151 research outputs found

    Electrospray Deposition of PEDOT:PSS on Carbon Yarn Electrodes for Solid-State Flexible Supercapacitors

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    Funding Information: This work was financed by national funds from FCT─Fundação para a Ciência e a Tecnologia, I.P., in the scope of the All-FIBRE project with the reference PTDC/CTM-CTM/1571/2020, and the projects LA/P/0037/2020, UIDP/50025/2020, and UIDB/50025/2020 of the Associate Laboratory Institute of Nanostructures, Nanomodelling, and Nanofabrication─i3N. This work was also supported by ERC-CoG-2014, CapTherPV, 647596. The authors would like to thank Professor Daniela Gomes from CENIMAT for the SEM images. Publisher Copyright: © 2023 The Authors. Published by American Chemical Society.The increasing demand for flexible electronic devices has risen due to the high interest in electronic textiles (e-textiles). Consequently, the urge to power e-textiles has sparked enormous interest in flexible energy storage devices. One-dimensional (1D) configuration supercapacitors are the most promising technology for textile applications, but often their production involves complex synthesis techniques and expensive materials. This work unveils the use of the novel electrospray deposition (ESD) technique for the deposition of poly(3,4-ethylenedioxythiophene)-poly(styrene sulfonate) (PEDOT:PSS). This deposition methodology on conductive carbon yarns creates flexible electrodes with a high surface area. The deposition conditions of PEDOT:PSS were optimized, and their influence on the electrochemical performance of a 1D symmetric supercapacitor with a cellulose-based gel as an electrolyte and a separator was evaluated. The tests herein reported show that these capacitors exhibited a high specific capacitance of 72 mF g-1, an excellent cyclability of more than 85% capacitance retention after 1500 cycles, and an outstanding capability of bending.publishersversionpublishe

    Magnetic Chitosan Bionanocomposite Films as a Versatile Platform for Biomedical Hyperthermia

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    Responsive magnetic nanomaterials offer significant advantages for innovative therapies, for instance, in cancer treatments that exploit on-demand delivery on alternating magnetic field (AMF) stimulus. In this work, biocompatible magnetic bionanocomposite films are fabricated from chitosan by film casting with incorporation of magnetite nanoparticles (MNPs) produced by facile one pot synthesis. The influence of synthesis conditions and MNP concentration on the films’ heating efficiency and heat dissipation are evaluated through spatio-temporal mapping of the surface temperature changes by video-thermography. The cast films have a thickness below 100 µm, and upon exposure to AMF (663 kHz, 12.8 kA m−1), induce exceptionally strong heating, reaching a maximum temperature increase of 82 °C within 270 s irradiation. Further, it is demonstrated that the films can serve as substrates that supply heat for multiple hyperthermia scenarios, including: i) non-contact automated heating of cell culture medium, ii) heating of gelatine-based hydrogels of different shapes, and iii) killing of cancerous melanoma cells. The films are versatile components for non-contact stimulus with translational potential in multiple biomedical applications. © 2023 The Authors. Advanced Healthcare Materials published by Wiley-VCH GmbH.This work was developed within the scope of the projects CICECO– Aveiro Institute of Materials UIDB/50011/2020, UIDP/50011/2020 &LA/P/0006/2020, CESAM -UIDP/50017/2020, and UIDB/50017/2020 andLA/P/0094/2020 and M-ERA-NET2/0021/2016 – BIOFOODPACK – Bio-composite Packaging for Active Preservation of Food. A.B. is thankfulto FCT for grant SFRH/BD/148856/2019. C.N. is grateful to the Por-tuguese national funds (OE) through FCT IP in the scope of the frame-work contract foreseen in the numbers 4, 5, and 6 of the Article 23of the Decree-Law 57/2016 of August 29 changed by Law 57/2017 ofJuly 19. J.K.W., D.W., and D.F.B. acknowledge support from the ScienceFoundation Ireland (16/IA/4584). E.R.-H. acknowledges financial supportfrom the MCIN/AEI/10.13039/501100011033 (Spain, project PID2019-105479RB-I00). M.M.C. and L.P.F. acknowledge FCT for Centre grantsUIDB/04046/2020 and UIDP/04046/2020 to BioISI. Part of the work in this article is based on the mobility exchange program of COST ActionCA18132, supported by COST (European Cooperation in Science and Tech-nology). FCT is also acknowledged for the research contract under Scien-tific Employment Stimulus to H.O. (CEECIND/04050/2017).Open access funding provided by IReLSupporting InformationPeer reviewe

    Suppressing cyanobacterial dominance by UV-LED TiO2-photocatalysis in a drinking water reservoir: a mesocosm study.

