IQ - Artigos publicados em periódicos

URI Permanente para esta coleçãohttp://200.137.215.59//handle/ri/1299

Navegar

Agora exibindo 1 - 20 de 1283

Experimentação acessível: a design science na prototipagem de tecnologia assistiva para alunos com deficiência visual
(2025) Benite, Claudio Roberto Machado; Rodovalho, Florisbelo Magalhães; França, Fernanda Araújo; Benite, Anna Maria Canavarro
Pedagogias críticas e a interseccionalidade na formação docente em ciências/química
(2025) Faustino, Gustavo Augusto Assis; Alves, Camilla Ferreira; Nascimento, Keythy Ravena Batista; Santos, Itallo Junior Chaves dos; Vargas, Regina Nobre; Camargo, Marysson Jonas Rodrigues; Benite, Anna Maria Canavarro
In Brazil, the struggle of women for their rights, such as voting, freedom, autonomy, participation in the labor market, public life, and education, has been arduous and constant. Black women occupy a unique position in society, marked by multiple forms of oppression: gender, race, and class. Motivated by the desire to combat the disparity affecting women around the world, Black human rights activists have made significant advances in recent decades, ensuring greater attention to the issue of women's and gender rights abuses. With elements of participatory research, using Content Analysis (CA), our goal in this work was to investigate and describe the teacher training process in science, focusing on the development of a lesson conceived by course participants as part of the course evaluation around intersectionality and anti-racist education. Our results show that using Information and Communication Technologies (ICTs) with science teachers can be a way to diversify pedagogical strategies in educational practices. Additionally, the results highlighted the overlapping discriminations that shape Black women’s experiences, making it necessary to recognize the diversity and multiple dimensions of female identities. Finally, the analogies between intersectionality and their fields of study, resulting in words that express the complexity of the concept, encouraged students to reflect on the multiple dimensions present in the debate on this theme.
Miniaturized sample preparation strategies for the determination of N-nitrosamines in pharmaceutical products: A comprehensive review
(2025-12) Batista Junior, Almir Custodio; Rocha, Yuri Arrates; Chaves, Andréa Rodrigues
N-Nitrosamines (NAs) are classified as potent mutagenic impurities, raising substantial concerns due to their presence in various consumer products, including pharmaceuticals products. The detection of NAs in valsartan-containing medicines in 2018 led regulatory agencies to establish strict guidelines for permissible levels in drug formulations. The standard-gold analytical techniques for NAs determination have been chromatographic techniques (liquid and gas chromatography) coupled with mass spectrometry system, which present higher sensibility and accuracy for target NAs. However, accurate determination of NAs in medicines remains challenging due to their trace-level concentrations and susceptibility to matrix effects, carryover, and contamination of the analytical instrumentation, emphasizing the need for robust sample preparation strategies. Traditional sample preparation methods, although effective, often involve high consumption of solvents, samples, and extraction phases, along with substantial waste generation. In response, miniaturized sample preparation techniques have emerged as sustainable alternatives, offering reduced solvent usage, minimal sample requirements, and lower energy consumption, all while maintaining analytical performance. These green approaches not only align with sustainable analytical practices but also enhance efficiency and environmental compliance in pharmaceutical analysis. This review provides a comprehensive overview of recent advancements in miniaturized sample preparation strategies for the determination of NAs in pharmaceutical products, highlighting their analytical merits and potential for regulatory adoption.
Educação para as relações étnico-raciais (ERER) na formação docente em química: abordando a temática corante azul
(2025) Silva, Eliete Lucia; Camargo, Marysson Jonas Rodrigues; Benite, Anna Maria Canavarro
This study aimed to present and reflect upon an experience of incorporating the themes encompassed by Law 10.639/03—which mandates the teaching of African and Afro-Brazilian history and culture in basic education—into a teacher training program for Chemistry educators at a state university in the Central-West region of Brazil. More specifically, the focus was on the extraction of blue dye from Indigofera tinctoria, considered as a form of biotechnology originating from western Sudan (Mali). A pedagogical intervention (PI) was developed within a specific mandatory course in the program, targeting students in their seventh semester. The intervention was audio-recorded and subsequently transcribed for later analysis. The investigation was characterized as an action research project, and the data were examined through Conversation Analysis (CA). Our results revealed contradictions in the development of the PI related to discussions on racism; we identified epistemic shifts within the proposal, and we found it possible to discuss chemical concepts alongside topics related to African heritage and African history.
