INSTITUTO DE PESQUISAS ENERGÉTICAS E NUCLEARES
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  • IPEN-DOC 30157

    TEODORO, LARA E.H. ; TALACIMON, CRISTHIAN F. ; RIGO, MARIA E.Z. ; RODRIGUES, PRISCILA S. ; NOGUEIRA, THUANY C. ; ROSERO, WILMMER A.A. ; VIEIRA, JOSE M. ; ZEITUNI, CARLOS A. ; ROSTELATO, MARIA E.C.M. . Possible molds for a new brachytherapy source for spinal and intracranial cancer. In: BRAZIL MRS MEETING, 21st, October 1-5, 2023, Maceió, AL. Abstract... São Carlos, SP: Aptor Software, 2023. p. 461-461.

    Abstract: Central Nervous System (CNS) cancer is the 18th most incident cancer in the world, according to the World Health Organization (WHO), and in 2020, in Brazil, it represented 2.5% of all new cancer deaths [1]. Brachytherapy is a type of radiotherapy that positions the radioactive source close to (or in contact with) the tumor. Thus, the targeted region receives most of the dose, protecting the healthy tissues adjacent to the tumor. A promising radioactive source for use in brachytherapy for the treatment of CNS cancer is phosphorus-32 in a polymeric substrate. This source has been prominent as a minimally invasive treatment for craniopharyngiomas and in the treatment of metastatic bone diseases in general [2]. To produce such a source, it is necessary to search for possible molds that can conform the polymeric material into the desired format. Several tests were carried out to determine the best mold for the radioactive source manufacture. Different materials were tested to observe if the mold material would react with the source's components, silicone rubber mixed with orthophosphoric acid. In order to be considered a possible mold, the mixture should cure; if the cure did not concretize, the mold would be descarted. It was concluded that polystyrene (PS) obtained the best result, due to the ease of unmold after the resin curing process.

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  • IPEN-DOC 24337

    COTA, STELA; HIROMOTO, GORO ; GHARBIEH, HEIDAR; SILVA, AURELIO. Preliminary post-closure safety assessment for a borehole-type repository for disused sealed radioactive sources in Brazil. Progress in Nuclear Energy, v. 103, p. 74-80, 2018. DOI: 10.1016/j.pnucene.2017.11.005

    Abstract: Brazil has a relatively large inventory of disused sealed radioactive sources (DSRSs). Until now, no decision has yet been made about the final destination of this category of radioactive wastes, although a repatriation of a small fraction of these sources comprising mainly neutron and high activity sources was already carried out. Borehole type repositories are one disposal solution considered for DSRSs in Brazil. This paper addresses a preliminary post-closure safety assessment for such a facility, using the borehole disposal concept (BDC) applied to different geological conditions and a range of projected inventories. Results from running the AMBER code considering deterministic and stochastic approaches showed that Am-241 is the main source of potential concern in order to comply with the effective dose constraint of 0.3 mSv/y and allowed the establishment of the relation between the maximum Am-241 inventory and the hydraulic conductivity of the geosphere.

    Palavras-Chave: safety; boreholes; brazil; abandoned shafts; radioactive wastes; sealed sources; radioactive waste disposal

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  • IPEN-DOC 27631

    COSTA, ROBSON S. ; ARAUJO, DANIELLE G. ; ANDRADE, MARCIO S. de ; OLIVEIRA, RENE R. ; RANGARI, VIJAYA; MOURA, ESPERIDIANA A.B. ; DIAS, FRANCISCO V.. Production and characterization of PBAT reinforced with clay and graphene oxide nanosheets: a comparative study. In: LI, JIAN (Ed.); ZHANG, MINGMING (Ed.); LI, BOWEN (Ed.); MONTEIRO, SERGIO N. (Ed.); IKHMAYIES, SHADIA (Ed.); KALAY, YUNUS E. (Ed.); HWANG, JIANN-YANG (Ed.); ESCOBEDO-DIAZ, JUAN P. (Ed.); CARPENTER, JOHN S. (Ed.); BROWN, ANDREW D. (Ed.). Characterization of Minerals, Metals, and Materials. Cham, CZ, Switzerland: Springer Nature Switzerland AG, 2020. p. 689-699, (The Minerals, Metals & Materials Series). DOI: 10.1007/978-3-030-36628-5_68

