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Evaluation of stability and anxiolytic potential of oil-in-water polysaccharide nanoemulsions loaded with chalcone (1E,4E)-1,5-bis(4-methoxyphenyl) penta-1,4-dien-3-one

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CHEMICAL PAPERS 2024年第17期78卷 9205-9222页

作者： do Nascimento, Joice Farias Abreu, Flavia Oliveira Monteiro da Silva Holanda, Taysse Castelo, Rachel Menezes dos Santos, Helcio Silva de Menezes, Jane Eire Silva Alencar Guedes, Jesyka Macedo Univ Estadual Ceara Program Nat Sci PPGCN Nat Polymers Lab BR-60714903 Fortaleza Brazil Univ Estadual Ceara Program Nat Sci PPGCN Nat Prod Chem Lab BR-60714903 Fortaleza Brazil

The desire for products that are healthier, safer, and better for the environment is on the rise in society. Chalcones are aromatic ketones with anxiolytic and antimicrobial properties. The limited solubility, bioavailability, and long-term stability of chalcones hinder their application. Nanoemulsions can be used as a drug transport system to address this problem. The primary objective of our research was to design nanoemulsions through ANOVA (NE) with nanoscale droplets that would maintain exceptional stability, optimizing the anxiolytic capacity of chalcones. Sodium alginate and chitosan were assessed as the continuous phase material, while commercial soybean oil and mineral oil were used as adjuvants, besides surfactant, for the oil phase composition of the droplets. Results showed that the addition of soybean oil improved significantly the stability of the formulations, as did the use of the alginate matrix. The optimal NE showed a nanometer-sized droplet (126 nm) and negative zeta-potential (- 42 mV), showing good stability under different conditions-it synergistically enhances the anxiolytic potential. The mode of operation is associated with the receptors of the serotonergic system (5-HT). Toxicity, locomotion and anxiety tests performed using the zebrafish animal model showed a promising dose (0.0325 mg/mL) for the development of compounds with anxiolytic properties.

关键词： Nanodroplets Chitosan Alginate Anxiety Zebrafish

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Cellulose nanocrystals from tucum fibers cultivated in Amazon Forest: extraction and characterization

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JOURNAL OF POLYMER RESEARCH 2024年第11期31卷 1-11页

作者： Vasques, Jose Carlos Mathias, Samir Leite Alves, Lucas Repecka Ribeiro Neto, Wilson Alves Lucas, Alessandra de Almeida de Menezes, Aparecido Junior Univ Fed Sao Carlos Grad Program Mat Sci Polymers Renewable Sources Grp GP2FR BR-18052780 Sorocaba SP Brazil Univ Fed Sao Carlos Dept Mat Engn DEMa Grad Program Mat Sci & Engn BR-13565905 Sao Carlos SP Brazil

The extraction of cellulose nanocrystals from tucum fibers has not been previously reported in the literature. In this way, tucum fibers underwent extraction processes to obtain cellulose nanocrystals, which were then characterized using techniques such as Fourier Transformed Infrared (FTIR), Transmission Electron Microscopy (TEM), X-ray diffraction (XRD), Thermogravimetry (TG), and chemical composition analysis. The results revealed that the cellulose nanocrystals extracted from tucum fibers exhibited a fine, needle-like morphology with lengths ranging from 50 to 350 nm and diameters from 7.5 to 32.7 nm. The chemical composition analysis showed a high presence of alphacellulose in the fibers (ca. 63.38%). FTIR analysis demonstrated characteristic bands of cellulosic materials, while TG analysis indicated higher ash content and lower Tonset in the cellulose nanocrystals. XRD analysis showed increased crystallinity of the nanocrystals. The study underscores the potential applications of these cellulose nanocrystals as reinforcement in nanocomposite materials, emphasizing their eco-friendly and sustainable nature.

关键词： Tucum lignocellulosic fibers Amazonian fibers Renewable sources Circular economy

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Sequencing-based methods for single-cell multi-omics studies

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Science China Chemistry 2023年第11期66卷 3024-3043页

作者： Shanshan Qin Songmei Liu Xiaocheng Weng Department of Clinical Laboratory Center for Gene DiagnosisProgram of Clinical Laboratory MedicineZhongnan Hospital of Wuhan UniversityWuhan 430072China College of Chemistry and Molecular Sciences Key Laboratory of Biomedical Polymers of Ministry of EducationWuhan UniversityWuhan 430072China

Single-cell multi-omics technologies have thrived in recent *** combined studies of different modalities in single cells have enabled comprehensive insights into the complex functional networks of vital biomacromolecules,thus paving the way for a thorough understanding of cell biology and *** this review,we focus on the advances of single-cell multi-omics technologies utilizing sequencing strategies and propose potential perspectives.

