Publications

Abstract The formation and stabilization of silver nanoparticles (AgNPs) in thin films of ionic liquids (ILs) based on long-chain alkylimidazolium cations are demonstrated in this work. IL films were prepared by vacuum thermal evaporation using the Knudsen effusion method onto ITO/glass substrates, leading to the formation of micro- and nanosized structures distributed across the surface. The investigated ILs were symmetrical dialkylimidazolium-based systems: [C7C7im][NTf2], [C8C8im][NTf2], and [C10C10im][NTf2]. Increasing the alkyl side-chain length of the imidazolium cation resulted in larger droplet domains. AgNPs were subsequently deposited onto the IL films by sputtering. The formation of AgNPs was confirmed by scanning electron microscopy (SEM), ultraviolet (UV)-visible spectroscopy, and X-ray photoelectron spectroscopy (XPS). The results show that increasing the alkyl side-chain length promotes more effective confinement and stabilization of AgNPs, leading to improved nanoparticle formation and a narrower size distribution. The temporal stability of the Ag-containing IL films was evaluated under both air exposure and inert argon storage, revealing a strong influence of the surrounding atmosphere on nanoparticle evolution. Among the ILs studied, [C10C10im][NTf2] exhibited the most favorable behavior for AgNP formation and stabilization, providing a more stable and homogeneous nanoparticle distribution over time.

Abstract [No abstract available]

Abstract Wastewater-based epidemiology (WBE) has emerged as a powerful approach for population-level monitoring of chemical exposure, health status, and disease transmission by analysing wastewater. Although chromatographic and molecular techniques remain the gold standard in WBE, their high cost, infrastructural demands, and limited suitability for decentralized and real-time monitoring motivate the development of complementary sensing technologies. In this context, optical (bio)sensors, particularly fluorescence-based platforms, have attracted increasing attention due to their high sensitivity, rapid response, and potential for on-site monitoring. This review discusses recent advances in fluorescent optical (bio)sensors for WBE, with a particular focus on carbon dots (CDs), including waste- and biomass-derived CDs produced via green synthesis as well as CDs obtained from commercial chemicals. The applicability of CD-based sensors to wastewater-relevant analytes is evaluated, highlighting current achievements, as well as existing limitations and challenges related to real-sample validation and the translation of these platforms into robust, field-deployable systems for their implementation in sustainable wastewater monitoring and public health surveillance.

Abstract <jats:p>Persistent organic pollutants accumulate in urban soils, yet information on the occurrence, spatial variability and human health implications of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (dl-PCBs) remains limited, particularly in Portugal. Surface soils were collected from six urban and peri-urban green spaces across the Porto Metropolitan Area, encompassing contrasting land-use histories and anthropogenic settings. Seventeen sampling locations were analysed for the 17 WHO-priority PCDD/F congeners and the 12 dioxin-like PCB congeners. The total number of 2005 toxic equivalents (TEQs) was determined, and screening-level human health risks were evaluated for adults considering incidental soil ingestion, dermal contact and inhalation of resuspended soil particles. PCDD/Fs and dl-PCBs were detected at all sampling locations, with total TEQ concentrations ranging from 1.91 to 330.9 ng TEQ kg⁻¹ dry weight. PCDD/Fs accounted for most of the overall toxicity. The majority of the samples under analysis can be considered representative of the urban background level in Porto, at 2.51 ± 0.54 ng TEQ kg⁻¹ dw. TEQ concentrations at most sites were consistent with diffuse urban background levels reported internationally, whereas one informal urban allotment constituted a distinct contamination hotspot. This spatial pattern was reflected in the risk assessment. Non-carcinogenic and carcinogenic risks remained below widely accepted screening thresholds at all locations except the hotspot, where children exhibited a hazard index (HI) of 1.50 and an incremental lifetime cancer risk (ILCR) of 1.17 × 10⁻⁵. Incidental soil ingestion was the predominant exposure pathway; dermal contact contributed modestly, and inhalation contributed negligibly. Sensitivity analysis demonstrated that these conclusions were robust to alternative assumptions about soil ingestion. These findings suggest that historical land use is a major determinant of site-specific PCDD/F and dl-PCB contamination and associated human health risks in urban green spaces. Incorporating land-use history into urban soil assessments could improve contamination hotspot identification and strengthen environmental monitoring and risk management strategies.</jats:p>

Abstract The high costs of equipment and maintenance for Chemistry laboratories are a barrier to quality education in this science. However, the emergence of user-friendly and low-cost technological tools helps to mitigate this problem. This paper presents a STEM proposal for exploring distillation collaboratively in a remote laboratory with live data transmission and sharing online. The approach was analyzed by four teachers from Mozambique who, in that context, highlighted the positive potential for knowledge exchange between schools and cultures and the negative lack of technological means in schools for its implementation. They recognize great potential for implementation in higher education, as institutions have better resources. Thus, richer learning experiences can be promoted for all participants.