Metabolomic changes in rice (Oryza sativa L.) subjected to herbicide application through HPLC-HRMS and chemometrics approaches
(2025) Batista Júnior, Almir Custódio; Roque, Jussara Valente; Lima, Nerilson Marques; Soares, Daniel de Almeida; Silva, Mellissa Ananias Soler da; Chaves, Andréa Rodrigues
This study evaluated rice samples (Oryza sativa L.)─rice husk, husk and grain, polished grain, and unpolished grain─exposed to imazapyr, imazapic, and clomazone using high-performance liquid chromatography coupled to high-resolution mass spectrometry (HPLC-HRMS) and chemometric analysis. Partial least squares discriminant analysis (PLS-DA) was applied to HPLC-HRMS data, successfully distinguishing between herbicide-treated and control samples. Additionally, variable importance in projection (VIP) scores were then computed to identify key metabolites contributing to class differentiation, with higher scores indicating the most influential m/z values. These findings revealed metabolites affected by herbicide exposure and variations in the rice matrix. Furthermore, the most relevant m/z values were putatively annotated using spectral libraries, enabling the assessment of herbicide-induced metabolomic changes in rice. Herbicide treatment resulted in reduced free sugar levels across all rice matrices and led to a decrease in flavonoid content in the husk, indicating a potential suppressive effect on flavonoid accumulation. In addition, the herbicide treatment markedly disrupted the phenylpropanoid biosynthesis pathway. Overall, the combination of HPLC-HRMS analysis with multivariate approaches proved effective in detecting significant variations in the rice metabolome cultivated under herbicide application, paving the way for understanding the effects of herbicides in crop cultivation.
Assessing antiparasitic compounds persistence in cattle hair by DART-MS
(2025) Batista Júnior, Almir Custódio; Maciel, Lanaia Ítala Louzeiro; Rocha, Yuri Arrates; Souza, Gabriela Guimarães; Vaz, Boniek Gontijo; Lopes, Welber Daniel Zanetti; Botelho, Ana Flávia Machado; Chalom, Marc Yves; Chaves, Andréa Rodrigues
This study introduces an alternative strategy for evaluating antiparasitic persistence compounds in cattle hair by Direct Analysis in Real Time Mass Spectrometry (DART-MS). The developed DART-MS method aimed to determine fenthion, chlorpyrifos, and cypermethrin in cattle hair samples. DART-MS analyses were performed in positive ion mode, and parameters related to the DART source were evaluated. The analytical performance demonstrated the efficiency of the optimized DART-MS method for fenthion, chlorpyrifos, and cypermethrin quantification in the evaluated samples, meeting criteria for precision, accuracy and limits of detection. Overall, the DART-MS method provided a fast and efficient analysis for determination of antiparasitic agents in cattle hair, which contributes to the evaluation of drug administration protocols and dosage intervals, and aids the safety and advancement of the livestock sector.
O ensino de Botânica em contexto bilíngue Português-Libras a partir da Teoria Histórico-Cultural
(2025) Rodrigues, Gustavo Fernandes; Pereira, Lidiane de Lemos Soares; Benite, Anna Maria Canavarro
Este artículo, basado en la Teoría Histórico-Cultural, investiga la apropiación conceptual de estudiantes sordos en un entorno bilingüe, con un enfoque en la enseñanza de Botánica. Para ello, se elaboró una secuencia didáctica compuesta por cuatro intervenciones pedagógicas, aplicadas en 2023. La investigación utilizó cuestionarios, actividades visuales y grabaciones en video como instrumentos de recolección de datos, analizados mediante el análisis de la conversación. Los resultados indican que las estrategias pedagógicas visuales potencian el aprendizaje y desarrollo de los estudiantes sordos, ya que actúan como signos mediadores en el proceso de construcción del conocimiento. La experimentación, al permitir la interacción social y la observación de fenómenos naturales, favorece la apropiación de conceptos científicos. Sin embargo, la investigación también señala la existencia de barreras lingüísticas y una escasa estimulación del lenguaje, factores que dificultan la adquisición de conceptos espontáneos y comprometen la elaboración de conocimientos científicos.
