IQ - Artigos publicados em periódicos

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

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Agora exibindo 1 - 20 de 1404

A novel paper/plastic-based hybrid strip test for rapid and multiplexed colorimetric detection of milk adulterants
(2026) Sousa, Lucas Rodrigues de; Guinati, Bárbara Guerra de Souza; Oliveira, Karoliny Almeida; Chagas, Cyro Lucas Silva; Coltro, Wendell Karlos Tomazelli
Milk adulteration remains a major concern for food safety and consumer protection, as it can compromise nutritional quality and pose health risks. This study presents a low-cost hybrid paper/plastic strip test for the simultaneous detection of seven common adulterants in cow milk: urea, hydrogen peroxide, starch, formaldehyde, antioxidants (e.g., ascorbic acid), sodium hypochlorite, and neutralizers/detergents, using a pH-based colorimetric sensing without sample pretreatment. The device was fabricated using a craft cutter and combined paper and plastic substrates, allowing multiplexed detection on a single strip. Analytical performance was optimized, yielding recovery rates between 86% and 112% for key adulterants. The test strips remained stable for up to 30 days under refrigeration (2–5 °C). In a case study of 50 milk samples, the device accurately identified adulterants with minimal interference, and results showed no significant deviation from reference methods (validated by Tukey's test). With a fabrication cost of only $0.25 per unit, the proposed platform provides a reliable, affordable, and scalable solution for routine milk quality monitoring, representing a promising tool for enhancing quality control in the dairy industry.
Exploring the role of microfluidic paper-based analytical devices in salivary diagnostics: from concept to clinical applications
(2026) Sousa, Lucas Rodrigues de; Velasco, Larissa Garcia; Vlachovsky, Sandra Gabriela; Figueredo, Federico; Cortón, Eduardo; Coltro, Wendell Karlos Tomazelli
Microfluidic paper-based analytical devices (µPADs) have evolved significantly over the last few decades, from simple colorimetric strips to multifunctional lab-on-a-chip systems. This review focuses on advances in µPAD development, with particular emphasis on their application in salivary diagnostics. It covers the fundamental aspects of these devices, including their fabrication methods, detection strategies (with emphasis on colorimetry and electrochemistry), key biomarkers under investigation, and current challenges. Saliva has emerged as a promising diagnostic fluid due to its non-invasive collection, low risk, and diverse biochemical content, including proteins, enzymes, hormones, and nucleic acids. Salivary diagnostics on µPADs are closely aligned with the WHO's ASSURED criteria, making them highly promising for primary care and resource-limited settings. While some salivary biomarkers are clinically established, many remain understudied and require more accurate screening and comparison with conventional diagnostic methods. Our review also highlights how the remaining challenges, such as biomarker variability, integration of sample pretreatment steps, and interference from biological components, are being resolved by the scientific community. In doing so, we present the state-of-the-art and ongoing advances that are essential to establish µPADs as accessible and effective tools in global public health.
From prototype to point-of-care: digital microfluidics for scalable biomedical applications
(2026) Santos, Daniel José Altenburg dos; Silva, Danyanne Kristhielly da; Velasco, Larissa Garcia; Campos, Richard Piffer Soares de; Coltro, Wendell Karlos Tomazelli
Digital microfluidics (DMF) has emerged as a powerful platform for automating and miniaturizing biomedical assays, enabling high-precision, low-volume workflows. However, its transition from research laboratory to industrial-scale manufacturing faces persistent barriers. These include the need for high actuation voltages, material degradation, lack of standardization, and the complexity of integrating diverse detection systems. This review explores and critically discusses recent advances in integrating sensors, hybrid device architectures, and programmable controllers to enhance DMF reliability, portability, and scalability. Emphasis is placed on inter-disciplinary efforts that bridge engineering, materials science, and diagnostics to address fabrication challenges, support real-world applications, and establish DMF as a viable technology for clinical diagnostics and point-of-care platforms.