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    Cyanobacteria and their toxic secondary metabolites present challenges for water treatment globally. In this study we have assessed TiO2 immobilized onto recycled foamed glass beads by a facile calcination method, combined in treatment units with 365 nm UV-LEDs. The treatment system was deployed in mesocosms within a eutrophic Brazilian drinking water reservoir. The treatment units were deployed for 7 days and suppressed cyanobacterial abundance by 85%, while at the same time enhancing other water quality parameters; turbidity and transparency improved by 40 and 81% respectively. Genomic analysis of the microbiota in the treated mesocosms revealed that the composition of the cyanobacterial community was affected and the abundance of Bacteroidetes and Proteobacteria increased during cyanobacterial suppression. The effect of the treatment on zooplankton and other eukaryotes was also monitored. The abundance of zooplankton decreased while Chrysophyte and Alveolata loadings increased. The results of this proof-of-concept study demonstrate the potential for full-scale, in-reservoir application of advanced oxidation processes as complementary water treatment processes

    Screening, production and biochemical characterization of a new fibrinolytic enzyme produced by Streptomyces sp. (Streptomycetaceae) isolated from Amazonian lichens

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    Thrombosis is a pathophysiological disorder caused by accumulation of fibrin in the blood. Fibrinolytic proteases with potent thrombolytic activity have been produced by diverse microbial sources. Considering the microbial biodiversity of the Amazon region, this study aimed at the screening, production and biochemical characterization of a fibrinolytic enzyme produced by Streptomyces sp. isolated from Amazonian lichens. The strain Streptomyces DPUA1576 showed the highest fibrinolytic activity, which was 283 mm2. Three variables at two levels were used to assess their effects on the fibrinolytic production. The parameters studied were agitation (0.28 - 1.12 g), temperature (28 - 36 ºC) and pH (6.0 - 8.0); all of them had significant effects on the fibrinolytic production. The maximum fibrinolytic activity (304 mm2) was observed at 1.12 g, 28 ºC, and pH of 8.0. The crude extract of the fermentation broth was used to assess the biochemical properties of the enzyme. Protease and fibrinolytic activities were stable during 6 h, at a pH ranging from 6.8 to 8.4 and 5.8 to 9.2, respectively. Optimum temperature for protease activity ranged between 35 and 55 °C, while the highest fibrinolytic activity was observed at 45 ºC. Proteolytic activity was inhibited by Cu2+ and Co2+ ions, phenylmethylsulfonyl fluoride (PMSF) and pepstatin A, which suggests that the enzyme is a serine protease. Enzymatic extract cleaved fibrinogen at the subunits A-chain, A-chain, and -chain. The results indicated that Streptomyces sp. DPUA 1576 produces enzymes with fibrinolytic and fibrinogenolytic activity, enzymes with an important application in the pharmaceutical industry.The authors grateful acknowledge the financial support of Fundação de Amparo a Pesquisa do Estado de Pernambuco (FACEPE, Pernambuco, Brazil, N. 0158-2.12/11), CNPq/ RENORBIO (National Counsel of Technological and Scientific Development, N.55146/2010-3) and National Council for the Improvement of Higher Education (CAPES, Brazil) for the scholarship. The author thanks editor and reviewers for their review and comments.info:eu-repo/semantics/publishedVersio

    Glutamine dipeptide supplementation improves clinical responses in patients with diabetic foot syndrome

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    ABSTRACT The effect of glutamine dipeptide (GDP) supplementation in patients with diabetic foot syndrome was evaluated. A total of 22 patients took part in the study. GDP was supplied in 10 g sachets, and was dissolved in water immediately before use, with ingestion once a day, after lunch or after dinner (20 g/day) over a period of 30 days. Quantification of foot insensitive areas, oxidative stress, blood cytokines, and biochemical, hematological and toxicological parameters was performed before and after GDP supplementation. We observed an increase in blood levels of interferon-&#945; (P=0.023), interferon-&#947; (P=0.038), interleukin-4 (P=0.003), interleukin-6 (P=0.0025), interleukin-7 (P=0.028), interleukin-12 p40 (P=0.017), interleukin-13 (P=0.001), leukocytes (P=0.037), eosinophils (P=0.049), and typical lymphocytes (P<0.001) due to GDP administration. In addition, we observed a reduced number (P=0.048) of insensitive areas on the foot, and reduction (P=0.047) of fasting hyperglycemia. Patients also showed increased blood high density lipoprotein (P<0.01) and protein thiol groups (P=0.004). These favorable results were associated with the absence of renal and hepatic toxicity. These results are of clinical relevance, since supplementation with GDP over 30 days improved clinical responses in patients with diabetic foot syndrome
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