    Abstract: The poly (butylene adipate-co-terephthalate) (PBAT), a biodegradable polymer, is among the most promising materials to be considered as environmentally friendly high performance biodegradable plastics. However, the mechanical properties of PBAT are not the best for several applications. According to the literature, the properties of the biodegradable polymer can be improved by addition of a small amount of nanofillers, such as clay, silica, and graphene. The objective of this study is to compare the effect of the addition of Cloisite clay and graphene oxide (GO) on the properties of flexible films based on PBAT matrix. The composite films based on PBAT with addition of Cloisite (2.0 wt%) and PBAT composite films with addition of Cloisite and GO (0.1–0.2 wt%) were prepared by extrusion, using a twin-screw extruder and a flat die single extruder. The effects of the addition of Cloisite clay and graphene oxide on mechanical and thermal properties of films were evaluated by mechanical and water absorption tests, FE-SEM, XRD, and Raman analysis.

    Palavras-Chave: graphene; oxide minerals; nanocomposites; polymers; butenes; biodegradation; mechanical properties; flexibility

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  • IPEN-DOC 28983

    SAKATA, SOLANGE K. ; JACOVONE, RAYNARA M.S. . Redução do oxido de grafeno via radiação ionizante / Reduced graphene oxide via ionizing radiation. In: COLLET-LACOSTE, JUAN R. (Org.). Nanociências e Nanotecnologia: Pesquisa e Aplicações. Curitiba, PR: Artemis, 2022. p. 49-60, cap. 4. DOI: 10.37572/EdArt_2908226684

    Abstract: A radiação ionizante, o que inclui a radiação gama e feixe de elétrons, é considerada como “síntese verde” e “ambientalmente amigável” e vem se destacando como uma promissora rota sintética para obter óxido de grafeno reduzido. Essas reações ocorrem em meio aquoso, a temperatura e pressão ambiente, sem o uso de redutores tóxicos e geração de resíduos químicos tóxicos. Neste capítulo é apresentado uma compilação de estudos sobre redução do óxido de grafeno via radiação ionizante reportados na literatura na última década. A redução parcial do óxido de grafeno produz óxido de grafeno reduzido (rOG), um nanomaterial que combina as propriedades do grafeno e do óxido de grafeno: uma excelente condutividade elétrica e térmica e os demais grupos de oxigênio que permitem sua funcionalização. Na literatura, são descritas diversas rotas sintéticas para produzir rOG: por método químico, térmico, eletroquímico, radiação não ionizante e biocatalíticas.

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  • IPEN-DOC 27583

    LIMA, CAROLINE S.A. de ; VARCA, JUSTINE P.R.O. ; NOGUEIRA, KAMILA M. ; FAZOLIN, GABRIELA N. ; FREITAS, LUCAS F. de ; SOUZA, ELISEU W. de; LUGAO, ADEMAR B. ; VARCA, GUSTAVO H.C. . Semi-solid pharmaceutical formulations for the delivery of papain nanoparticles. Pharmaceutics, v. 12, n. 12, p. 1-12, 2020. DOI: 10.3390/pharmaceutics12121170

    Abstract: Papain is a therapeutic enzyme with restricted applications due to associated allergenic reactions. Papain nanoparticles have shown to be safe for biomedical use, although a method for proper drug loading and release remains to be developed. Thus, the objective of this work was to develop and assess the stability of papain nanoparticles in a prototype semi-solid formulation suitable for dermatological or topical administrations. Papain nanoparticles of 7.0 ± 0.1 nm were synthesized and loaded into carboxymethylcellulose- and poly(vinyl alcohol)-based gels. The formulations were then assayed for preliminary stability, enzyme activity, cytotoxicity studies, and characterized according to their microstructures and protein distribution. The formulations were suitable for papain nanoparticle loading and provided a stable environment for the nanoparticles. The enzyme distribution along the gel matrix was homogeneous for all the formulations, and the proteolytic activity was preserved after the gel preparation. Both gels presented a slow release of the papain nanoparticles for four days. Cell viability assays revealed no potential cytotoxicity, and the presence of the nanoparticles did not alter the microstructure of the gel. The developed systems presented a potential for biomedical applications, either as drug delivery systems for papain nanoparticles and/or its complexes.