Acetogenins from Annona coriacea target TNFR1-mediated cell death in head and neck cancer
(2026) Cordeiro, Gilvânia Aparecida Rabelo; Oliveira, Ana Gabriela Silva; Junqueira, João Gabriel Morais; Sousa, Lorena Raspante de; Gonçalves, Arlan da Silva; Asevedo, Estefani Alves; Ribeiro, Rodolfo Eduardo de Morais; Reis, Rui Manuel Vieira; Severino, Vanessa Gisele Pasqualotto; Thomé, Ralph Gruppi
Head and neck cancer (HNC) remains a major therapeutic challenge due to its biological heterogeneity and limited response to current treatments, highlighting the need for more effective and less toxic therapeutic strategies. Annona coriacea Mart., a plant native to the Brazilian Cerrado, is a source of bioactive acetogenins. In this study, we evaluated the antitumor effects of acetogenin-enriched fractions from A. coriacea using in vitro and in vivo models of HNC. The fractions exhibited cytotoxic activity against FaDu and HN13 cells, with IC50 values ranging from 2.42 to 8.25 μg/mL and from 1.61 to 12.57 μg/mL, respectively, while showing lower toxicity toward nontumor cells. Mechanistic analyses suggested the involvement of mitochondrial-associated apoptotic-like and necroptotic cell death processes. Molecular docking analyses indicated a possible modulatory interaction between acetogenins and tumor necrosis factor receptor 1 (TNFR1). In vivo, the selected fraction ACL3 reduced tumor growth and angiogenesis in the CAM model without inducing vascular irritation, as confirmed by the HET-CAM assay. Together, these findings demonstrate that A. coriacea acetogenin-rich fractions exhibit selective antitumor activity, induce mitochondrial-mediated and necroptosis-related cell death mechanisms, and inhibit tumor-associated angiogenesis, supporting their potential as promising candidates for further preclinical investigation in HNC.
Metabolomic profile of edible Amazonian Arecaceae fruits by FT-ICR-MS: insights into chemical, nutritional and antioxidant profiles
(2026) Lima, Gesiane da Silva; Maciel, Lanaia Ítala Louzeiro; Lenz, Tamara; Machado, Hugo Gontijo; Lima, Nerilson Marques; Simão, Jorge Luiz Souza; Severino, Vanessa Gisele Pasqualotto; Rychlik, Michael; Vaz, Boniek Gontijo; Pieczonka, Stefan Alexander
Amazonian palm fruits (Arecaceae), including açaí (Euterpe oleracea), pupunha (Bactris gasipaes), buriti (Mauritia flexuosa), bacaba (Oenocarpus bacaba), and tucuma ̃ (Astrocaryum aculeatum) are traditionally consumed for their nutritional and therapeutic properties, yet their comprehensive metabolomic characterization remains limited. Here, an integrative foodomics approach combining untargeted and targeted analyses was applied. Direct infusion FT-ICR-MS enabled the annotation of over 10,000 molecular formulas, revealing extensive chemical diversity. Van Krevelen diagrams and chemometric analyses (HCA, PCA, PLS-DA) highlighted distinct metab- olomic signatures across species. Targeted assays showed that açaí and pupunha exhibited the highest total phenolic and flavonoid contents and the strongest antioxidant activities, comparable with Trolox, while tucuma ̃ presented the highest folate content (132.64 μg/100 g DW) These findings demonstrate associations between molecular composition and functional properties. This work represents the first FT-ICR-MS-based metabolomic characterization of these fruits, expanding current knowledge and providing a robust framework for theirvalorization in food and nutraceutical applications.
Determination of monoethylene glycol in gas condensate samples by microchip micellar electrokinetic chromatography integrated with capacitively coupled contactless conductivity detection
(2026) Pereira, Mauricio Matheus Lucio; Martins, Kariolanda Cristina de Andrade Rezende; Medeiros Júnior, Iris; Couto, Bruno Charles do; Carvalho, Rogério Mesquita de; Lago, Claudimir Lucio do; Coltro, Wendell Karlos Tomazelli
This study describes the use of microchip micellar electrokinetic chromatography (MEKC) integrated with capacitively coupled contactless conductivity detection (C4D) for the determination of monoethylene glycol (MEG) in gas condensate samples. The samples were subjected to a liquid–liquid extraction step and then analyzed by chip-based MEKC-C4D. For this purpose, sodium dodecyl sulfate (SDS) was used as a surfactant at a concentration of 30 mmol L−1 added in 50 mmol L−1 phosphate (pH = 9.0). Samples were introduced into microchannels through floating injection mode by applying a voltage of 600 V during 10 s. Separations were performed under an electric field of 82 V cm−1 and monitored by C4D measurements recorded applying a 1200-kHz frequency sinusoidal wave with 20-Vpp excitation voltage. The proposed methodology employing MEKC-C4D revealed a linear behavior (r2 ≥ 0.99) in the MEG concentration range between 150–450 μmol L−1 and LOD equal to 33 μmol L−1. Three gas condensate samples were then analyzed, and the achieved MEG concentration values ranged from 173 to 213 μmol L−1 . Recovery experiments provided values between 89 and 102%. Based on the results reported in this study, MEKC-C4D devices have demonstrated to be a promising and ecological analytical tool for MEG analysis with huge potential for in-field applications.
