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Item type: Item , Sustainable avocado seed starch nanoparticles for limonene encapsulation: a novel immunomodulatory delivery system(2026) Alves, Guilherme Liberato; Ribeiro, Gislane Oliveira; Leal, Maria Carolina Bezerra Di Medeiros; Lião, Luciano Morais; Coelho, Luísa Coutinho; Bocca, Anamélia Lorenzetti; Leles, Maria Inês Gonçalves; Marreto, Ricardo NevesD-limonene is a bioactive monoterpene with recognized antioxidant, anti-inflammatory, and antimicrobial properties, whose therapeutic application is severely constrained by its high volatility, sensitivity to oxidation, and poor aqueous solubility. Nanoencapsulation within biopolymeric matrices represents a promising strategy to overcome these limitations. Therefore, this study aimed to develop and characterize chemically modified avocado seed (Persea americana Miller) starch nanoparticles, produced via a simple one-step nanoprecipitation method, for D-limonene encapsulation, evaluating their physicochemical properties, long-term stability, and immunomodulatory potential. Acetylation of the starch was confirmed by FTIR, ¹³C NMR, and degree of substitution (DS) determination, which collectively demonstrated successful introduction of acetyl groups into the polymer backbone and the resulting increase in hydrophobicity that underlies the encapsulation capacity of the nanocarrier. Thermogravimetric analysis further characterized the physicochemical properties of the modified starch and nanoparticles. The resulting nanoparticles displayed mean diameters lower than 350 nm, predominantly homogeneous size distributions (PdI<0.3), zeta potentials ranging from −10.46 to −13.77 mV and encapsulation efficiency higher than 80% in two formulations. Long-term stability assessment demonstrated preservation of colloidal integrity after 10 months under refrigerated storage, with retention of approximately 69% of initial encapsulation efficiency. TEM analysis revealed small, globular particles with smooth surfaces and narrow size distribution, while FT-IR spectroscopy provided surface chemistry characterization consistent with limonene confinement within the nanoparticle core. In vitro release studies demonstrated a sustained, gradual release profile, with 59.1% of the encapsulated DL released after 24 h and release kinetics best described by a first-order model, with Fickian diffusion as the dominant transport mechanism. Immunological analysis demonstrated a potent and context-dependent immunomodulatory potential of ASNP-DL1. In vitro assays showed the suppression of pro-inflammatory cytokines (TNF-α and IL-6) in macrophages and dendritic cells, concurrently maintaining anti-inflammatory IL-10 at basal levels, indicating a coordinated shift toward an anti-inflammatory phenotype. These findings underscore the potential of this sustainable nanocarrier as a versatile platform that effectively addresses the physicochemical limitations of D-limonene, positioning this sustainable, agriculturally-derived nanocarrier as a promising candidate for immunomodulatory therapies with broad pharmaceutical and biotechnological relevanceItem type: Item , Automated manufacturing of paper-based analytical devices through pen-plotting technique for depositing hydrophobic barriers and chromogenic reagents(2026) Souza, Leyllanne Katharinne Araújo de; Rocha, Danielly Santos; Romanholo, Pedro Victor Valadares; Sgobbi, Lívia Flório; Coltro, Wendell Karlos TomazelliThis report describes, for the first time, the use of the pen-plotting technique (PPT) for the fabrication of paper-based analytical devices (PADs) through two sequential steps. In brief, PPT was employed to delimiting microzones by dispensing hydrophobic barriers composed of manila copal resin (MCR) and depositing the chromogenic reagent chromeazurol S (CAS) within the detection zones for aluminum sensing. All experimental conditions including the bioink concentration, line spacing, drawing speed, applied force, and number of passes were successfully optimized to ensure reproducible fabricationt of PADs. The proposed device exhibited satisfactory selectivity and maintained analytical stability for 14 days under ambient conditions. As a proof of concept, the resulting device was applied for the colorimetric detection of Al3 + in tap water and pharmaceutical samples. The proposed method provided linear behavior versus the logarithmic function of the Al3 + concentration from 0.5 to 30 mg L−1, with a limit of detection of 1.2 mg L−1. The feasibility of the developed approach was further demonstrated through the analysis of aluminum hydroxide in antacid samples. The obtained results (59 ± 1 g L−1) revealed accuracy (97–109 %) and good agreement with the labelled concentration, showing no statistically significant difference compared to a reference technique (p < 0.05). The reported approach achieved a high analytical greenness score (0.9), thus highlighting its strong adherence to green chemistry principles. Lastly, the use of PPT emerges as a promising and scalable fabrication strategy for producing PADs at room temperature offering substantial potential for multipurpose applications.Item type: Item , Surface-engineered biochar–Cu-BTC hybrid for ultrasensitive dual detection of uric acid and nitrite(2026) Dhaffouli, Afef; Salazar Carballo, Pedro Ángel; Carinelli, Soledad; González Orive, Alejandro; Sgobbi, Lívia