    Palavras-Chave: papain; nanoparticles; drugs; gels; proteins

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  • IPEN-DOC 26883

    FAZOLIN, GABRIELA N. ; VARCA, GUSTAVO H.C. ; FREITAS, LUCAS F. de ; ROKITA, BOZENA; KADLUBOWSKI, SLAWOMIR; LUGAO, ADEMAR B. . Simultaneous intramolecular crosslinking and sterilization of papain nanoparticles by gamma radiation. Radiation Physics and Chemistry, v. 171, p. 1-7, 2020. DOI: 10.1016/j.radphyschem.2020.108697

    Abstract: Papain-based nanoparticles were recently developed using radiation technologies and proven effective to generate nanosized crosslinked papain particles with preserved enzymatic activity. The applications of such nanostructured systems are expected to be similar to native papain with considerable biopharmaceutical advantages and concern drug loading among other biotechnological applications. The nature of such crosslinks and the possibility to provide simultaneous sterilization have been hypothesized but remain not totally clarified. This manuscript advances the discussion on the radiation-induced synthesis of protein nanoparticles by approaching the nature of the crosslinking and the possible contribution of bityrosine linkages and disulfide bridges to the overall nanoparticle assembly as well as the feasibility of the simultaneous sterilization process under the preestablished conditions of processing. Papain nanoparticles were synthesized and characterized according to size, proteolytic activity, bityrosine, cysteine content and molecular weight by SDS-PAGE upon sonication at 40 kHz. Bacterial identification and the sterility tests were performed in accordance with ISO 11737 prior to and after inoculating 106 CFU of Corynebacterium xerosis. Our experiments evidenced the crosslinking of rather intra- than intermolecular nature and a contribution of cysteine bridges and bityrosine linkages to the stabilization and formation of the papain nanoparticle assembly. The technique was effective to promote simultaneous crosslinking and sterilization at the established conditions of processing and may be validated in accordance with the ISO 11137.

    Palavras-Chave: papain; sh-proteinases; nanoparticles; gamma radiation; proteins; cross-linking; sterilization; bacteria; disulfides

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  • IPEN-DOC 29195

    SANTOS, BIANCA P.S. ; KODAMA, YASKO ; SANTIAGO, ELISABETE I. . Synthesis and characterization of fluoropolymer membrane using RIG and reversible addition-fragmentation- chain-transfer (RAFT) method for fuel cell application. In: BRAZIL MRS MEETING, 20th, September 25-29, 2022, Foz do Iguaçu, PR. Abstract... São Carlos, SP: Aptor Software, 2022.

    Abstract: Anion exchange fuel cells (AEMFC) have attracted widespread attention in the last years and are considered one of the most promising environmentally friendly power generations. An auspicious way to produce well-controlled structures for applications as anion exchange membrane is using the radiation-induced grafting method (RIG) with RAFT agents [1]. RAFT consists of a reversible addition fragmentation chain transfer of free radicals and allows the control over polymeric molecular weight and copolymer topology and other properties. Ethylene tetrafluoroethylene (ETFE) is a type of fluoropolymer that can be applied in AEM due to its lightweight, excellent chemical and thermodynamic stability, and greater resistance to radiation ageing [2]. In this study, we investigated the beneficial outcomes of performing the ETFE-AEM synthesis in a fully controlled manner by RAFT polymerization using RIG. The influence of RAFT agent on physical (mechanical behavior, dimension), chemical (such as IEC), thermal properties (TGA and DSC) were investigated in detail for future and evaluated in AEMFCs. ETFE-grafting-Vinylbenzyl chloride (VBC) using RAFT agent controlled grafting degree of membrane and improved mechanical properties compared to conventional method of grafting.