Sustainable stencil-printed unmodified graphite–rosin electrode for electrochemical detection of ketamine in forensic samples
(2026) Campos, Jamilson Pereira; Melo, Larissa Magalhães de Almeida; Rocha, Danielly Santos; Santos, Daniel Júnior Almeida dos; Pereira, Mauricio Matheus Lucio; Santos, Wallans Torres Pio dos; Arantes, Luciano Chaves; Coltro, Wendell Karlos Tomazelli
Ketamine (KET) is a clinically used anesthetic with a high potential for abuse. Recreational and improper use of this substance pose significant health risks, including psychological, cardiovascular, neurotoxic, and dependency-related effects. However, there is currently no official and reliable method for its preliminary detection. Therefore, the development of rapid, selective, and simple analytical methods for KET detection is of great interest in both clinical and forensic contexts. In this study, we present an unprecedented application of rosin ‒ a natural, eco-friendly resin derived from Pinus species ‒ as a green binding additive in graphite-based conductive formulations for the fabrication of stencil-printed electrodes (graphite-pine rosin composite stencil electrode, GPC-SE). The GPC-SE fabrication process was optimized, and ideal conditions for reversibility and performance were established with a composition of 45% rosin, 55% graphite, and 5 mL of solvent. The resulting sensor was characterized by Raman spectroscopy, scanning electron microscopy, and electrochemical techniques. The GPC-SE combined with square-wave voltammetry exhibited wide linear range (50–500 μmol L− 1 ) in Britton-Robinson buffer solution (pH 8, 50 mmol L− 1), high sensitivity and low limits of detection (3.3 μmol L− 1) and quantification (10.1 μmol L− 1 ). The developed GPC-SE provided satisfactory reproducibility (RSDs <1.0% for Ep and <7% for Ip) and accuracy based on addition-recovery experiments on seized samples, beverages, and spiked biological samples. These findings demonstrate the applicability of the method in both forensic and clinical scenarios as rapid, reliable, and sustainable strategy for on-site identification of KET.
Metabolite profiling and in vitro assessment of skin-related pharmacological activities in Baccharis trimera (Less.) DC
(2026) Gabor, Philipp; Mesquita Júnior, Wéldion Gonçalves; Costa, Kyuri Ribeiro Romário Pereira da; Cass, Quezia Bezerra; Severino, Vanessa Gisele Pasqualotto; Severino, Richele Priscila; Makishi, Geísa Ferreira Costa; Siqueira, Gislane Florambel; Melzig, Matthias F.; Sousa, Alexander Lorena Ramos Freitas de
Ethnopharmacological relevance: Baccharis trimera (Less.) DC. (Asteraceae), commonly known as “carqueja”, is a medicinal plant traditionally used in Brazil as an herbal remedy for gastrointestinal disorders. In some regions, its aerial parts are also used to treat skin-related diseases, including wounds. Despite growing interest in discovering new cosmeceutical ingredients from traditionally used medicinal plants, knowledge of this species and its po- tential skin-related applications remains limited. Aim of the study: We investigated the aerial parts of B. trimera for their anti-inflammatory, anti-aging, and skin- whitening properties. Materials and methods: The ethanolic extract (BtE) was fractionated via liquid-liquid extraction into hexane (BtEH), dichloromethane (BtED), ethyl acetate (BtEA), and hydroalcoholic (BtEHy) fractions. Chemical der- eplication of BtE and active fractions (BtEA and BtED) was performed using liquid chromatography coupled with high-resolution mass spectrometry (LC–HRMS). Enzyme inhibitory activity against tyrosinase and elastase was evaluated spectrophotometrically. Anti-inflammatory activity was assessed in lipopolysaccharide (LPS)-stimu- lated THP-1 macrophages by quantifying TNF-α, IL-1β, and IL-6 levels using ELISA. Results: The crude extract inhibited elastase activity, while its fractions reduced cytokine production and enhanced tyrosinase inhibition. Among these, the dichloromethane fraction showed the most pronounced effects, including tyrosinase inhibition, reduced secretion of TNF-α, IL-1β and IL-6, and a significant decrease in LPS- induced LDH release. Twenty compounds, including flavonoids, hydroxycinnamic acid derivatives, diterpenes, phenylpropanoids, and fatty acids, were annotated in the active ethanolic extract and its fractions from Baccharis trimera, several of which have previously shown anti-inflammatory activity. After fractionation, cirsimaritin, eupatorin, and jaceosidin were found exclusively in the dichloromethane fraction and may have contributed to its anti-inflammatory activity. In addition, the anti-tyrosinase activity observed in the medium-polarity fractions may be associated with the presence of rutin, apigenin flavone glucoside, and 3-hydroxy-copalic acid. Conclusion: Overall, this study expands the chemical characterization of this medicinal plant and underscores its potential for skincare applications. Notably, anti-tyrosinase activity was identified in the medium-polar fractions for the first time, highlighting their potential as a source of bioactive metabolites relevant for cosmetic and skin- related applications.