Interaction of microplastics with emerging organic pollutants: a study on atrazine adsorption and phytotoxicity
(2025) Souza, Luan Gabriel Xavier de; Teran, Francisco Javier Cuba; Cuba, Renata Medici Frayne; Chaves, Andréa Rodrigues; Silva, Kellen Cristina da
The adsorption of atrazine (ATZ) onto pristine and aged polyethylene microplastics (MPs) was investigated in distilled water (DW) and hydroponic nutrient-enriched water (EW) to evaluate its phytotoxic effects on Lactuca sativa germination. Aged microplastics (AMPs) exhibited higher ATZ adsorption in both conditions: 0.646 mg/g (14.49%) in DW and 0.742 mg/g (15.87%) in EW, compared to 0.405 mg/g (9.08%) and 0.504 mg/g (10.78%) for pristine microplastics (PMPs), respectively. This increase was attributed to photodegradation-induced surface modifications on MP, including increased roughness and the formation of oxygenated functional groups. The phytotoxicity assays showed that ATZ adsorbed onto AMPs inhibited seed germination more severely, with a maximum inhibition of 34% at 2 mg/L, evidencing that microplastic aging enhances ATZ adsorption and increases toxicity risks in aquatic environments, particularly under eutrophic conditions. The combined presence of MP and ATZ resulted in greater toxicity, attributed to a synergistic effect, as observed in dry and wet mass inhibition. These findings indicate that pollutant interactions amplify negative impacts on plant development. Furthermore, ATZ primarily affects root growth through direct physical contact with MP rather than via desorption into water.
Plantas medicinais e a produção de tecnologias negrorreferenciadas na formação docente em Ciências/Química
(2025) Faustino, Gustavo Augusto Assis; Bernardes, Clarissa Alves Carneiro; Vargas, Regina Nobre; Silva, Thatianny Alves de Lima; Ruela, Brunno André; Costa, Fernando Rocha da; Camargo, Marysson Jonas Rodrigues; Benite, Anna Maria Canavarro
The curriculum can reflect and reproduce different systems of oppression. Thus, there is an urgent need to address themes related to ethnic-racial relations in the initial and continuing education of teachers, through an epistemic shift grounded in interculturality. Employing elements of participatory research, our objective in this study was to analyze and characterize the formative process of the postgraduate students in the development of a seminar as an evaluative stage of the discipline, concerning traditional knowledge of medicinal plants. Our results demonstrate the necessity of overcoming the limitations imposed by a Eurocentric view of reality, mainly regarding the importance of discussing African and Afro-diasporic knowledge and technologies in teacher education. In addition, we recognize the significance of discussing the production of Blackreferenced Science and Technology. Thus, our results also demonstrate the possibility of working with Science teachers on theoretical-methodological strategies that enable epistemic displacement. Lastly, our results indicate that formative processes like this seem to have fulfilled their social function by instigating these Science/Chemistry teachers to seek, beyond the rigid model of their training, possibilities of debating Black-referenced technologies into school curricula.
Solar-driven sustainable process combined with heterogeneous photocatalysis (TiO₂): degradation of penicillin and indigo carmine blue dye
(2025) Alves Filho, Carlos Teixeira; Almeida, Maria Carolina de; Batista Júnior, Almir Custódio; Chaves, Andréa Rodrigues; Sá, Fernando Pereira de; Oliveira, Tatianne Ferreira de
Remediation of Contaminants of Emerging Concern (CECs) in wastewater is a global demand that cannot be ignored. In this study, heterogeneous photocatalysis using titanium dioxide (TiO2) coupled with solar radiation was applied to catalytically degrade the food indigo carmine blue dye and the antibiotic penicillin through the generation of reactive oxygen species as degradation agents. Advanced Oxidation Processes (AOPs) have been widely used in wastewater treatment due to the ability of heterogeneous catalysts to promote fast and efficient degradation rates of CECs –primarily through the formation of reactive oxygen species, such as hydroxyl radicals and others. The proposed treatment was carried out using heterogeneous photocatalysis with TiO2(Degussa P25, 30 mg/L) under solar radiation (during peak UV exposure hours), with pH variations of 4, 7, and 10. Degradation kinetics were monitored for 120 minutes in a closed recirculation system with synthetic wastewater driven by an oxygen injection pump. The solutions with studied CECs made with analytical grade (each at 30 mg/L), analyzed separately. The coupling of treatments enhanced the treatment,improving degradation efficiency while reducing costs. Thus, this innovative approach -solar-driven heterogeneous photo catalysis shows promising potential for the efficient degradation of CECs from the food and pharmaceutical industries.