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  • IPEN-DOC 28864

    BALOGH, TATIANA S. ; BONTURIM, EVERTON; VIEIRA, LUCAS D.; LUGAO, ADEMAR B. ; KADLUBOWSKI, SLAWOMIR. Synthesis of poly(N-vinyl pyrrolidone) (PVP) nanogels by gamma irradiation using different saturation atmospheres. Radiation Physics and Chemistry, v. 198, p. 1-11, 2022. DOI: 10.1016/j.radphyschem.2022.110238

    Abstract: Nanogels are internally crosslinked particles of nanometric size used in various fields e.g. as such as carriers in drug delivery systems. They can be produced using ionizing radiation in dilute aqueous solutions. This method is carried out in a pure polymer-solvent system, avoiding the addition of any additives such as monomers, surfactants, catalysts and crosslinking agents and no further purification step is necessary. Poly(N-vinyl pyrrolidone) (PVP K-90) nanogels were prepared by gamma irradiation in an aqueous solution. The samples were prepared in triplicate in multipurpose cobalt-60 gamma irradiator using 1, 10, 25 and 100 mM PVP solutions. Samples were irradiated in argon and nitrous oxide conditions with doses from 1 kGy up to 25 kGy with 10 kGy/h dose rate. The mean particle size (Rh) was determined by Dynamic Light Scattering (DLS) and radius of gyration (Rg) and weight-average molecular weight (Mw) by Static Light Scattering (SLS). These samples were morphologically characterized using Atomic Force Microscopy (AFM) and Transmission Electron Microscopy (TEM). Samples prepared with 100 mM PVP K-90 solution formed macroscopic gels, in the samples obtained with 25 mM PVP K-90 solution there was a prevalence of intermolecular crosslinking. On the other hand, in the samples generated with 10 mM PVP K-90 solution, there was a predominance of intramolecular crosslinking demonstrated in the tendency to: decrease in the radius of gyration (Rg), in the constancy of the weight-average molecular weight (Mw), in the increase in polymer coil density (ρcoil), in the Rg/Rh ratio (shape factor) around 1.0 indicating homogenous, internally cross-linked spheres, in the high relief spherical structures observed in the AFM images and in the spherical particles with high contrast observed in the TEM images. The saturation of the samples with nitrous oxide doubled formation of hydroxyl radicals, favoring the generation of polymeric radicals. Higher average number of radicals in each macromolecule contributed to the higher number of intramolecular crosslinks.

    Palavras-Chave: nanostructures; gels; argon; nitrous oxide; gamma radiation; pvp; cross-linking; molecular weight

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  • IPEN-DOC 28693

    SOUZA, CARLA D. de ; BARBEZAN, ANGELICA B. ; ROSERO, WILMMER A.A. ; SANTOS, SOFIA N. dos ; CARVALHO, DIEGO V. de S. ; ZEITUNI, CARLOS A. ; BERNARDES, EMERSON S. ; VIEIRA, DANIEL P. ; SPENCER, PATRICK J. ; RIBEIRO, MARTHA S. ; ROSTELATO, MARIA E.C.M. . Synthesis, in vitro testing, and biodistribution of surfactant-free radioactive nanoparticles for cancer treatment. Nanomaterials, v. 12, n. 2, p. 1-13, 2022. DOI: 10.3390/nano12020187

    Abstract: New forms of cancer treatment, which are effective, have simple manufacturing processes, and easily transportable, are of the utmost necessity. In this work, a methodology for the synthesis of radioactive Gold-198 nanoparticles without the use of surfactants was described. The nuclear activated Gold-198 foils were transformed into H198AuCl4 by dissolution using aqua regia, following a set of steps in a specially designed leak-tight setup. Gold-198 nanoparticles were synthesized using a citrate reduction stabilized with PEG. In addition, TEM results for the non-radioactive product presented an average size of 11.0 nm. The DLS and results for the radioactive 198AuNPs presented an average size of 8.7 nm. Moreover, the DLS results for the PEG-198AuNPs presented a 32.6 nm average size. Cell line tests showed no cytotoxic effect in any period and the concentrations were evaluated. Furthermore, in vivo testing showed a high biological uptake in the tumor and a cancer growth arrest.