The effect of Hortia oreadica Groppo (Rutaceae) extracts on the growth, feeding and digestive enzymes of Anticarsia gemmatalis Hübner [1818] (Erebidae)
(2026) Visôtto, Liliane Evangelista; Nasser, Vinícius Guimarães; Severino, Vanessa Gisele Pasqualotto; Soares, Márcio Santos; Faria, Vinícius Ribeiro; Good God, Pedro Ivo Vieira
The effects of four extracts of Hortia oreadica Groppo (Rutaceae) on the biological para- meters, nutritional indices, and activity of digestive enzymes of Anticarsia gemmatalis Hüb- ner [1818] (Erebidae) were evaluated. Newly hatched caterpillars were subjected to extracts from H. oreadica extracted with hexane (HE), dichloromethane (DE), dichloromethane fractionated with ethyl acetate (DEAE) and dichloromethane fractionated with dichlo- romethane (DDE) at concentrations 0, 100, 500 and 1000 μg ꞏ ml–1. The results showed that treatments significantly increased the cumulative mortality rate of A. gemmatalis and that HE 100 μg ꞏ ml–1 was the most effective, causing 92% of insects’ deaths. The period of larval development was significantly shorter with treatments HE 100 and 500 μg ꞏ ml–1 and longer with DEAE (all concentrations). The pupal weight was lower in the treatments HE 1000 μg ꞏ ml–1 and in all doses tested of the DEAE treatment. The morphological integrity of pupae and adults was not affected. The lowest values of relative food consumption rate, relative metabolic rate, and relative growth rate were observed in the HE 100 μg ꞏ ml–1 treat- ment. In most treatments, there was a reduction in the activity of total proteases, serine and cysteine proteases, and amylase. The results suggest that the HE extract of H. oreadica is the most efficient in controlling A. gemmatalis, due to the presence of deterrent metabolites that affect the insect’s digestion and nutrition and consequently promote adverse effects on its development and mortality.
Chemical profiling and cosmetic potential from anacardium humile and anacardium occidentale
(2026) Silva, Carlos Ferreira da; Santos, Noelle Cruz Faustino dos; Nascimento, Isabella Marques do; Silva, Cleysla Mendes da; Lopes, Patrícia Santos; Costa, Larissa S.; Sousa, Lorena Ramos Freitas de; Macêdo, Adriana Pereira Mundim Guedes; Coelho, Felipe Lange; Moraes, Carlos André Ferreira; Severino, Maico Roris; Severino, Vanessa Gisele Pasqualotto
Brazilian species of nutritional and economic importance, but their pseudofruits-especially A. humile-are underexplored. This study chemically profiles ethanolic extracts from mixed pseudofruits of both species, collected from two Goiaś regions, and evaluates their cosmeceutical potential. Chemical profiling was primarily performed by HPLC-ESI-QTOF-MS/MS combined with GNPS molecular networking, yielding putative annotations, while HNMR provided complementary chemical fingerprinting. Nine compounds were annotated by LC-MS/MS, mainly glycosylated flavonoids (quercetin and myricetin derivatives), together with a disaccharide and an anacardic acid. In addition, the 1H NMR spectra of the ethyl acetate fractions showed signals that support the presence of p-coumaric acid. The crude extracts showed low cytotoxicity in HaCaT cells (IC50 = 41.330 ± 1.618 mg/mL for AHB, 0.891 ± 0.079 mg/mL for AHK), with additional PrestoBlue data supporting safety. Enzyme assays revealed moderate elastase inhibition (up to 48.4 ± 4.0% at 100 μg/mL) and low tyrosinase inhibition (≈9%). The extracts also exhibited strong UV absorption (<300 nm) and photostability after UV exposure (254 and 363 nm for 8 h). These results suggest that Anacardium pseudofruits, with their flavonoid, hydroxycinnamate, and carotenoid profiles, are promising for antiaging/photoprotective applications.