Integrating FT-ICR MS and machine learning to forecast acid content across boiling cuts
(2025) Roque, Jussara Valente; Cardoso, Wilson Junior; Aguiar, Deborah Victória Alves de; Santos, Gabriel Franco dos; Gomes, Alexandre de Oliveira; Medeiros Júnior, Íris; Lima, Gesiane da Silva; Vaz, Boniek Gontijo
In this study, we introduce a pioneering approach that leverages advanced machine learning and ultrahigh-resolution Fourier transform ion cyclotron mass spectrometry (FT-ICR MS) data to predict the distribution of the total acid number (TAN) in true boiling point (TBP) distillation cuts from crude oil. By employing partial least-squares (PLS) regression and ordered predictor selection (OPS), we achieved robust predictive models with high accuracy, evidenced by low root-mean-square error of calibration (RMSEC) and strong correlation coefficients (Rc). Our analysis of 36 diverse crude oil samples revealed significant variations in chemical composition, with nitrogen- and oxygen-containing compounds playing key roles in influencing TAN values. Through the use of volcano plots, we identified critical molecular classes that drive changes in TAN. The predictive models demonstrated remarkable consistency between predicted and actual TAN values, particularly in samples with a higher TAN, further validating their reliability. Significantly, our method overcomes the limitations of traditional ASTM testing by requiring smaller sample volumes while still providing accurate TAN predictions. This novel approach offers a powerful new tool for the molecular characterization and behavioral forecasting of complex mixtures, enabling a more efficient pathway for sample analysis when resources are limited.
A bottled high-sulfur fuel oil stranded with the mysterious oil spill on the brazilian coast in early 2022: geochemical correlation and ocean dumping evidence
(2025) Azevedo, Rufino Neto Andrade de; Nascimento, Adriana Pereira; Pereira, Vinícius Barreto; Franco, Danielle Mitze Muller; Nelson, Robert K.; Vaz, Boniek Gontijo; Azevedo, Débora de Almeida; Nascimento, Ronaldo Ferreira do; Reddy, Christopher M.; Cavalcante, Rivelino Martins
This study conducted a comprehensive forensic geochemical and chemical assessment of bottled oil labeled with a foreign marine bunker company stranded on a Ceará beach, Northeast Brazil, in January 2022, and compared it to the mysterious oil spill that affected ∼342 km of the Ceará coast at that time. The saturated and aromatic composition was assessed by conventional gas chromatography (GC-FID and GC-MS) and comprehensive two-dimensional gas chromatography (GC × GC-FID). In addition, the bottled oil was also assessed by Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS), CHNS elemental analyses, and microscopic imaging. The bimodal unresolved complex mixture (UCM) in the GC-FID chromatogram; the considerable abundance of anthracene, 2-methylanthracene, and other polycyclic aromatic hydrocarbons (PAHs) with four, five, and six rings; and the high abundance in carbon 40 observed for the N1 class for the bottled oil are consistent with heavy fuel oil (HFO), probably an IFO 380. It has a high sulfur content (2.5%) outside the 2020 International Maritime Organization (IMO) specifications (%S < 0.5) unless the vessels are equipped with exhaust gas cleaning systems (EGCS or scrubbers). The fuel oil also has a high amount of catalytic fines, rich in Al and Si, which are known to damage marine engines and pose a potential threat to the environment. Resistant biomarkers (e.g., terpanes, steranes, C30 tetracyclic polyprenoids, and triaromatic steranes) and the GC-FID profile showed that this fuel oil geochemically correlates with the early 2022 oil spill, disclosing the spilled oil source from fuel dumping by an international tanker on the South Atlantic Ocean route. Fingerprint dissimilarities of the more volatile compounds indicate intense weathering or two different vessel fuel tanks. The high sulfur content and the presence of catalytic fines may explain the oil being disposed of into the sea.