关键词： single-cell multi-omics multimodal studies sequencing methods

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Influence of different photoinitiatiors in the UV-LED curing of polyester acrylated varnishes

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JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH 2023年第1期20卷 393-402页

作者： Dossin, Ricardo Lavoratti, Alessandra Cercena, Rodrigo Dal-bo, Alexandre Goncalves Gregory Zimmermann, Matheus Vinicius Zattera, Ademir Jose Univ Caxias do Sul Lab Polymers Postgrad Program Proc gn & Technol En 1130 Getulio Vargas StBldg 5Room 205 BR-95070560 Caxias Do Sul RS Brazil Univ Extreme South Santa Catarina Postgrad Program Mat Sci & Engn Florianopolis SC Brazil

The search for environmentally friendly coatings has gained relevance in recent years. To circumvent the use of volatile organic compounds, ultraviolet light curing has attracted considerable attention, especially with the recent advances in light emitting diodes (LEDs), wherein one of the most important components is the photoinitiator. Since UV-LED curing has a narrower wavelength spectrum than regular UV curing, the choice of photoinitiator is crucial. In this study, the influence of six types of photoinitiators in the curing of polyester acrylate varnishes was investigated. The post-curing optical, thermal, mechanical, dynamic mechanical, and morphological properties of these varnishes were examined. All varnishes were completely cured, and the resins cured with LED 1711 and diphenyl (acyl) phosphine oxide exhibited the lowest post-curing photoyellowing. Satisfactory mechanical and dynamic mechanical properties were achieved for all samples. However, due to the thickness of the films, more studies are needed to optimize the surface roughness of the varnishes.

关键词： Photoinitiators Polyester Ultraviolet light-light emitting diode curing Coating

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Rheological and Structural Properties of k-Carrageenan/Xanthan Gum Gummies Architected With a New Natural Additive

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polymers FOR ADVANCED TECHNOLOGIES 2025年第2期36卷

作者： Valencia, German Ayala Moraes, Izabel Cristina Freitas Leandro, Gabriel Coelho Hilliou, Loic Univ Fed Santa Catarina Dept Chem & Food Engn Florianopolis Brazil Univ Sao Paulo Sch Anim Sci & Food Engn FZEA Dept Food Engn Postgrad Program Mat Sci & Engn Pirassununga Brazil Univ Minho Inst Polymers & Composites IPC Guimaraes Portugal

Biohybrids (BHs)based on bentonite and anthocyanins can be produced as alternatives to synthetic colorants. However, no information is available on the interaction of biohybrid with food system. This research studies the rheological properties of gummies containing k-carrageenan and xanthan gum incorporated with a BH. The incorporation of BH (<= 2% w/w) increased the flow consistency index and shear thinning effect in melted gummies at 85 degrees C. During cooling from 90 degrees C to 25 degrees C, the presence of BH altered the sol-gel transition temperature typical in carrageenan systems, probably by the formation of carrageenan complexes. At 25 degrees C, all gummies had a solid-like response with elastic modulus (G') higher than viscous modulus (G"). G' values increased linearly with BH concentration, and the linear viscoelastic region and breaking strain decreased with BH concentration, indicating that this natural additive acted as a reinforcing material.

关键词： carrageenan natural additives rheology soft materials xanthan gum

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Antimicrobial and mechanical performance of epoxy/graphene-based powder coatings

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IRANIAN POLYMER JOURNAL 2023年第1期32卷 1-11页

作者： Vanzetto, Andrielen B. Marocco, Marcos V. de Lima, Gabriel G. Beltrami, Lilian V. R. Zattera, Ademir J. Piazza, Diego Univ Caxias Do Sul UCS Postgrad Program Proc & Technol Engn PGEPROTEC Caxias Do Sul RS Brazil Univ Caxias Do Sul UCS Lab Polymers LPOL BR-95070490 Caxias Do Sul RS Brazil

Graphene-based coatings' properties have been thoroughly explored in some scientific and technological branches. However, their use in antimicrobial surfaces is still a developing field. The study of new methods of producing graphene-based coatings that have good mechanical and protective properties, microwave absorption performance and the superficial antimicrobial activity, presents itself as a necessary research. In this context, epoxy/graphene nanoplatelets powder coatings applied on carbon steel sheets were evaluated for their properties. An amount of 1 and 2% (by wt) of graphene nanoplatelets was added to the solid epoxy resin and homogenized by mixing processes without using solvents. They were characterized for tests of mechanical properties of adhesion, impact, and flexibility, for surface tension, brightness, antifouling and antimicrobial activity, and microwave absorption properties. The coatings showed excellent mechanical performance in terms of adhesion, impact resistance and flexibility. The graphene nanoplatelets provided greater hydrophobicity to the coatings, which had a contact angle greater than ?. The coatings containing graphene demonstrated great potential for the microwave absorption and antimicrobial surface. Different adhesion processes of marine aquatic organisms were observed, indicating the active role of the nanoparticle in the nanocomposite coating. These results indicated potential application of these coatings in different industries such as food, healthcare, maritime and defense.