Diagnosis of acetaminophen and codeine poisoning in a dog using earwax analysis by headspace gas chromatography-mass spectrometry (HS/GC-MS)
(2026) Vicente, Monica Chacon de; Barros, Alexandre Có Mangoni; Souza, Gabriela Scarpin de; Prado, Laís Di Paulie Taborda; Barbosa, João Marcos Gonçalves; Silva, Rayanne Henrique Santana da; Gomes, Leidiane de Souza; Martins, Danieli Brolo; Antoniosi Filho, Nelson Roberto; Botelho, Ana Flávia Machado
Poisoning of companion animals resulting from exposure to analgesics intended for human use is a frequent and clinically relevant problem in veterinary practice, usually associated with administration without professional supervision. This can induce severe systemic toxicity. Diagnostic confirmation can be particularly challenging in cases presenting with nonspecific clinical signs or when conventional biological samples are unavailable. This case report describes the innovative use of earwax as a non-invasive biological matrix for toxicological confirmation in veterinary medicine. A 9-year-old male mixed-breed dog was admitted following a traumatic accident and subsequent administration by its owner of a human medication containing acetaminophen and codeine. Clinical evaluation revealed lethargy, hypersalivation, hyporexia, dehydration, and neurological abnormalities. Laboratory findings demonstrated neutrophilic leukocytosis and marked increases in hepatic enzyme activities, consistent with acute hepatocellular injury. Toxicological investigation using headspace gas chromatography–mass spectrometry detected acetaminophen-related signatures in an earwax sample, supporting suspected exposure to the drug. Intensive treatment was promptly initiated and included fluid therapy, antidotal treatment with N-acetylcysteine, opioid antagonism, analgesia, and supportive care. The patient showed progressive clinical improvement, with complete resolution of clinical signs and full recovery. This case highlights the significant risks of administering human medications to companion animals and underscores the need to improve owner awareness of selfmedication practices. Furthermore, it demonstrates the diagnostic potential of earwax as a non-invasive biological matrix for toxicological confirmation, expanding the range of complementary diagnostic tools available for veterinary toxicology and supporting improved clinical decision-making in cases of suspected pharmaceutical intoxication.
Explorando plantas alimentícias não convencionais: estratégias sustentáveis para a segurança alimentar e a diversidade cultural
(2026) Oliveira, Yasmine Fernandes; Clemente, Alan Dumont; Oliveira, Jordana Jani da Silva; Rosa, Carlos Eduardo Tomé; Capistrano, Gradisca de Oliveira Werneck de; Mesquita, Nyuara Araújo da Silva; Severino, Vanessa Gisele Pasqualotto
Este artículo informa sobre la experiencia de una iniciativa de extensión universitaria con la comunidad local destinada a promover la inclusión de Plantas Alimenticias No Convencionales (PANC), con el objetivo de aumentar la conciencia sobre la sostenibilidad, la seguridad alimentaria y la apreciación de la biodiversidad. El estudio discute la relevancia de las PANC como herramientas educativas alineadas con los Objetivos de Desarrollo Sostenible (ODS), particularmente aquellos relacionados con la educación de calidad (ODS 4), el consumo responsable (ODS 12) y el hambre cero (ODS 2). Además, explora la sugerencia de incorporar este tema en la curricularización de la extensión como una estrategia para conectar la universidad con la comunidad, vinculando la formación académica con la discusión de problemas cotidianos y fomentando el desarrollo social y ambiental. Las actividades de extensión incluyeron talleres, cursos cortos y conferencias, que involucraron a diversos sectores de la sociedad en la promoción de prácticas alimentarias y ambientales más sostenibles. Los resultados destacan el papel transformador de las PANC en el proceso educativo y en la concienciación sobre el uso sostenible de los recursos naturales.
German soils affect biomass production, elemental profiles, and anti-inflammatory activity of three medicinal plants used in Brazilian traditional medicine: Scoparia dulcis L., Physalis angulata L., and Porophyllum ruderale (Jacq.) Cass.
(2026) B. Hernández, Enrique ; Gabor, Philipp; Schanbacher, Franziska; Severino, Vanessa Gisele Pasqualotto; Leandro, Wilson Mozena; Shaheen, Sabry Mohamed Nesiem; Melzig, Matthias Friedrich; Weng, Alexander; Rinklebe, Jörg
Cultivated medicinal plants are an important source of bioactive raw materials. However, information on their performance in non-native soils and their associated elemental and pharmacological profiles is limited. This study evaluated whether the three South American medicinal species – Physalis angulata L., Porophyllum ruderale (Jacq.) Cass., and Scoparia dulcis L. – can be cultivated on two German soils (clayey silt and sandy loam) under greenhouse conditions, focusing on biomass production, elemental profile, and anti-inflammatory potential. Soil and plant tissues were analyzed for macro-, micro-nutrients, and trace elements, including rare earth elements (REEs), using inductively coupled plasma mass spectrometry (ICP-MS) and inductively coupled plasma optical emission spectrometry (ICP-OES). Crude extracts were tested for anti-inflammatory activity in lipopolysaccharide-stimulated THP-1-derived macrophages. High-resolution mass spectrometry with class-level annotation was used to characterize major natural product classes. The three plant species produced satisfactory above-ground biomass, with P. ruderale yielding the highest biomass, and nutrient levels were within ranges considered adequate for plant growth. Potentially toxic elements (Ni, Cu, Zn, and REEs) were detected at subtoxic concentrations. REEs were largely retained in the roots, with limited translocation to the shoots, which supports the safe use of the above-ground biomass. Acetone extracts of P. angulata, enriched in limonoids (physalins), exhibited the strongest inhibition of pro-inflammatory cytokine secretion. In contrast, S. dulcis extracts were dominated by diterpenoids, exhibiting solvent- dependent activity. Overall, both soils supported the production of pharmacologically active biomass, demonstrating their potential as a reliable raw material for this purpose in a Central European agricultural setting.