    Palavras-Chave: radioactivity; nanoparticles; brachytherapy; neoplasms; testing; in vivo; in vitro; gold 198; distribution

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  • IPEN-DOC 29887

    SANTOS, BIANCA P.S. ; BARBOSA, ANDREY S. ; KODAMA, YASKO ; THIAGO, QUEIROZ B. de; SANTIAGO, ELISABETE I. . Tailoring highly stable anion exchange membranes with graft molecular structure ordering using reversible addition-fragmentation chain transfer polymerization for alkaline fuel cells. Journal of Membrane Science, v. 687, p. 1-12, 2023. DOI: 10.1016/j.memsci.2023.122071

    Abstract: The radiation-induced grafting is used to prepare a variety of anion-exchange membranes (AEM) based on poly (ethylene-co-tetrafluoroethylene) (ETFE) utilizing a reversible addition-fragmentation chain transfer (RAFT) agent. The copolymerization process is controlled by the RAFT agent, resulting in AEMs with a restricted molecular weight dispersion. As a result, RAFT-AEMs exhibit decreased water uptake and reduced swelling. A significant improvement in thermal and mechanical characteristics is evidenced, while the conductivity remains practically unaltered. Anion-exchange membrane fuel cell (AEMFC) tests revealed that conventional RIG-AEMs and RAFT-AEMs with low RAFT content (5 wt%) have comparable beginning-of-life performances (~0.95 W cm− 2 ). However, for higher RAFT contents, the performance trends to decrease indicating an imbalance in water management. Furthermore, short-term stability tests suggest that RAFT-AEMs are able to operate highly stable, with a conductivity rate loss of 0.05% h− 1 , which represents an improvement of 160% in comparison to conventional RIG-AEM. AFM analysis demonstrated that structural ordering molecular and morphology tailor the fundamental properties of ETFE-based AEMs, combining enhanced performance and stability for alkaline fuel cell applications.

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  • IPEN-DOC 25091

    FAZOLIN, GABRIELA N. ; VARCA, GUSTAVO H.C. ; KADLUBOWSKI, SLAWOMIR; SOWINSKI, SEBASTIAN; LUGAO, ADEMAR B. . The effects of radiation and experimental conditions over papain nanoparticle formation: towards a new generation synthesis. Radiation Physics and Chemistry, v. 169, p. 1-8, 2020. DOI: 10.1016/j.radphyschem.2018.08.033

    Abstract: Papain is a natural enzyme extracted from the fruit of Carica papaya Linnaeus, successfully applied in the pharmaceutical area as a drug carrier and debridement agent for wounds. In recent studies papain nanoparticles were synthesized and crosslinked with the use of ionizing radiation in the search for biopharmaceutical advantages as well as the development of bioactive nanocarriers. This study addresses the effects of buffer molarity and irradiation conditions on papain nanoparticles formation. Nanoparticles were synthesized on ice bath using ethanol (20%, v/v) as a cosolvent and crosslinked by gamma radiation using a 60Co source. Experimental variables included the synthesis in deionized water and in 1, 10, 25 and 50mM phosphate buffer, under different temperatures of −20 °C, 0 °C and 20 °C before and throughout the irradiation period, and using radiation dose rates of 0.8, 2, 5 and 10 kGy h−1 to reach the dose of 10 kGy. Proteolytic activity was quantified using Nα- benzoyl-DL-arginine-p-nitroanilide hydrochloride. Nanoparticle size and crosslinking by means of bityrosine were evaluated by dynamic light scattering and fluorescence measurements, respectively. Buffer molarity and radiation dose rate were identified to influence bityrosine formation and proteolytic activity without impacting nanoparticle size. Variations in temperature impacted bityrosine formation exclusively. Optimized conditions for papain nanoparticle synthesis were achieved using 50mM phosphate buffer at the dose rate of 5 kGy h−1 and temperature of 0 °C throughout the process.