关键词： Graphene Epoxy powder coatings Mechanical performance Antimicrobial surface Microwave absorption

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Beyond static: Tracking the dynamic nature of water absorption and Young's modulus in IPMC devices

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JOURNAL OF APPLIED POLYMER SCIENCE 2024年第31期141卷 e55730-e55730页

作者： Saccardo, Matheus Colovati Barbosa, Rafael Zuquello, Ariel G. Blanco, Guilherme Eduardo de Oliveira Tozzi, Kaique A. Goncalves, Roger Scuracchio, Carlos H. Univ Fed Sao Carlos Grad Program Mat Sci & Engn Sao Carlos SP Brazil Community Univ Chapeco Grad Program Technol & Innovat Management Chapeco SC Brazil Univ Jean Monnet Univ Claude Bernard Lyon 1 Univ Lyon CNRSUMR 5223INSA LyonIngn Mat Polymers F-42023 St Etienne 2 France Univ Fed Sao Carlos Dept Mat Sci Sao Carlos SP Brazil

Ionomeric polymer-metal composites (IPMC) are advanced materials designed to mimic biological systems. Their performance depends on various factors, including electrical stimulus intensity, membrane hydration, ionic migration, and Young's modulus. However, there is a lack of studies in the literature investigating how the water absorption capacity and elastic modulus change over time in IPMCs. Understanding the hydration level variation as a function of time is essential because as this parameter deviates, the ionic migration capacity and Young's modulus also change, altering the device's electromechanical efficiency over time. To address this research gap, Nafion/Pt-based IPMC devices exchanged with four monovalent cations (H+, Li+, Na+, and K+) and one ionic liquid (1-butyl-3-methylimidazolium-BMIM+) were prepared, and a comprehensive investigation on how the water absorption capacity and Young's modulus vary as a function of time, relative humidity (RH), and counterion size was performed. The results revealed that the water uptake capacity is significantly higher and occurs more rapidly at higher RH levels and when the counterion's ionic radius decreases. Consequently, the time required for the device to reach osmotic equilibrium can range from 40 to 270 min, depending on the RH and counterion used. Furthermore, it was observed that the first natural frequency and Young's modulus also exhibit time-dependent behavior. Under constant RH conditions, the mechanical properties of the IPMC can vary by up to 50% in less than 60 min. Notably, the combined results from water uptake capacity, Young's modulus, electrochemical impedance spectroscopy, and electromechanical response analyses (including blocking force, displacement, displacement rate, current, coulombic efficiency, and voltage) suggest that a morphological transformation within the polymer is likely to occur once RH exceeds 60%. This finding strengthens the hypothesis that ion migration is mainly influenced by

关键词： electromechanical devices electromechanical performance IPMC water absorption youngs modulus

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Development of graphite-reinforced PLA/PBAT composite filaments

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POLYMER COMPOSITES 2025年

作者： Figueiredo, Samuel Nogueira Dias, Alisson Rodrigues de Oliveira Leitao, Luigi Veloso Folkersma, Rudy Janssen, Kylian Sampaio, Arthur Antonio Sousa Almeida, Ilana Oliveira Azevedo, Joyce Batista de Carvalho, Laura Hecker Torres, Fabio Delano Penha Marques Barbosa, Renata Alves, Tatianny Soares Univ Fed Piaui Polymers & Conjugated Mat Lab LAPCON BR-64049550 Teresina Piaui Brazil NHL Stenden Univ Appl Sci Emmen Netherlands Univ Fed Bahia Inst Sci Technol & Innovat Camacari Brazil Univ Fed Campina Grande Postgrad Program Mat Sci & Engn Campina Grande Brazil