Flório; Slabon, Adam; Rodrigues, Bruno Vinicius ManzolliAn electrochemical sensor was developed for the simultaneous detection of uric acid (UA) and nitrite (NO2−) using a hybrid nanocomposite based on juniper seed-derived biochar and copper benzene-1,3,5-tricarboxylate (CuBTC). The biochar provides a sustainable and porous carbon matrix, while CuBTC offers abundant electroactive Cu sites and enhances the electrocatalytic properties of the composite, thereby improving analyte oxidation and signal resolution. To further increase conductivity and improve interfacial charge transfer, an electrochemical activation/reduction step via cyclic voltammetry was applied. The structural and surface properties of the modified material were systematically characterized by transmission electron microscopy (TEM), atomic force microscopy (AFM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDS), confirming successful integration of the hybrid components and their morphological compatibility. Electrochemical performance, evaluated by differential pulse voltammetry (DPV), revealed well-separated oxidation peaks for UA and NO2−, enabling simultaneous quantification. The sensor exhibited low detection limits of 22.6 nM for UA and 7.3 nM for NO2−, with two linear ranges for both analytes. High selectivity was demonstrated against common interfering species, including ascorbic acid, dopamine, glucose, hydroquinone, and inorganic ions. Analytical performance in spiked real samples showed recoveries ranging from 74.9% to 110%, with relative standard deviations below 5%, indicating acceptable accuracy and reproducibility. These results demonstrate that integrating sustainable biochar with CuBTC forms an efficient electrocatalytic interface for dual analyte detection, offering potential applications in biomedical diagnostics and environmental monitoring.Item type: Item , 1H HR-MAS NMR metabolomics uncovers coordinated metabolic response to water stress in transgenic Swingle citrumelo(2026) Oliveira, Caroline Silva de; Oliveira, Paola Dias de; Aparecido, Rafael do Prado; Vieira, Luiz Gonzaga Esteves; Lião, Luciano Morais; Carlos, Eduardo Fermino; Alcantara, Glaucia BrazUnderstanding the biochemical mechanisms underlying drought tolerance in citrus is essential for developing rootstocks adapted to water-deficit conditions. This study applied proton high resolution magic-angle spinning nuclear magnetic resonance (1 H HR-MAS NMR) combined with chemometrics to characterize the metabolism of leaves from conventional non-transgenic (NT) and transgenic (T35S) Swingle citrumelo plants overexpressing the P5CSF129A gene, responsible for proline overproduction. This approach enabled the identification of metabolic alterations throughout stress progression. Transgenic plants exhibited constitutive proline accumulation, accompanied by coordinated modulation of choline, fatty acids, glucose, and sucrose. These adjustments reflect the involvement of nitrogen, carbon, and lipid pathways, conferring osmotic and redox stabilities and supporting the maintenance of metabolic homeostasis under severe water deficit. The combination of 1 H HR‑MAS NMR and chemometrics proved to be a robust, non-destructive chemical tool for elucidating metabolic profiles in genetically modified plants, contributing to the understanding of molecular mechanisms underlying drought tolerance in citrus and supporting the development of rootstocks better adapted to climate change. These findings support the use of 1 H HR‑MAS NMR metabolomics for elucidating drought-response mechanisms and for advancing omics-driven breeding strategies in citrus.Item type: Item , TXCA-mediated synthesis of halogenated 4-aminocoumarins derivatives under mild conditions and in silico evaluation against Alzheimer's disease-related protein targets(2026) Carvalho, Maryelle Andrea Gobatto de; Alves, Vinicius Castanheira; Flores, Lara Madeira; Doerner, Carlos Vinicius; Hall, Tácia Katiane; Bortolatto, Cristiani Folharini; Sandjo, Louis Pergaud; Santos Neto, José Sebastião dos; Braga, Antonio Luiz; Assis, Francisco Favaro deA highly efficient and selective protocol for the halogenation of the C─H bond of 4-aminocoumarin derivatives is reported. This shows that the use of trihaloisocyanuric acids in the synthesis of aminocoumarin derivatives consists of obtaining pharmacologically important compounds using new strategies and transformations. The proposed method has a broad substrate scope and uses ethyl acetate as the solvent. The reaction scope evaluation of 4-aminocoumarins with different structural characteristics showed that the reaction tolerates electron-withdrawing groups (compounds 3d–f and 8c–e) and electron-donating groups (compounds 3b-c, 3g, 5, 7, and 8b). A sterically hindered group attached to the nitrogen at C4 was also tolerated in the bromination reaction (compound 3h), as well as an alkyl group (compound 7) and even the absence of a substituent on the nitrogen (compound 5). Molecular docking results show that, among the compounds tested, compound 3h stands out. Its predicted interactions with acetylcholinesterase (AChE), monoamine oxidase B (MAO-B), β-secretase enzyme (BACE), and N-methyl-D-aspartate receptors (NMDAR) suggest a promising profile for inhibiting these neurochemical enzymes and antagonizing glutamatergic NMDAR, potentially contributing to therapeutic strategies for neurodegenerative diseases such as Alzheimer’s disease.