JORGE GABRIEL DOS SANTOS BATISTA
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Artigo IPEN-doc 30910 Advances in silver nanoparticles2024 - RODRIGUES, ADRIANA S.; BATISTA, JORGE G.S.; RODRIGUES, MURILO A.V.; THIPE, VELAPHI C.; MINARINI, LUCIENE A.R.; LOPES, PATRICIA S.; LUGAO, ADEMAR B.Nanoparticles play a crucial role in the field of nanotechnology, offering different properties due to their surface area attributed to their small size. Among them, silver nanoparticles (AgNPs) have attracted significant attention due to their antimicrobial properties, with applications that date back from ancient medicinal practices to contemporary commercial products containing ions or silver nanoparticles. AgNPs possess broad-spectrum biocidal potential against bacteria, fungi, viruses, and Mycobacterium, in addition to exhibiting synergistic effects when combined with certain antibiotics. The mechanisms underlying its antimicrobial action include the generation of oxygen-reactive species, damage to DNA, rupture of bacterial cell membranes and inhibition of protein synthesis. Recent studies have highlighted the effectiveness of AgNPs against various clinically relevant bacterial strains through their potential to combat antibiotic-resistant pathogens. This review investigates the proteomic mechanisms by which AgNPs exert their antimicrobial effects, with a special focus on their activity against planktonic bacteria and in biofilms. Furthermore, it discusses the biomedical applications of AgNPs and their potential non-preparation of antibiotic formulations, also addressing the issue of resistance to antibiotics.Capítulo IPEN-doc 30888 Copper-Based Nanomaterials for Biologically Relevant Compounds2024 - BATISTA, JORGE G. dos S.; RODRIGUES, MURILO A.V.; FREITAS, LUCAS F. de; FONSECA, ANA C.M.; RODRIGUES, ADRIANA de S.; CRUZ, CASSIA P.C. da; THIPE, VELAPHI C.; LUGAO, ADEMAR B.Copper-based nanomaterials have emerged as a new platform in various scientific domains due to their unique physicochemical, biological, and compatibility properties. This review explores the multifaceted applications of copper nanomaterials in the areas of biosensing, drug delivery, cancer therapy, and environmental remediation. The innovative role of copper nanomaterials in biosensors and their exceptional sensitivity and specificity in detecting biomolecules are discussed. Moreover, the potential applications of copper-based nanomaterials in drug delivery systems, highlighting the controlled and targeted release of therapeutic agents’ approaches are explored. In the domain of cancer theragnostic, copper nanomaterials exhibit promising results thus offering practical tools for early diagnosis and advanced treatment modalities. Furthermore, the antimicrobial properties of copper nanoparticles are explored, emphasizing their importance in combating microbial threats and promoting a new era in antimicrobial research. Copper-based nanomaterials could have a significant role in environmental and bioremediation applications. The strong catalytic activity of copper nanoparticles makes them ideal candidates for environmental remediation. In summary, this comprehensive review consolidates the latest advances in copper nanomaterials research, providing valuable information for scientists and researchers involved in diverse fields to promote the development of new applications and technologies.Resumo IPEN-doc 30275 Silver nanoparticles reduced by tannic acid and sodium citrate2023 - RODRIGUES, ADRIANA S.; BATISTA, JORGE G.S.; MINARINI, LUCIENE A.R.; LOPES, PATRICIA; LUGAO, ADEMAR B.Introduction and objective: Green nanotechnology aims to reduce hazardous chemical waste in the environment through sustainable development. Phytochemicals are proposed to minimize environmental impacts and produce safe biological applications. Silver nanoparticles (AgNPs) have effective antimicrobial properties against Gram-positive and Gram-negative bacterias, fungi and viruses, being promising to reduce the microbial load. Antimicrobial systems based on AgNPs shows promise in combating bacteria. Methodology: Confirmation of the formation of silver nanoparticles was evaluated by UV-Vis spectrophotometry. The hydrodynamic size and polydispersion index were evaluated by dynamic light scattering. The zeta potential was used to assess stability through surface charge. The obtained morphology and average size were evaluated by transmission electronic microscopy. The cytotoxicity assay was performed to assess cellular viability of silver nanoparticles in HUVEC cells. The antimicrobial activity was analyzed by minimum inhibitory concentration through microdilution in broth and later the inoculum was performed in plates. Results and discussion: Characterization by spectrophotometry of AT_AgNPs and CT_AgNPs showed absorption bands at 430 nm. Hydrodynamic size analyzes revealed diameters of 57.87-97.45 nm, with polydispersion indices (PdI) ranging between 0.289 and 0.392. The zeta potential was determined between - 4.41 and -10.3 mV. Transmission electron microscopy (TEM) images revealed spherical morphology with sizes between 20-50 