Harnessing mass spectrometry for molecular analysis in energy: from fossil fuels to renewables
(2025) Lima, Nerilson Marques; Aguiar, Deborah Victória Alves de; Vaz, Boniek Gontijo
Mass spectrometry (MS) has become an indispensable tool for the detailed chemical analysis of materials used in energy production, spanning both traditional fossil fuels and modern renewable alternatives. This review explores advanced ionization sources and ultrahigh-resolution MS technologies in analyzing energy materials such as petroleum, biomass, biofuels, and bio-oil. Highlighted ionization techniques include electrospray ionization, atmospheric pressure chemical ionization, atmospheric pressure photoionization, laser desorption/ionization, and matrix-assisted laser desorption/ionization, all crucial for qualitative and quantitative assessments, as well as ultrahigh-resolution Fourier transform ion cyclotron resonance and Orbitrap mass analyzers. This review underscores the remarkable compositional detail achievable with state-of-the-art MS systems, providing molecular-level insights vital for advancing energy sectors. Introducing the concept of harvesting MS, we illustrate how these techniques can overcome challenges and optimize energy operations. Through case studies, this article highlights how these insights enhance energy production efficiency and sustainability, paving the way for future innovations.
Hidden carbenes: NHC-Al species at the Al2O3–ionic liquid interface
(2025) Qadir, Muhammad Irfan; Ebersol, Camila Porto; Silva, Blendo Almeida da; Castegnaro, Marcus Vinicius; Lião, Luciano Morais; Sanches Neto, Flávio Olimpio; Oliveira, Heibbe Cristhian Benedito de; Pontes, Renato Borges; Ebeling, Gunter; Dupont, Jairton
The modification of the surface chemistry of heterogeneous catalysts/supports alters their electronic and catalytic properties, particularly through the incorporation of a monolayer of sophisticated N-heterocyclic carbenes (NHCs). However, the formation of aluminum N-heterocyclic carbene (NHC-Al) goes unrecognized or remains unidentified when imidazolium-based ionic liquids are supported on solids (SILPs). In this work, we identified the formation of NHC-Al species upon the grafting of imidazolium-based ILs onto neutral Al2O3. The optimal geometry of the imidazolium cations in these SILPs adopts a tilted orientation, exhibiting an upright binding mode, akin to self-assembled monolayers (SAMs). This configuration enables direct interaction of the electron-rich N–C–N moiety of the imidazolium cation with the Al2O3 surface, leading to the autocatalytic formation of NHC-Al species. The NHC-Al species are confirmed through solid-state 13C NMR, 13C–1H HETCOR, 27Al NMR, synchrotron XPS, XANES, and DFT calculations. This study provides unique insights into the bonding and structural geometry of ILs in SILPs, revealing features that have previously gone unobserved.
Selective carbon dioxide hydrogenation to olefin-rich hydrocarbons by Cu/FeOx nanoarchitectures under atmospheric pressure
(2025) Qadir, Muhammad Irfan; Žilková, Naděžda; Kvitek, Libor; Vajda, Stefan
The conversion of carbon dioxide into fuels and fine chemicals is a highly desirable route for mitigating flue gas emissions. However, achieving selectivity toward olefins remains challenging and typically requires high temperatures and pressures. Herein, we address this challenge using 12 nm copper nanoparticles supported on FeOx micro-rods, which promote the selective hydrogenation of CO2 to light olefins (C2–C4) under atmospheric pressure. This catalyst achieves up to 27% conversion and 52% selectivity toward C2–C4 olefins, along with the production of C2–C4 paraffins, C5+ hydrocarbons (with all C1+ products totalling to up to about 75%), and methane, while suppressing CO formation to just 1% at 340 °C. The enhanced performance of the Cu/FeOx pre-catalyst is attributed to the efficient in situ generation of iron carbides (Fe5C2) in the presence of copper nanoparticles, as confirmed by ex situ XRD analysis. Copper facilitates the reduction of FeOx to form Fe5C2, a crucial intermediate for shifting the reaction equilibrium toward higher hydrocarbons. The hydrogenation of CO2 to higher hydrocarbons proceeds through the reverse water–gas shift reaction coupled with Fischer–Tropsch synthesis.