A target-directed platform for identification of ligands of Schistosoma mansoni methylthioadenosine phosphorylase in natural product extracts
(2026) Amaral, Lucas Gonçalves do; Abreu, Miguel Franco Sepulvida de; Lessa, Renato Corrêa da Silva; Oliveira, Pamella Christina Ortega de; Amorim, Magali Silva de; Simão, Jorge Luiz Souza; Albino, Martin; Pereira, Humberto d'Muniz; Sangregorio, Claudio; Severino, Vanessa Gisele Pasqualotto; Moraes, Marcela Cristina de
5′-Methylthioadenosine phosphorylase from Schistosoma mansoni (SmMTAP) is a promising target within the parasite's purine salvage pathway. In this study, SmMTAP was covalently immobilized onto amine-functionalized cobalt ferrite magnetic nanoparticles (CoFe2O4), generating a reusable bioreactor (CoFe2O4@SmMTAP) with an immobilization efficiency of 66.3 ± 6.6%. Enzymatic activity was monitored by HPLC-DAD through the direct quantification of adenine using a validated analytical method (linearity 1–100 μmol/L, R2 = 0.9999; LOD 0.005 μmol/L; LOQ 0.01 μmol/L). The immobilized enzyme displayed Michaelis-Menten behavior (apparent KM = 29.45 ± 7.34 μmol/L), retained more than 60% residual activity over two weeks, and preserved more than 50% activity after seven reaction cycles. The platform was applied to the screening of eight natural product extracts, identifying the ethanolic stem extract from Hymenaea stigonocarpa as a potential source of SmMTAP inhibitors (IC50 = 8.29 ± 0.94 μg/mL). Affinity selection–mass spectrometry (AS-MS) with CoFe2O4@SmMTAP revealed six putative ligands (affinity ratios 1.45–2.89) in the crude extract. Analytical-scale microfractionation was con- ducted, specifically targeting the retention time windows of the ligands previously detected by AS-MS. This strategy successfully localized the main bioactive region to the 30.75–33.0 min window, which overlaps with the retention times of two ligands, including a compound tentatively annotated as asperphenamate. Complementary UHPLC–HRMS dereplication enabled the putative annotation of 23 compounds. Overall, the integrated workflow provided a selective, material-efficient, and reusable bioanalytical platform for screening SmMTAP inhibitors incomplex natural libraries.
Decanoic acid modulates cerebral metabolism and attenuates ischemic injury in a mouse model
(2026) Nunes, Antonio Ítalo dos Santos; David, Lurian Caetano; Cavalcante, Daniel Pereira; Carvalho, Gustavo Almeida de; Silva, Eduardo Rosa da; Leite, Jacqueline Alves; Antoniosi Filho, Nelson Roberto; Pinto, Mauro Cunha Xavier
Cerebral ischemia, resulting from acute interruption of cerebral blood flow, is a leading cause of long-term cognitive and motor disabilities, and current therapeutic options remain limited. Decanoic acid, a medium-chain fatty acid with antioxidant and anti-inflammatory properties, has been proposed as a potential neuroprotective agent. This study evaluated the neuroprotective and metabolic effects of decanoic acid in a murine model of permanent middle cerebral artery occlusion (MCAO). Male mice received decanoic acid (62.5, 125, or 250 mg/kg, oral gavage) or vehicle for 7 days after MCAO. Infarct volume was quantified by TTC staining. Motor and cognitive performance were assessed using the Cylinder, Limb Clasping, Object Location, and Novel Object Recognition tests. Metabolomic profiling (HS/GC–MS) of cortical tissue was performed to characterize ischemia-induced metabolic disturbances and treatment-related modulation of lipid and energy metabolism. Oxidative stress markers, antioxidant enzyme activities, and inflammatory cytokines (ELISA) were also measured in brain tissue. Decanoic acid significantly reduced total infarct volume and improved motor coordination and memory performance. Metabolomic analysis revealed that DA modulated metabolites disrupted by ischemia, partially restoring lipid and aldehyde homeostasis. Furthermore, treatment decreased lipid peroxidation, enhanced antioxidant enzyme activities, and effectively reversed the ischemia-induced elevation of pro-inflammatory cytokines, thereby neutralizing the neuroinflammatory response. These findings suggest that decanoic acid may exert a coordinated regulatory effect, contributing to neuroprotection through the modulation of cerebral metabolic homeostasis and attenuation of oxidative and inflammatory stress, and supporting its potential as a therapeutic candidate for ischemic brain injury
