TATIANA SANTANA BALOGH
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Resumo IPEN-doc 27654 Influence of argon and nitrous oxide on the synthesis of PVP nanogels prepared by gamma radiation2020 - BALOGH, T.S.; KADLUBOWSKI, S.; BONTURIM, E.; LUGAO, A.B.; VARCA, G.H.Nanogels are innovative systems with great potential for use in chemotherapy, disease diagnosis, release of bioactive substances, vaccines, cell culture systems, biocatalysis, in the generation of bioactive scaffolds in regenerative medicine among other applications. The definition of this material can be directly derived from the definition of polymeric gel, that is, a two-component system consisting of a permanent three-dimensional network of linked polymer chains and solvent molecules filling the pores of this network. Its internal structure is similar to that of hydrogels however presents particle size range varying from 0 to 100 nm leading to several advantages. Nanogel production methods involve intramolecular crosslinking that can be achieved using ionizing radiation. This method avoids the addition of any additives allowing the reaction to be carried out in a pure polymer-solvent system and the production of nanogels for biomedical applications free from monomer and crosslinking agents or surfactants. In this work influence of argon and nitrous oxide on the formation of nanogels by gamma irradiation has been evaluated. The samples were prepared in duplicate in multipurpose cobalt-60 gamma irradiator using a 25 mM PVP solution. Samples were irradiated in argon and nitrous oxide conditions with doses from 1 kGy up to 25 kGy with 10 kGy/h dose rate. These samples were morphologically characterized using Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM) as well as the pristine PVP solution. The mean particle size of the samples and the polydispersity index was performed in equipment Zetasizer Nano ZS - Malvern® and the determination of radius of gyration and molecular weight was performed in equipment Heleos - Wyatt®. It was observed in the conditions evaluated that saturation with argon or nitrous oxide promoted similar results except for 25 kGy dose. At this dose larger mean particle size and radius of gyration were observed in the sample saturated with nitrous oxide.Artigo IPEN-doc 27582 An updated review of macro, micro, and nanostructured hydrogels for biomedical and pharmaceutical applications2020 - 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.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.Resumo IPEN-doc 27327 Synthesis and characterization of PVP nanogels prepared by gamma radiation using 60Co source2019 - BALOGH, T.S.; KADLUBOWSKI, S.; BONTURIM, E.; VARCA, G.; LUGAO, A.B.Nanogels are promising and innovative systems in nanometer scale, with particle size range varying from 0 to 100 nm, of great potential in nanomedicine, pharmaceutics and bionanotechnology. They present several advantages such as capacity of injection into the circulation reaching target tissues and ability to deliver their payloads locally and intracellularly. Nanogels are defined as two-component system on nanometer scale consisting of a permanent three-dimensional network of linked polymer chains, and molecules of a solvent filling the pores of this network. They are formed by intramolecular crosslinking that can be achieved by the use of ionizing radiation, this method allows the formation of nanogels free of additives, rendering them non-toxic, a fundamental requirement for biomedical application. In this work, five samples of nanogels were developed using a 25 mM PVP solution. The samples were saturated with argon and prepared in multipurpose cobalt-60 gamma irradiator using doses of 1, 2, 5, 10 and 25 kGy at a dose rate of 10 kGy/hour corresponding, respectively, to samples A, B, C, D and E. These samples were morphologically characterized using atomic force microscopy (AFM) as well as the pristine PVP solution. The mean particle size of the samples as well as the determination of polydispersity index was performed in equipment Zetasizer Nano ZS - Malvern® and the determination of radius of gyration and molecular weight was realized in equipment Heleos - Wyatt®. The mean particle size of the samples A, B, C, D and E, were, respectively, 41.89, 46.85, 61.04, 62.79 and 62.11 nm and the mean particle size of the pristine PVP solution was 43.28 nm. The AFM results revealed the presence of spherical nanostructures in the samples prepared with dose equal to or more than 5 kGy (samples C, D and E). Under the conditions evaluated in the study the morphological characterization of the nanogels revealed that the doses of 5 kGy, 10 and 25 kGy are the most suitable doses for the nanogel formation as it led to spherical structures when compared to the other conditions assayed.