Recent advances in TiO2-based photocatalysts for efficient water splitting to hydrogen
(2025) Muhammad Nisar, Zeban Shah; Khan, Niqab; Qadir, Muhammad Irfan; Shah, Zeban
Titanium dioxide (TiO2) has been widely used as a potential candidate for the production of green hydrogen using the artificial photosynthesis approach. However, the wide bandgap (∼3.3 eV) of anatase TiO2 makes it difficult to absorb a large fraction of the solar radiation reaching the Earth, thus providing a low photocatalytic activity. Anatase TiO2 absorbs only 4% of solar radiation, which can be improved by engineering its bandgap to enhance absorption in the visible region. In the literature, many strategies have been adopted to improve the photocatalytic activity of TiO2, such as metal and non-metal doping and heterojunctions. These techniques have shown incredible enhancement in visible light absorption and improved photocatalytic activity due to their ability to lower the bandgap of pure TiO2 semiconductors. This review highlights different techniques like doping, heterojunctions, acidic modification, creating oxygen vacancies, and temperature- and pressure-dependence, which have improved the photochemical response of TiO2 by improving charge-transfer efficiencies. Additionally, the charge-transfer mechanism and enhancement in the photochemical response of TiO2 is discussed in each portion separately.
Drone and paper-based analytical devices: a powerful combination for the colorimetric detection of tropospheric ozone
(2025) Campos, Pedro P. E.; Silva Neto, Habdias de Araujo; Duarte, Lucas da Costa; Petruci, João Flávio da Silveira; Coltro, Wendell Karlos Tomazelli
Ozone is a harmful atmospheric pollutant whose elevated concentrations (i.e., higher than 0.16 mg m–3) and prolonged exposure cause severe damage to the human respiratory system and negatively affect flora and fauna. Vertical ozone monitoring remains challenging due to the limitations of traditional sensors, which are bulky, expensive, and slow to provide results at the site of interest. To address this problem, there is a critical need for portable technologies that allow for rapid and efficient in situ detection. This study presents, for the first time, the integration of paper-based analytical devices (PADs) with a commercial drone to combine them for remote sampling and ozone colorimetric detection. The PADs were manufactured using a stencil-printing technique on chromatographic paper, with circular vinyl stencil masks (Ø = 5 mm) applied to define the detection areas on the paper. The hydrophobic barrier was created by depositing varnish resin onto the stencil/paper surface, with the masks removed after drying, resulting in PADs ready for use. As proof of concept, the paper detection zone surfaces were impregnated with potassium indigotrisulfonate (ITS) and polyethylene glycol (PEG), aiming to sample and detect gaseous ozone. The colorimetric method was performed using a desktop scanner to capture images, which were analyzed by graphical software to evaluate the resulting color intensity that varied from blue to colorless. A commercial ozone generator was used to optimize the method parameters. Parameters such as reaction time, reagent volume, and PEG concentration were optimized, resulting in a linear response range for ozone between 0.9 and 7.6 mg, with an R2 of 0.996, and a limit of detection of approximately 0.25 mg. A customized holder was fabricated by 3D printing to ensure the attachment of PADs on the aerial drone platform. The system successfully monitored tropospheric ozone levels, recording 6.8 ± 0.7 mg during the dry season and 0.9 ± 0.1 mg during wet periods, with an in-flight sampling time of just 120 s. This innovative system has great potential to advance environmental monitoring, offering a portable, low-cost solution for remote and real-time ozone detection.
Screen-printing vs additive manufacturing approaches: recent aspects and trends involving the fabrication of electrochemical sensors
(2025) Orzari, Luiz Otávio; Kalinke, Cristiane; Silva Neto, Habdias de Araujo; Rocha, Danielly Santos; Camargo, Jéssica Rocha; Coltro, Wendell Karlos Tomazelli; Janegitz, Bruno Campos
A few decades ago, the technological boom revolutionized access to information, ushering in a new era of research possibilities. Electrochemical devices have recently emerged as a key scientific advancement utilizing electrochemistry principles to detect various chemical species. These versatile electrodes find applications in diverse fields, such as healthcare diagnostics and environmental monitoring. Modern designs have given rise to innovative manufacturing protocols, including screen and additive printing methods, for creating sophisticated 2D and 3D electrochemical devices. This perspective provides a comprehensive overview of the screen-printing and additive-printing protocols for constructing electrochemical devices. It is also informed that screen-printed sensors offer cost-effectiveness and ease of fabrication, although they may pose challenges due to the use of toxic volatile inks and limited design flexibility. On the other hand, additive manufacturing, especially the fused filament fabrication (or fused deposition modeling) strategies, allows for intricate three-dimensional sensor designs and rapid prototyping of customized equipment. However, the post-treatment processes and material selection can affect production costs. Despite their unique advantages and limitations, both printing techniques show promise for various applications, driving innovation in the field toward more advanced sensor designs. Finally, these advancements pave the way for improved sensor performance and expand possibilities for academic, environmental, and industrial applications. The future is full of exciting opportunities for state-of-the-art sensor technologies that will further improve our ability to detect and determine various substances in a wide range of environments as researchers continue to explore the many possibilities of electrochemical devices.
