INSTITUTO DE PESQUISAS ENERGÉTICAS E NUCLEARES
Repositório Digital da Produção Técnico Científica

BibliotecaTerezine Arantes Ferraz

Navegação Periódicos - Artigos por Agências de fomento "International Atomic Energy Agency (IAEA)"

Navegação Periódicos - Artigos por Agências de fomento "International Atomic Energy Agency (IAEA)"

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  • IPEN-DOC 26393

    FERREIRA, EDUARDO G.A. ; MARUMO, JULIO T. ; FRANCO, MARGARETH K.K.D. ; YOKAICHIYA, FABIANO; VICENTE, ROBERTO . 10000 years cement: Can hydrated cement last as much as long-lived radionuclides?. Cement and Concrete Composites, v. 103, p. 339-352, 2019. DOI: 10.1016/j.cemconcomp.2019.05.016

    Abstract: This review is focused on the long-term performance of cementitious materials in a repository for radioactive waste. During the last few years, the disposal of disused sealed radioactive sources (DSRS) in a borehole type repository has been studied by many countries. The borehole concept is particularly useful to dispose of spent nuclear fuel and DSRS. In boreholes for DSRS, cementitious materials are intended to be used as structural material, immobilization matrix and as backfill. The understanding of the performance of these materials is essential to ensure the safety of the facilities during their required lifetime, from centuries to many thousands of years, depending on the initial activity and half-life of the waste. This review approaches the behavior of the cement from the hydration and hardening to the long-term processes that can affect its durability. Three main causes of failure of repository-engineered barriers are recognized: a) the formation of a preferential pathway for the migration of the contained radionuclides to the biosphere; b) loss of resistance and cohesion of the structural cementitious material; and c) the increase in the corrosion processes of the metallic components of the structures that affect the overall containment of the facility.

    Palavras-Chave: cements; cement industry; portland cement; radioactive wastes; geologic formations; underground disposal; performance; chemical composition; mineralogy; radiations; magnetic fields; hydration

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  • IPEN-DOC 25206

    FREITAS, LUCAS F. de ; VARCA, GUSTAVO H.C. ; BATISTA, JORGE G. dos S. ; LUGAO, ADEMAR B. . An overview of the synthesis of gold nanoparticles using radiation technologies. Nanomaterials, v. 8, n. 11, 2018. DOI: 10.3390/nano8110939

    Abstract: At a nano-level, optical properties of gold are unique and gave birth to an emerging platform of nanogold-based systems for diverse applications, because gold nanoparticle properties are tunable as a function of size and shape. Within the available techniques for the synthesis of gold nanoparticles, the radiolytic synthesis allows proper control of the nucleation process without the need for reducing agents, in a single step, combined or not with simultaneous sterilization. This review details and summarizes the use of radiation technologies for the synthesis and preparation of gold nanoparticles concerning fundamental aspects, mechanism, current pathways for synthesis and radiation sources, as well as briefly outlines final applications and some toxicity aspects related to nanogold-based systems.

    Palavras-Chave: gold; nanoparticles; gamma radiation; electron beams; x-ray sources; radiolysis; nanotechnology; medicine; diagnostic uses; ionizing radiations

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  • IPEN-DOC 27582

    LIMA, CAROLINE S.A. de ; BALOGH, TATIANA S. ; VARCA, JUSTINE P.R.O. ; VARCA, GUSTAVO H.C. ; LUGAO, ADEMAR B. ; CAMACHO-CRUZ, LUIS A.; BUCIO, EMILIO; KADLUBOWSKI, SLAWOMIR S.. An updated review of macro, micro, and nanostructured hydrogels for biomedical and pharmaceutical applications. Pharmaceutics, v. 12, n. 10, p. 1-28, 2020. DOI: 10.3390/pharmaceutics12100970