nm. AgNPs have been tested as a treatment against hospital microorganisms with risk classification level 2, including Gram-negative (Acinetobacter baumannii, Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa) and Gram-positive (Staphylococcus aureus) bacteria. The Minimum Inhibitory Concentration (MIC) was determined to evaluate the lowest concentration that inhibits the growth of microorganisms. The MIC values obtained with the AT_AgNPs were: 4.18 ug/mL (AB14 and EC23), 8.36 ug/mL (EC26 and KP43), 16.72 ug/mL (PA17), 66.9 ug/mL (PA3) and 133.8 ug/mL (SA). For CT_AgNPs, they were: 51.8 ug/mL (AB14, EC26 and PA17), without inhibition in EC23, KP43, PA3 and SA strains. Synergism was evaluated by mixing suspensions of the two nanoparticles (ATCT_AgNPs), resulting in MIC values of 1.48 ug/mL (PA3 and SA), 2.96 ug/mL (EC23, KP43 and PA17) and 5.93 ug/mL (AB14 and EC26). Conclusions: The results suggest that AT_AgNPs and the synergistic combination with CT_AgNPs have potential as effective antimicrobial agents against nosocomial bacteria. These AgNPs may represent a promising alternative for the development of new therapeutic strategies to combat bacterial infections. However, further studies are needed to investigate its activity in other contexts and its safety in clinical use.Tese IPEN-doc 28791 Nanopartículas de ouro para terapia e diagnóstico de câncer utilizando nanotecnologia verde2020 - BATISTA, JORGE G. dos S.As nanopartículas de ouro (AuNPs) vem sendo amplamente estudadas por atenderem às necessidades de sistemas nanocarreadores na terapia e diagnóstico de câncer. Elas podem ser usadas no direcionamento e liberação de fármacos a sítios ou grupos celulares específicos, atuar como radiossensibilizadores e em terapias fototérmicas como agente gerador de calor. Um número significativo de estudos demonstrou suas possíveis aplicações, tais como biossensores, contraste na imagiologia biológica, em sistemas de liberação de fármacos, terapia e diagnóstico do câncer. Assim, as nanopartículas de ouro são consideradas promissoras no desenvolvimento de novos compostos com potencial aplicação na medicina oncológica, no tratamento de inflamações crônicas, infecções, doenças degenerativas e autoimunes. No entanto, apesar das formas nanométricas de ouro apresentarem menor toxicidade comparada aos muitos outros nanomateriais, a toxicidade dessas partículas deve ser minuciosamente avaliada. O maior desafio é propor um método para funcionalizar a superfície das nanopartículas, e assim modular sua farmacocinética e farmacodinâmica, além de atender aos requisitos de toxicidade para aprovação e aplicação de um nanobiomaterial. O objetivo desse estudo foi desenvolver um método de síntese de nanopartículas de ouro (AuNPs) com potencial aplicação como um nanobiomaterial na teranóstica (terapia e diagnóstico) do câncer. Para tanto, foi utilizado o conceito de nanotecnologia verde, em que compostos fitoquímicos com potencial redutor foram utilizados no preparo das AuNPs. Também foi estabelecido um método de funcionalização de AuNPs por recobrimento com albumina do soro bovino e humano utilizando radiação ionizante. A importância do recobrimento com albumina está relacionada a afinidade dessa proteína com os receptores glicoproteicos GP60, que são encontrados em diversas células tumorais, além de contribuir potencialmente com a cinética das nanopartículas de ouro. A caracterização físico-química das AuNPs e a reprodutibilidade do método foi avaliada com base nos ensaios de caracterização realizados pelas técnicas de espectrofotometria UV-Vis/Fluorescência, espalhamento dinâmico de luz (DLS), potencial Zeta, microscopia eletrônica de transmissão (MET), espectroscopia de emissão óptica por plasma acoplado indutivamente (ICP-OES) e eletroforese em gel (SDS-PAGE). A estabilidade foi avaliada em relação à temperatura, pH, concentração de NaCl, PBS, solução contendo aminoácidos e meio de cultura celular DMEM sem e com suplementação de soro fetal bovino. As linhagens celulares utilizadas foram câncer de próstata humano (PC3), adenocarcinoma de mama humano (MDA-MB 231) e células de tecido pulmonar de hamster chinês macho (V79-4). Nas concentrações testadas as AuNPs não apesentaram citotoxicidade in vitro utilizando o método do vermelho neutro e MTT. Para a avaliação preliminar da nanotoxicidade foi realizado o estudo in vivo utilizando o peixe zebra. Nos estudos de internalização in vitro das nanopartículas utilizando as linhagens tumorais MDA-MB 231 e PC3 foi possível verificar qualitativamente a internalização das AuNPs. Os ensaios de radiomarcação das EGCG-AuNPs e EGCG-AuNPs-ASHɣ precisam ser otimizados quanto à estabilidade e pureza radioquímica. A nanotecnologia verde provou ser uma ferramenta valiosa na síntese de nanopartículas de ouro em relação à toxicidade, não exigindo etapas de eliminação de solventes e substâncias potencialmente tóxicas.Artigo IPEN-doc 25206 An overview of the synthesis of gold nanoparticles using radiation technologies2018 - FREITAS, LUCAS F. de; VARCA, GUSTAVO H.C.; BATISTA, JORGE G. dos S.; LUGAO, ADEMAR B.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.