A methodology to determine additive markers in fuel ethanol using gas chromatography-mass spectrometry
(2026) Gonçalves, Leonardo Silva; Costa, Dyovanna de Sousa; Dias, Rhyan César Santos; Oliveira, Lilian Fernandes de; Aguiar, Aline Moreira; Costa, Dayane Cristina da; Barbosa, João Marcos Gonçalves; Oliveira, Anselmo Elcana de; Antoniosi Filho, Nelson Roberto
Ethanol has been increasingly utilized on a large scale as a biofuel. In Brazil, hydrated fuel ethanol is available in two types: regular (EHC) and a version known as additive ethanol (EHA), which contains multifunctional chemical compounds for enhanced performance. Each brand or distributor may select various additive packages for additive options. The detection of additives in fuels, such as gasoline and diesel, is widely discussed in scientific literature; however, methodologies capable of assessing the presence of these additives and correlating them with their origin are lacking. Thus, this study developed a new methodology to distinguish between EHA and EHC, and to identify fuel additives characteristic of the major brands available in the Brazilian market, using gas chromatography coupled with mass spectrometry (GC–MS) and a multivariate analysis-based approach. Overall, 198 commercial fuel ethanol samples were analyzed, 98 EHC and 99 EHA. A regression model built using 17 chemical compounds presented an accuracy of 97 %. Oleic acid, 2-ethylhexanol, and 1,4-diethylbenzene were identified as the main chemical markers. In summary, this study presents a rapid, robust, and highly accurate method for distinguishing between additive and regular hydrated fuel ethanol, representing a breakthrough in biofuel quality assurance. This advancement contributes significantly to ensuring the quality of biofuels, with direct impacts on environmental safety, preventing economic losses, and strengthening oversight and regulation in the sector.
Nano-confined NHC-Al interfaces for efficient CO2 chemical fixation
(2026) Silva, Blendo Almeida da; Ebersol, Camila Porto; Tomazett, Vinícius Kalil; Queiroz Junior, Luiz Henrique Keng; Sanches Neto, Flávio Olimpio; Oliveira, Heibbe Cristhian Benedito de; Santos, Francisco Paulo dos; Dupont, Jairton; Qadir, Muhammad Irfan
Nano-confined interfacial NHC-Al sites in Al2O3-supported ionic liquid phases (SILPs) act as engineered catalysts for selective CO2 fixation into epoxides, with NHC-Al adduct formation confirmed by solid-state nuclear magnetic resonance (NMR) and X-ray photoelectron spectroscopy (XPS). The synergistic combination of NHC-Al adducts and IL moieties generates membrane-like nano-confined environments at the solid–liquid interface. These confined environments regulate substrate access and product diffusion during CO2 absorption and fixation, which exhibit a high affinity for CO2 capture under mild reaction conditions. Size-selective transport within the nano-confined SILP architecture favors small-sized epoxides over bulky ones, leading to enhanced reaction rates and selectivity. The NHC@SILP-PMImAl2O3 catalyst, containing a lower fraction of NHC-Al adduct (15%) and a high proportion of imidazolium-chloride ion pairs, exhibited the highest activity, achieving a turnover frequency of 16.09 h−1 for epichlorohydrin at 1-bar CO2 and 70°C. In contrast, the NHC-Al SILPs with a high NHC-Al adduct (41%) showed a significantly reduced performance (59.1 TONs). This comparison highlights that catalytic efficiency is governed by a balance between NHC-Al formation and the availability of nucleophilic chloride species within the nano-confined environment. Chloride-assisted CO2 cycloaddition in SILPs proceeds via Al2O3 surface hydroxyl-mediated epoxide activation rather than imidazolium C2-H pathways typical of neat ionic liquids, as supported by density functional theory.