    Abstract: Hydrogels are materials with wide applications in several fields, including the biomedical and pharmaceutical industries. Their properties such as the capacity of absorbing great amounts of aqueous solutions without losing shape and mechanical properties, as well as loading drugs of different nature, including hydrophobic ones and biomolecules, give an idea of their versatility and promising demand. As they have been explored in a great number of studies for years, many routes of synthesis have been developed, especially for chemical/permanent hydrogels. In the same way, stimuli-responsive hydrogels, also known as intelligent materials, have been explored too, enhancing the regulation of properties such as targeting and drug release. By controlling the particle size, hydrogel on the micro- and nanoscale have been studied likewise and have increased, even more, the possibilities for applications of the so-called XXI century materials. In this paper, we aimed to produce an overview of the recent studies concerning methods of synthesis, biomedical, and pharmaceutical applications of macro-, micro, and nanogels.

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  • IPEN-DOC 27201

    FREITAS, LUCAS F. de ; CRUZ, CASSIA P.C. da; CAVALCANTE, ADRIANA K. ; BATISTA, JORGE G. dos S. ; VARCA, GUSTAVO H.C. ; MATHOR, MONICA B. ; LUGAO, ADEMAR B. . Comparison between gold nanoparticles synthesized by radiolysis and by EGCG-driven gold reduction. Radiation Physics and Chemistry, v. 174, p. 1-9, 2020. DOI: 10.1016/j.radphyschem.2020.108959

    Abstract: Radiolytic synthesis and phytochemical-driven gold reduction for the generation of nanoparticles are successful examples of Green Chemistry applied for nanomaterials. The present work compares these two green approaches focusing on hydrodynamic size, stability over time, optical properties and toxicity in NIH 3T3 (ATCC® CRL- 1658™) cells and Danio rerio (Zebra Fish). The radiolytic synthesis was performed by mixing 1 mM NaAuCl4; polyvinyl pyrrolidone 0.5%, AgNO3 6×10−5 M, propan-2-ol 0.2 M and acetone 0.06 M, followed by irradiation at 15 kGy (5 kGy h−1, 60Co source). The EGCG-functionalized nanoparticles were synthesized by mixing 1.6 mM of Au with 0.8 mM of EGCG in phosphate buffer (10 mM) for 2 h. Both methods yield the formation of gold nanoparticles featuring plasmon resonance bands at 520–530 nm, polydispersity above 0.3 was relevant only for the radiolytic protocol. Regarding stability over time, after 30 days, the nanoparticles synthesized radiolytically presented no relevant size changes, while some aggregation was observed for the EGCG-particles. The same nanoparticles demonstrated a lack of stability in high ionic strength medium. Slight toxicity was observed for the EGCG-nanoparticles in Danio rerio, with an IC50 calculated as 40.49%, while no IC50 was established within the concentration range of radiolysis-AuNPs used in this study. In conclusion, both green methods generated nanoparticles with good control of size and optical properties, especially via reduction by EGCG. However, the stability and toxicity results were found to be more promising for the radiolytically synthesized gold nanoparticles.

    Palavras-Chave: gold; nanoparticles; synthesis; chemistry; ecology; polyphenols; fishes

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  • IPEN-DOC 25801

    TAPPIZ, B. ; MOREIRA, E.G. . Neutron activation analysis characterization procedures for fish consumed at São Paulo city. Brazilian Journal of Radiation Sciences, v. 7, n. 2A, p. 1-9, 2019. DOI: 10.15392/bjrs.v7i2A.710