    Palavras-Chave: cobalt 60; cross-linking; dose rates; gamma radiation; irradiation; nanoparticles; papain; radiation doses; synthesis

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  • IPEN-DOC 25876

    MOURA, ESPERIDIANA A.B. . The potential of micro- and nano-sized fillers extracted from agroindustry residues as reinforcements of thermoplastic-based biocomposites: a review. In: IKHMAYIES, SHADIA (Ed.); LI, JIAN (Ed.); VIEIRA, CARLOS M.F. (Ed.); MARGEM, JEAN I. (Ed.); BRAGA, FABIO de O. (Ed.). Green Materials Engineering. Cham, CZ, Switzerland: Springer Nature Switzerland AG, 2019. p. 89-100, (The Minerals, Metals & Materials Series). DOI: 10.1007/978-3-030-10383-5_10

    Abstract: Currently, the relevance of reuse of agroindustrial waste to obtain fillers in micro- and nano-sizes for the development of biocomposite materials has grown significantly. Production processes based on sustainable and low carbon development have increased interest in more environmentally friendly polymer composites, which have made the origin of reinforcement materials a determining factor for their application in this segment. This work presents a review of the developments of our team in the field of thermoplastic biocomposites reinforced with micro- and nano-sized fillers extracted from agroindustry residues. The different residues from Brazilian agroindustry available for the extraction of micro- and nano-sized fillers for the production of polymer biocomposites, the methods of the extraction and treatments of these natural fillers are presented; and its application as reinforcements in thermoplastic-based biocomposite are discussed in this review.

    Palavras-Chave: agriculture; agricultural wastes; environmental impacts; bagasse; biodegradation; thermoplastics; composite materials; fillers; polymers

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  • IPEN-DOC 28073

    FREITAS, LUCAS F. ; FERREIRA, ARYEL H. ; THIPE, VELAPHI C. ; VARCA, GUSTAVO H.C. ; LIMA, CAROLINE S.A. ; BATISTA, JORGE G.S. ; RIELLO, FABIANE N. ; NOGUEIRA, KAMILA ; CRUZ, CASSIA P.C. ; MENDES, GIOVANNA O.A. ; RODRIGUES, ADRIANA S. ; SOUSA, THAYNA S. ; ALVES, VICTORIA M. ; LUGAO, ADEMAR B. . The state of the art of theranostic nanomaterials for lung, breast, and prostate cancers. Nanomaterials, v. 11, n. 10, p. 1-31, 2021. DOI: 10.3390/nano11102579

    Abstract: The synthesis and engineering of nanomaterials offer more robust systems for the treatment of cancer, with technologies that combine therapy with imaging diagnostic tools in the so‐called nanotheranostics. Among the most studied systems, there are quantum dots, liposomes, polymeric nanoparticles, inorganic nanoparticles, magnetic nanoparticles, dendrimers, and gold nanoparticles. Most of the advantages of nanomaterials over the classic anticancer therapies come from their optimal size, which prevents the elimination by the kidneys and enhances their permeation in the tumor due to the abnormal blood vessels present in cancer tissues. Furthermore, the drug delivery and the contrast efficiency for imaging are enhanced, especially due to the increased surface area and the selective accumulation in the desired tissues. This property leads to the reduced drug dose necessary to exert the desired effect and for a longer action within the tumor. Finally, they are made so that there is no degradation into toxic byproducts and have a lower immune response triggering. In this article, we intend to review and discuss the state‐of‐the‐art regarding the use of nanomaterials as therapeutic and diagnostic tools for lung, breast, and prostate cancer, as they are among the most prevalent worldwide.

    Palavras-Chave: nanomaterials; nanotechnology; neoplasms; theranostics

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  • IPEN-DOC 26294

    MASSEI, MARIANA G.R. ; ZAIM, MARCIO H.; MACHADO, LUCI D.B. ; MATHOR, MONICA B. . Thermoplastic polyurethane as biomaterial: study of the modification caused by ionizing radiation. In: INTERNATIONAL NUCLEAR ATLANTIC CONFERENCE, October 21-25, 2019, Santos, SP. Proceedings... Rio de Janeiro: Associação Brasileira de Energia Nuclear, 2019. p. 2598-2608.