Abstract Student-centred learning requires a variety of approaches, such as inquiry-based learning and the tackling of authentic and problem-based learning activities, to make the teaching and learning process more meaningful and to encourage students to participate more actively in class. The inquiry approach enables students to investigate solutions to real problems, awakening their need to ask questions, design and conduct research, collect and analyse data, interpret results and present them in a structured way. This study investigates the influence of an inquiry-based science education (IBSE) module on the development of oral and written communication skills among 10th grade students. The study is set in a secondary school context and focuses on a problem-based learning approach centred around gases and dispersions. A total of 111 students participated in this one-group post-assessment qualitative study, where evaluation rubrics were applied to assess students' written and oral communication, focusing on correctness, clarity and mastery of scientific language. The results showed that the majority of students performed well in both written and oral tasks, demonstrating improved scientific communication skills. This suggests that IBSE, particularly in the context of secondary education, can be an effective approach to fostering students' abilities to communicate scientific concepts. The study has implications for enhancing pedagogical practices and encourages further research on the long-term effects of IBSE on student learning.

Abstract An acid-base titrator connected to the Internet was developed for conducting remote investigative experiments. The experiment was broadcasted in a high school senior classroom, with the presence of a facilitating teacher. The activity required students to determine the indicator present in the solution. To carry out the activity, students added acid or base to sweep the pH range from 0 to 14 and noted the corresponding coloration to the pH through video analysis. The results obtained were very satisfactory, both in the identification of the indicator and in the acceptance and engagement of the students in the activity.

Abstract Educators cannot overlook the affect's potential for students’ educational success. In this study, affective analogies are proposed as a didactic resource to foster students’ affect for chemistry learning and positive attitudes towards the physics-chemistry subject. To examine the influence of the affective analogies on it, we grouped contents of this subject into three modules (Kinetic-molecular theory; Quantum model of the atom; Chemical elements and their isotopes) and developed analogies between chemistry and music for each (affective analogies), which were then compared to homologous undifferentiated analogies (familiar analogues without affective qualities in addition) and teaching strategies without analogies. An explanatory mixed-method design was used. Data were collected through questionnaires and interviews, with a convenience sample of 147 students attending the 7th grade of a middle school music course. The results show that the affective dimension of analogies promotes positive affect for learning at much higher levels than the familiar dimension. We proposed a mechanism through which this occurs. However, if analogies are familiar, it seems that their positive affective dimension is not as important for students’ learning levels. More than interesting, analogies should perhaps be non-aversive. As for attitudes towards physics-chemistry, teaching with affective analogies is the most beneficial strategy. This results from students’ perception that this teaching approach promoted positive affect for the study of physics-chemistry, compared to undifferentiated analogies and without analogies. Furthermore, it favoured learning and achievement in physics-chemistry, compared to the absence of analogies, because without analogies it is more difficult to understand abstract or difficult concepts. © 2025 Fırtına Akademi A.Ş. All rights reserved. This article published by TUSED is released under the CC BY-NC-ND license.

Abstract New psychoactive substances (NPS) are designed to evade legal regulation while mimicking the effects of classic illicit drugs such as 3,4-methylenedioxymethamphetamine (MDMA). This category includes phenethylamine derivatives, such as the psychedelic 2C and NBOMe drugs. Given the lack of data regarding the toxicological profile of these substances, the goal of this study was to evaluate the neurotoxicity of 2C-I and 25I-NBOMe and explore their neurotoxic pathways. Lower EC50 values, in both NR uptake and MTT reduction assays in differentiated SH-SY5Y cells and primary rat cortical cultures, revealed that 25I-NBOMe is significantly more cytotoxic than 2C-I, likely due to its higher lipophilicity. Both drugs triggered severe mitochondrial dysfunction, characterized by decreased intracellular ATP levels and mitochondrial membrane depolarization, although no significant changes in intracellular ROS/RNS levels were observed. Additionally, 25I-NBOMe increased the intracellular Ca2* levels. Apoptosis was an observed mechanism of cell death for both drugs, as demonstrated by a significant increase in the number of cells undergoing early apoptosis (AnV+/PI-) and late apoptosis/necrosis (AnV+/PI+). However, only 2C-I induced autophagy and strongly triggered caspase-3 activation. This suggests that 2C-I induces caspase-3-dependent apoptosis, whereas 25I-NBOMe may also induce apoptosis through a caspase-3-independent pathway, possibly involving increased intracellular Ca2* levels and direct mitochondrial damage. These findings underscore the complex interplay between mitochondrial dysfunction, calcium dysregulation, and cell death pathways, highlighting the central role of mitochondria in the cytotoxicity of 2C-I and 25INBOMe.