silico docking analysis was performed to validate the binding interactions of the cinnamic acid derivatives with QS-receptors. The biofilm architecture was analysed by optical coherence tomography, and virulence factors production (pyoverdine, pyocyanin, total proteases, lipases, gelatinases and siderophores) and motility were measured by absorbance measurement and plate agar method. Results: Ferulic and sinapic acids at 1000 µg mL−1 inhibited the las and pqs systems by 90 % and 80 %, respectively. The N-3-oxododecanoyl-homoserine lactone production was reduced by 70 % (6.25 µg mL-¹). In silico analysis demonstrated that cinnamic acid derivatives exhibited comparable interactions and higher docking scores than reference ligands and inhibitors. Biofilm thickness decreased from 96 µm to 11 µm, and virulence factors and swarming motility were significantly impaired. The comparable anti-QS activity of cinnamic acid derivatives suggests that the additional methoxy group in sinapic acid does not directly contribute to its anti-QS effect. Conclusion: Ferulic and sinapic acids compromised the biofilm architecture and virulence of P. aeruginosa through QS inhibition. © 2025

Abstract Aim This study investigates the mechanisms of action of a promising series of previously synthesized quaternary ammonium (QASs) and phosphonium (QPSs) salts, which have shown potent activity against Staphylococcus aureus, including methicillin-resistant strains (MRSA).Methods and results The effects of QASs and QPSs on S. aureus surface charge, total surface hydrophobicity, intracellular potassium release, membrane integrity, and ultrastructure were examined. QASs and QPSs significantly altered bacterial surface properties by reducing negative surface charge, disrupting membrane integrity, and inducing potassium leakage and propidium iodide uptake. Furthermore, S. aureus became less hydrophilic due to changes in surface hydrophobicity. Transmission electron microscopy revealed cytoplasmic leakage and the presence of electron-dense extracellular material around damaged bacterial cells upon exposure to high concentrations of these salts.Conclusions The antimicrobial activity of QASs and QPSs is driven by their ability to alter bacterial surface properties, destabilizing and disrupting membranes.

Abstract Herein we report a visible-light-active photocatalytic nanocomposite (NC50:50) prepared from carbon dots (CDs) and TiO2 nanoparticles, which was applied to the photodegradation of organic dyes in water. The CDs incorporated corn stover, a major agricultural waste, and were prepared via hydrothermal treatment. Using a visible- light irradiation source and the dye methylene blue as a representative of the organic dyes class, we observed that a 374 % enhancement of the catalytic performance was achieved by adding CDs relative to bare TiO2. This was possible due to increased visible-light absorption and better photonic efficiency. Tests using reactive species scavengers indicated that three active species (superoxide anion, hydroxyl radicals, and electrons) were responsible for the photodegradation process, differing from bare TiO2 in which only the hydroxyl radical has a relevant role. Photocatalytic degradation was also observed toward Rhodamine B, Orange II and Methyl Orange. Finally, we performed a life cycle assessment (LCA) study to assess and analyse the associated environmental impacts of NC50:50 compared with other alternatives, which revealed that NC50:50 is the alternative resulting in the least environmental impacts. In summary, NC50:50 could, under visible-light irradiation, efficiently remove different organic dyes while incorporating organic waste materials and reducing the impacts associated with their use. We expect that this study provides a base for a more environmentally sustainable design of visible- light-active photocatalysts via waste upcycling.

Abstract This study investigates the structural and transport properties of SDS, CTAB, and SB3-12 micelles in three deep eutectic solvents (DESs), Ethaline, Glyceline, and Reline, using molecular dynamics (MD) simulations. The influence of solvent composition on micelle morphology, interactions, and dynamics was explored, revealing key differences driven by the DES environment. Structural analyses, including eccentricity and radius of gyration, demonstrated that micelle shape and compactness vary significantly depending on the solvent. In Ethaline and Reline, larger micelles showed significant deviations from spherical shapes, while micelles in Glyceline became more spherical and compact, particularly those formed by SB3-12. Radial distribution functions highlighted different levels of micelle-solvent interactions, with SDS showing strong interactions with HBD components and SB3-12 exhibiting prominent self-interaction. According to hydrogen bonding analysis, micelles slightly disrupt the DES hydrogen bond network, with SB3-12 establishing the most significant hydrogen bond connections. The transport property analysis revealed that larger micelles have lower diffusion coefficients, whereas smaller micelles enhance DESs' component mobility. These findings advance the understanding of micelle behavior in DESs and also help in the optimization of DES-surfactant systems for applications such as electrodeposition, nanomaterial templating, and drug delivery. Future research will focus on surfactant interactions with surfaces to further improve these applications.