    Abstract: New materials are being studied and widely applied in the health area, highlighting biocompatible polymers as the most versatile. Among these polymers, we developed the methodology for the manufacture of Thermoplastic Polyurethane films for application as Biomaterials. The proposed sterilization by ionizing radiation requires the study and characterization of the material to evaluate possible losses or modifications, due to the influence that the radiation can cause in the polymer chains, losing the characteristics for the purpose used. Therefore, the present work evaluates, through chemical and physicochemical characterization, the possible extension of the changes caused by the radiation in the polyurethane film. The material is produced in an environment with controlled temperature and humidity and subjected to increasing doses of gamma (15, 25 and 50 kGy), ethylene oxide and plasma as comparative techniques. The techniques DSC (Differential Scanning Calorimetry) TGA (Thermogravimetry) and FTIR-ATR (Fourier Transform Infrared Spectrometry) have proved that the material, after applied the sterilization techniques, maintains its physical-chemical characteristics and does not suffer any modifications after the treatment.

    Palavras-Chave: biological materials; calorimetry; chemical analysis; cobalt 60; films; fourier transformation; gamma radiation; infrared spectra; polyurethanes; radiation dose units; sterilization; thermoplastics

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  • IPEN-DOC 25837

    ROSA, JORGE M. ; GARCIA, VANESSA S.G. ; BOIANI, NATHALIA F. ; MELO, CAMILA G. ; PEREIRA, MARIA C.C. ; BORRELY, SUELI I. . Toxicity and environmental impacts approached in the dyeing of polyamide, polyester and cotton knits. Journal of Environmental Chemical Engineering, v. 7, n. 2, p. 1-7, 2019. DOI: 10.1016/j.jece.2019.102973

    Abstract: Three colouration process was analyzed, in which consumption of water, the spent of electrical and thermal energy, emission of carbon dioxide besides effluent toxicity of dyeing of polyamide, cotton and polyester knits were approached. the dyeing of polyamide knit presented lowest consumption of electrical energy, the dyeing of polyester knit presented the lowest consumption of thermal energy and emission of co2 molecules into atmosphere, and the effluent of cotton dyeing presented lowest acute toxicity (CE50) to Daphnia similis.

    Palavras-Chave: toxicity; dyes; cotton; textiles; polyamides; polyesters; energy consumption; environmental impacts; water requirements; thermal energy storage equipment; brazil; pollutants; textile industry; waste water; daphnia

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  • IPEN-DOC 28367

    BIANCOLLI, ANA L.G. ; BARBOSA, ANDREY S. ; KODAMA, YASKO ; SOUZA JUNIOR, ROGERIO R. de; LANFREDI, ALEXANDRE J.C.; FONSECA, FABIO C. ; REY, JOSE F.Q.; SANTIAGO, ELISABETE I. . Unveiling the influence of radiation-induced grafting methods on the properties of polyethylene-based anion-exchange membranes for alkaline fuel cells. Journal of Power Sources, v. 512, p. 1-12, 2021. DOI: 10.1016/j.jpowsour.2021.230484

    Abstract: Anion-exchange membranes (AEM) are envisioned as the enabling materials for the widespread use of cost-effective and efficient polymeric fuel cells. Advancing the understanding of the effect of radiation-induced grafting (RIG) method on the final properties of AEMs is crucial to boost the performance of anion-exchange membrane fuel cells (AEMFCs). The present study provides a systematic investigation of the effect of RIG methods on physicochemical properties of LDPE-based AEMs with similar degree of grafting (DoG) and ion exchange capacity (IEC). Samples grafted by two methods − pre-irradiation (PIM) and simultaneous (SM) − have the same molecular structure, but distinct physicochemical properties due to markedly differences in the degree of crosslinking. Detailed characterization of AEMs showed that RIG method determines the mechanical properties, water transport, and the distribution of ionic groups, which have a direct impact on fuel cell performance and durability. The discussed results show that grafting step directly influences the internal structure and morphology. Controlling the synthesis parameters during RIG is a key feature to design AEMs with enhanced properties that lead to high AEMFC performance and stability.