Evaluation of amitraz and derivatives in poisoned cat fur: a new screening method via headspace/gas chromatography-mass spectrometry - case report
(2025) Prado, Laís di Paulie Taborda; Barbosa, João Marcos Gonçalves; Vicente, Monica Chacon de; Barros, Alexandre Có Mangoni; Correia, Nelcimara Mirley de Souza; Silva, Laura Linhares Peixoto; Rodrigues, Beatriz Kawamura; David, Lurian Caetano; Botelho, Ana Flávia Machado; Antoniosi Filho, Nelson Roberto
Amitraz is a toxic pesticide that causes severe poisoning in animals; however, few reports of poisoning in cats can be found. Current diagnostic techniques mostly use invasive sampling and require a long time. A new noninvasive technique presented in this report provides accurate diagnosis. Here, we report a case of a 5-year-old male Persian cat with no prior history of illness, presenting vomiting, decreased consciousness, ataxia, and prostration following topical amitraz application for flea control. When admitted to the emergency service, 0.1% of intravenous yohimbine hydrochloride solution was administered to reverse the α-2 adrenergic agonist effects caused by the pesticide. Clinical tests indicated a slight increase in the alanine transaminase (ALT). Furthermore, samples from fur were collected during hospitalization to confirm and follow up the amitraz diagnosis using headspace/gas chromatography-mass spectrometry (HS/GC-MS) analysis. The presence of amitraz in the fur was detected by HS/GC-MS through its derivative products 2,4-dimethylaniline (DMA) and 2,4-Dimethylphenylformamide (DMF). After 24 hours, the patient was released with recommendations to avoid amitraz use and a recommendation for a bath and clipping. Fast aid and antidote administration were decisive factors in the successful treatment. Fur HS/GC-MS stands out as a definitive diagnosis of amitraz poisoning using non-invasive samples.
Identification of chlorogenic acids from Moringa oleifera leaves as modulators of prion aggregation using affinity selection-mass spectrometry
(2025) Amorim, Magali Silva de; Nascimento, Manuela Amaral do; Severino, Vanessa Gisele Pasqualotto; Silva, Jerson Lima da; Vieira, Tuane Cristine Ramos Gonçalves; Moraes, Marcela Cristina de
Prion diseases are fatal neurodegenerative disorders caused by the misfolding and aggregation of the cellular prion protein (PrPC) into its pathogenic form (PrPSc), leading to progressive neurodegeneration. Currently, no effective treatments are available, highlighting the need for novel therapeutic strategies. In this study, we explored the potential of Moringa oleifera extracts as a source of bioactive compounds that could modulate prion protein aggregation. A hydroethanolic extract from M. oleifera leaves was analyzed using PrP aggregation inhibition profiling via real-time quaking-induced conversion (RT-QuIC) assays, in combination with affinity selection-mass spectrometry (AS-MS). This approach identified chlorogenic and neochlorogenic acids as potent inhibitors of prion aggregation. These compounds exhibited significant antiprion activity, with IC50 values of 64.41 ± 12.12 and 35.34 ± 7.09 μM, respectively. In addition to inhibiting the conversion of PrPC to PrPSc, both compounds could disaggregate preformed PrPSc fibrils in vitro. AS-MS proved to be a valuable tool for isolating the modulators of PrP aggregation directly from crude natural product extracts, avoiding the need for expensive and time-consuming fractionation and purification processes. Identifying chlorogenic and neochlorogenic acids highlights the therapeutic potential of natural products in combating prion diseases and other amyloidogenic disorders. Our findings suggest that these bioactive compounds could serve as promising lead compounds for developing novel treatments for prion diseases. Further in vivo studies and pharmacokinetic optimization are warranted to explore their full therapeutic potential.

Navegar

Submissões Recentes