Presumptive semen detection using fructose as a forensic marker: comparison of colorimetric solution assays and paper-based analytical devices
(2026) Nascimento, Amanda Luise Alves; Anunciação, Daniela Santos; Coltro, Wendell Karlos Tomazelli; Santos, Josué Carinhanha Caldas
Identification of biological fluids is a fundamental step in criminal investigations, especially in sexual assault cases, which have a high global incidence. To prove the crime and identify the perpetrator, biological samples such as semen are collected from the crime scene or from the victim. Thus, this study aimed to develop an analytical methodology for detecting fructose (a chemical marker) in solutions and in paper-based analytical devices (PADs). The colorimetric response is due to the presence of fructose, which results in the formation of a blue chromophore (λ = 625 nm). Various parameters were optimized to improve the method's detectability and sensitivity, enabling a linear response over 0.5–3 mg L−1 (solution) and 12.5–150 mg L−1 (PAD). The limits of detection (LOD) were 0.17 mg L−1 and 6.25 mg L−1, respectively, demonstrating that the method fully meets the intended purpose. In addition, the methodologies showed recoveries between 91 and 102% and RSD ≤ 3.8%, evidencing the method's accuracy and precision. The methodologies evaluated on real samples demonstrated high sensitivity and reliability, even in the presence of potential interferences. A qualitative assessment (n ≥ 60) confirmed the strong performance of the assays, with a minimum sensitivity of 98%. Consequently, both methodologies allow for rapid qualitative and quantitative analyses directly at crime scenes, addressing key limitations of commercially available tests, particularly regarding response time and the risk of false positives. Moreover, these approaches have the potential to enhance public security by significantly reducing the time required to resolve criminal cases.
A portable platform with integrated colorimetric and electrochemical detection of nitrite and bisulfite in environmental and beverage samples
(2026) Souza, Gustavo R.; Guerra, Samuel Camargo; Alencar, Priscila Moreira de; Melo, Larissa Magalhães de Almeida; Santos, Daniel Júnior Almeida dos; Rocha, Manoelly Oliveira; Couto, Bruno Charles do; Carvalho, Rogério Mesquita de; Coltro, Wendell Karlos Tomazelli
Monitoring nitrite and bisulfite in environmental waters, beverages, and food products is highly relevant due to their regulatory limits and potential risks to human health. Existing analytical techniques often face limitations such as high cost, long analysis times, and environmental impact. In this study, a new colorimetric–electrochemical method was developed for the detection and quantification of nitrite and bisulfite, integrating bromocresol green (BG) as a colorimetric reagent with square-wave voltammetry (SWV) using laboratory-fabricated screen-printed graphite electrodes (SPE-Gr) and a 3D-printed platform. The method provides dual analytical information: a visible color change from yellow to blue/green and distinct electrochemical signals that enable the simultaneous identification of both analytes. The system requires low sample volumes (60 µL), supports portability, and is suitable for on-site applications with a low cost per analysis ($1.72). Under optimized conditions, linear responses were obtained in the ranges of 10–60 µmol L−1 for nitrite and 50–500 µmol L−1 for bisulfite, with limits of detection equal to 1.68 and 14.5 µmol L−1, respectively. The electrochemical response showed good stability across replicate and independent SPE-Gr devices (RSD < 2% for Ep and < 5% for Ip). Overall, the proposed methodology combines rapid screening with reliable quantification (recoveries of 90–145% and 71–113% for nitrite and bisulfite, respectively), providing a practical and selective alternative for environmental and beverage samples.
Blue-for-positive: colorimetric LAMP detection on paper-based microfluidic devices using a blue-shift indicator for instrument-free naked-eye readout
(2026) Vlachovsky, Sandra Gabriela; Anunciação, Daniela Santos; Coltro, Wendell Karlos Tomazelli; Santos, Josué Carinhanha Caldas
Loop-mediated isothermal amplification (LAMP) is a nucleic acid amplification method that allows the synthesis of large amounts of DNA in a short period of time with high specificity. Its operation at constant temperature, offers great potential for rapid diagnostics outside conventional laboratory settings. These features make LAMP suitable for point-of-care (POC) applications, but despite these promises, current POC detection methods require the use of dedicated equipment and relatively large reaction volumes, compromising the cost per reaction and the applicability. Results This study reports the use of a microfluidic paper-based analytical device (μPAD), which use less than 7 μL of LAMP reaction sample and produce an intense and contrasted blue color for positive samples offering naked-eye detection minimizing the user subjectivity and the cost per sample analysis. Its operation is based on the molybdate blue colorimetric and irreversible reaction happening in a μPAD, specifically optimized for the detection of pyrophosphate, a highly sensitive byproduct of nucleic acid amplification. As a proof of concept, the device was validated using LAMP products amplified from Candidatus Liberibacter asiaticus, the bacterium responsible for Huanglongbing (HLB) disease. μPADs exhibit sensitivity comparable to agarose gel electrophoresis method, detecting as low as 75 pg μL−1 of DNA template, and assays with HLB-infected citrus samples showed similar level of agreement. Significance This work presents a cutting-edge detection platform for molecular diagnosis offering novel, low-cost, and field-deployable μPADs that can be potentially integrated as a detection module in a microfluidic device combining the robustness and sensitivity of LAMP with the simplicity of paper-based colorimetric detection.

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