    Palavras-Chave: ion exchange; anions; membranes; fuel cells; irradiation

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  • IPEN-DOC 27893

    SILVA, T.T. ; BORRELY, S.I. . Use of ionizing radiation for the inhibition and removal of cyanotoxins in water: a brief review. Brazilian Journal of Radiation Sciences, v. 9, n. 1A, p. 1-18, 2021. DOI: 10.15392/bjrs.v9i1A.1457

    Abstract: Cyanobacteria are an ancient and diverse group of microorganisms, considered as important contributors to the formation of Earth's atmosphere and nitrogen fixation. However, the input of nutrients in water by anthropogenic activities frequently provides cyanobacteria blooms associated with toxic compounds. Secondary metabolites, also called cyanotoxins, are often harmful to wild and domestic life, including humans. The first part of this review focuses on cyanobacteria and their ability to produce a variety of toxins as well as describe the Brazilian guidelines on the evaluation and management of these toxins in water quality. Then, we present a review of recent literature on the use of ionizing radiation in terms of cyanobacteria cell removal, degree of degradation of cyanotoxins in water, and reaction kinetics. In view of the exposed results, the paper concludes that ionizing radiation is an efficient and economically viable alternative for the remediation of areas contaminated by cyanobacterial blooms and cyanotoxins, especially in reservoirs intended for water treatment and supply. In addition, some suggestions are provided for further studies on the use of this technology in the treatment of drinking water.

    Palavras-Chave: comparative evaluations; cyanobacteria; drinking water; electron beams; gamma radiation; inhibition; radiation doses; removal; toxins; water treatment

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  • IPEN-DOC 27818

    TANGTHONG, THEERANAN; PIROONPAN, THANANCHAI; THIPE, VELAPHI C. ; KHOOBCHANDANI, MENKA; KATTI, KAVITA; KATTI, KATTESH V.; PASANPHAN, WANVIMOL. Water-soluble chitosan conjugated DOTA-bombesin peptide capped gold nanoparticles as a targeted therapeutic agent for prostate cancer. Nanotechnology, Science and Applications, v. 14, p. 69-89, 2021. DOI: 10.2147/NSA.S301942

    Abstract: Introduction: Functionalization of water-soluble chitosan (WSCS) nanocolloids with, gold nanoparticles (AuNPs), and LyslLys3 (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid)-bombesin 1– 14 (DOTA-BBN) peptide affords an innovative pathway to produce prostate tumor cell-specific nanomedicine agents with potential applications in molecular imaging and therapy. Methods: The preparation involves the production and full characterization of water-soluble chitosan (WSCS), via gamma (γ) rays (80 kGy) irradiation, followed by DOTA-BBN conjugation for subsequent use as an effective template toward the synthesis of tumor cell-specific AuNPs-WSCS-DOTA-BBN. Results: The WSCS-DOTA-BBN polymeric nanoparticles (86 ± 2.03 nm) served multiple roles as reducing and stabilizing agents in the overall template synthesis of tumor cell-targeted AuNPs. The AuNPs capped with WSCS and WSCS-DOTA-BBN exhibited average Au-core diameter of 17 ± 8 nm and 20 ± 7 nm with hydrodynamic diameters of 56 ± 1 and 67± 2 nm, respectively. The AuNPs-WSCS-DOTA-BBN showed optimum in vitro stability in biologically relevant solutions. The targeted AuNPs showed selective affinity toward GRP receptors overexpressed in prostate cancer cells (PC-3 and LNCaP). Discussion: The AuNPs-WSCS-DOTA-BBN displayed cytotoxicity effects against PC-3 and LNCaP cancer cells, with concomitant safety toward the HAECs normal cells. The AuNPs-WSCS-DOTA-BBN showed synergistic targeting toward tumor cells with selective cytotoxicity of AuNPs towards PC-3 and LNCaP cells. Our investigations provide compelling evidence that AuNPs functionalized with WSCS-DOTA-BBN is an innovative nanomedicine approach for use in molecular imaging and therapy of GRP receptor-positive tumors. The template synthesis of AuNPs-WSCS-DOTA-BBN serves as an excellent non-radioactive surrogate for the development of the corresponding 198AuNPs theragnostic nanoradiopharmaceutical for use in cancer diagnosis and therapy.

    Palavras-Chave: nanoparticles; gold; prostate; neoplasms; radiopharmaceuticals; therapy; aqueous solutions; chitin

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