Additive manufacturing, particularly Fused Deposition Modeling (FDM), has been increasingly used due to its ability to create complex and personalized products. Besides, this processing technique can be performed with biodegradable polymers such as polylactic acid (PLA), a pioneer polymer in additive manufacturing profiles. Despite having a good set of desirable properties, the low impact strength and heat resistance of PLA limit its applications, which leads to studies on the use of different biodegradable polymers and additives. This study developed PLA/PBAT composite filaments with graphite (2.5%-12.5%) for FDM, evaluating their printability, microstructure, thermal, and mechanical properties. Morphological analysis showed homogeneous graphite dispersion, with the 7.5% graphite formulation (EC/7.5G) exhibiting optimal interlayer adhesion and minimal voids, yielding denser parts with superior printability. FTIR confirmed characteristic functional groups, while TGA indicated enhanced thermal stability, with the 12.5% graphite formulation (EC/12.5G) achieving the highest onset degradation temperature (T5 at 337.3 degrees C). Tensile tests revealed the 2.5% graphite formulation (EC/2.5G) had the highest elongation at break (815.57%), though the elastic modulus decreased with increasing graphite content. DMA showed improved storage modulus at lower temperatures, with the 7.5% graphite formulation balancing stiffness and ductility. Printed parts demonstrated high dimensional accuracy and surface finish. The 7.5% graphite formulation (EC/7.5G) emerged as the optimal composition, offering enhanced thermal stability, mechanical performance, and printability, making it a promising candidate for sustainable, functional 3D printing *** Novel composite filament developed by combining PLA, PBAT, and graphite. Graphite incorporation enhanced the thermal stability of the composite filaments. Sustainable and versatile filament alternative to conventional optio

关键词： 3D printing additive manufacturing biodegradable polymers composite filaments graphite PLA/PBAT blends

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Synthesis of luminescent chitosan-based carbon dots for Candida albicans bioimaging

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INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES 2023年第1期227卷 805-814页

作者： de Oliveira, Bruno Peixoto Bessa, Nathalia Uchoa de Castro do Nascimento, Joice Farias Cavalcante, Carolina Sidrim de Paula Fontenelle, Raquel Oliveira dos Santos Abreu, Flavia Oliveira Monteiro da Silva State Univ Ceara UECE Program Nat Sci BR-60714903 Fortaleza CE Brazil State Univ Ceara UECE Dept Chem Nat Polymers Lab BR-60714903 Fortaleza CE Brazil Fed Univ Cariri UFCA Educators Training Inst BR-63260000 Brejo Santo CE Brazil State Univ Ceara UECE Grad Program Sci BR-60714903 Fortaleza CE Brazil

In this work, we used chitosan as a raw material to synthesize carbon dots using fast microwave carbonization. We studied the influence of the synthesis time, doping agent, and the molar ratio between the reactants on the quantum yield of carbon dots. Chitosan-based carbon dots displayed stable blue fluorescence emission with excitation-dependent behavior and quantum yield values ranging from 1.16 to 7.07 %. ANOVA results showed that the interaction factor between the doping agent and the molar ratio of the reactants was a significant combination to produce carbon dots with higher quantum yield. The presence of the doping agent improved the carbon dots optical properties by obtaining higher fluorescence intensity values. Confocal laser microscope images showed that the carbon dots internalized in the Candida albicans cellular membrane, exhibiting blue, green, and red emissions, acting as a promising agent for bioimaging.

关键词： Carbon dots Chitosan Factorial design Quantum yield Bioimaging agent

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RNA modifications identification based on chemical reactions

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BIOORGANIC & MEDICINAL CHEMISTRY 2024年 111卷 117861页

作者： Zhao, Zhengjia Yan, Weikai Weng, Xiaocheng Wuhan Univ Zhongnan Hosp Ctr Gene Diag Wuhan Peoples R China Wuhan Univ Zhongnan Hosp Program Clin Lab Med Wuhan Peoples R China Wuhan Univ Coll Chem & Mol Sci Key Lab Biomed Polymers Minist Educ Wuhan 430072 Peoples R China

RNA modification identification is an emerging field in epigenetics due to its indispensable regulatory role in the cell life cycle. With advancements in identification methods, an increasing number of RNA modifications has been discovered, thereby driving the development of more efficient and accurate techniques for localizing modified RNAs and elucidating their functions. High-throughput sequencing approaches for modified RNA detection can be categorized into antibody-based, enzymatic-based, and chemical-labeling-based methods. Given the intrinsic chemical reactions involved in all biochemical processes, we provide a comprehensive review of recent advancements in artificial chemical labeling and transformations of ten distinct RNA modifications and their applications in sequencing. Our aim is to contribute to a deeper understanding of the mechanisms underlying these modifications. We focus on the chemical reactions associated with RNA modifications and briefly compare the advantages and disadvantages of detection methods based on these reactions. Additionally, we introduce several approaches that identify multiple modifications through chemical labeling. As the field of RNA modification research continues to expand, we anticipate that the techniques and insights presented in this review will serve as a valuable resource for future studies aimed at further elucidating the functional roles of RNA modifications in biological processes.

关键词： RNA modification Chemical labeling Sequencing

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