    Abstract: The characterization of edible tissues of fishes consumed by humans is very important for determination of sev-eral toxic and potentially toxic elements, ensuring the food safety. The Instrumental Neutron Activation Analysis (INAA) comparative method allows the determination of several of these elements, as well as others, for example of nutritional character. This study is part of an International Atomic Energy Agency (IAEA) technical coopera-tion project of Latin America and Caribbean countries to ensure the quality of food and biomonitoring of con-taminants in shellfish and fishes. Ten specimens of 4 of the most consumed fish in São Paulo city: whitemouth croaker (Micropogonias Furnieri), smooth weakfish (Cynoscion learchus), common snook (Centropomus undeci-malis) and Brazilian sardine (Sardinella brasiliensis) were analyzed. Complete procedures for analysis, which includes purchase in the largest warehouse in Latin America, transport to the laboratory, storage, freeze-drying, milling, weighting and others preparations of the subsamples, and the short irradiation parameters for the de-termination of Br, Cl, K, Mg, Mn and Na are reported. Results obtained under the same irradiation conditions for reference materials (oyster and mussel tissues) for macro and microelements are presented and are in agreement with their certificates, which indicate that the performed analyses were appropriate. Regarding to the mass fraction values obtained for the fish samples, they were in agreement with the literature.

    Palavras-Chave: neutron activation analysis; fishes; brazil; contamination; gamma spectroscopy; quality assurance; quality management; high-purity ge detectors; radioisotopes; food; quality control

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  • IPEN-DOC 27362

    SOUZA, CARLA D. de ; ZEITUNI, CARLOS A. ; FEHER, ANSELMO ; MOURA, JOÃO A. ; COSTA, OSVALDO L. da ; ANGELOCCI, LUCAS V. ; ROSTELATO, MARIA E.C.M. . New core configuration for the fabrication of 125I radioactive sources for cancer treatment. Applied Radiation and Isotopes, v. 165, p. 1-8, 2020. DOI: 10.1016/j.apradiso.2020.109307

    Abstract: In order to provide prostate brachytherapy treatment for more Brazilian men, IPEN is building a laboratory for the manufacture of radioactive sources. The new methodology for the production of iodine-125 seeds with yield 71.7% ± 5.3%. Points of importance were evaluated/discussed: photo-sensibility, reaction vial type, the substitution for iodine-131, pH, and solution volume. The surface was analyzed by FTIR and EDS. At the end, a Monte Carlo-MCNP6 simulation was performed to evaluate the TG-43 parameters.

    Palavras-Chave: radiation sources; iodine 125; brachytherapy; radiation chemistry; monte carlo method; neoplasms; tumor cells; prostate; iodination

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  • IPEN-DOC 24774

    PEREIRA, MARCO A.S. ; PUGLIESI, REYNALDO . Penetration of the consolidant Paraloid (R) B-72 in Macuxi indigenous ceramic vessels investigated by neutron tomography. Nuclear Instruments and Methods in Physics Research, A, v. 889, p. 118-121, 2018. DOI: 10.1016/j.nima.2018.02.034

    Abstract: The neutron tomography technique was applied in studying the penetration of the consolidant Paraloid (R) B-72 in contemporary indigenous ceramic vessels. The study was carried out for two distinct and controlled air humidity conditions, 40% and 90%, in which the vessels were exposed, before the consolidant application. The obtained images have proved that the penetration of Paraloid (R) B-72 in the ceramic does not depend on the humidity condition in which it was applied, moreover allowed a macro-visualization of the consolidant penetration in the ceramic vessel. As the vessels used in the present work were manufactured by an indigenous artisan, Macuxi, according to the same procedures and raw materials used by the ancient artisans, the results obtained can be used as a guide to assist experts, both in the study of archeological objects of Macuxi origin, as well as other objects that had been made by other tribes that lived in the same Amazon region, in Brazil.

    Palavras-Chave: neutrons; tomography; ceramics; biological recovery; cultural objects; humidity control; resins; indigenous peoples; brazil

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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 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.

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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 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 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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1. Portaria IPEN-CNEN/SP nº 387, que estabeleceu os princípios que nortearam a criação do RDI, clique aqui.


2. A experiência do Instituto de Pesquisas Energéticas e Nucleares (IPEN-CNEN/SP) na criação de um Repositório Digital Institucional – RDI, clique aqui.