ADRIANA KUCHINSKI CAVALCANTE
4 resultados
Resultados de Busca
Agora exibindo 1 - 4 de 4
Resumo IPEN-doc 28374 Desenvolvimento de nanopartículas de ouro (AuNPs) para teranóstica2021 - RODRIGUES, ADRIANA de S.; LUGAO, ADEMAR B.; BATISTA, JORGE G. dos S.; KUCHINSKI, ADRIANA; FREITAS, LUCAS F. de; CRUZ, CASSIA P.C. daArtigo IPEN-doc 27201 Comparison between gold nanoparticles synthesized by radiolysis and by EGCG-driven gold reduction2020 - 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.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.Resumo IPEN-doc 25384 Radiolytic synthesis of non-toxic, size-homogeneous gold nanoparticles2018 - FREITAS, L.F. de; CAVALCANTE, A.K.; LUGAO, A.B.Radiolytic synthesis of nanoparticles is one of the successful examples of Green Chemistry (the use of non-toxic chemicals, environmentally benign solvents and renewable materials during the chemical processes), in which the reducing agents responsible for the particle nucleation are no other than the reactive species generated by the radiolysis of the solvent itself (i.e. water, acetone or alcohols). This study consists on the radiolytic synthesis and characterization of gold nanoparticles, as well as the assessment of their toxicity levels to Zebrafish embryos (Danio rerio), as an indication of a possible environmental effect. The nanoparticles were synthesized by mixing: NaAuCl4 2 x 10-3 M; polyvinylpyrrolidone 100 kDa 0.5% (as size stabilizer); propan-2-ol 0.2 M and acetone 0.06 M (for the generation of propyl radicals); and AgNO3 6 x 10-5 M (another size stabilizer), followed by 10 kGy of gamma radiation (5 kGy h-1) [1]. The particles were characterized by their absorption spectra in the UV and visible, and the dynamic light scattering (DLS) technique was used to assess their hydrodynamic size. Finally, the impact on the development of Zebrafish embryos was investigated for different dilutions of the nanoparticles suspension, according to the OECD protocol nº 236 (Guideline on Fish Embryo Acute Toxicity Test – FET), as a means of assessing the environmental impact of the nanomaterial. An acute (96 hours of exposition to gold nanoparticles) and a chronic (168 hours of exposition) assay were performed. The particles were successfully synthesized in a multipurpose gamma irradiator, with an absorption peak at 532 nm and a narrow size distribution (around 80 nm). There was no evident toxicity for the fish in any tested concentration, leading to the conclusion that this green method of nanoparticle synthesis generates a potentially environment-safe material, with good control of size and optical properties.Resumo IPEN-doc 25275 Radiolytic synthesis of non-toxic, size-homogeneous gold nanoparticles2018 - FREITAS, L.F.; KUCHINSKI, A.C.; LUGAO, A.B.Radiolytic synthesis of nanoparticles is one of the successful examples of Green Chemistry (the use of non-toxic chemicals, environmentally benign solvents and renewable materials during the chemical processes), in which the reducing agents responsible for the particle nucleation are no other than the reactive species generated by the radiolysis of the solvent itself (i.e. water, acetone or alcohols). This study consists on the radiolytic synthesis and characterization of gold nanoparticles, as well as the assessment of their toxicity levels to Zebrafish embryos (Danio rerio), as an indication of a possible environmental effect. The nanoparticles were synthesized by mixing: NaAuCl4 2 x 10-3 M; polyvinylpyrrolidone 100 kDa 0.5% (as size stabilizer); propan-2-ol 0.2 M and acetone 0.06 M (for the generation of propyl radicals); and AgNO3 6 x 10-5 M (another size stabilizer), followed by 10 kGy of gamma radiation (5 kGy h-1) [1]. The particles were characterized by their absorption spectra in the UV and visible, and the dynamic light scattering (DLS) technique was used to assess their hydrodynamic size. Finally, the impact on the development of Zebrafish embryos was investigated for different dilutions of the nanoparticles suspension, according to the OECD protocol nº 236 (Guideline on Fish Embryo Acute Toxicity Test – FET), as a means of assessing the environmental impact of the nanomaterial. An acute (96 hours of exposition to gold nanoparticles) and a chronic (168 hours of exposition) assay were performed. The particles were successfully synthesized in a nuclear reactor, with an absorption peak at 532 nm and a narrow size distribution (around 25 nm). There was no evident toxicity for the fish in any tested concentration, leading to the conclusion that this green method of nanoparticle synthesis generates a potentially environment-safe material, with good control of size and optical properties.