Navegando por Autor "Pinto, Bruna Cristina dos Santos"
Agora exibindo 1 - 5 de 5
Resultados por página
Opções de Ordenação
Item Desenvolvimento e caracterização de nanopartículas de poli-ԑ-caprolactona contendo cloro-alumínio-ftalocianina para potencial uso na terapia fotodinâmica em células(2022-03-08) Pinto, Bruna Cristina dos Santos; Beltrame Júnior, Milton; Gonçalves, Érika Peterson; Liu, Yao Cho; Naal, Rose Mary Zumstein Georgetto; Rosseti, Isabela Bueno; Simioni, Andreza Ribeiro; São José dos CamposNeste trabalho, nanopartículas do polímero poli-ԑ-caprolactona (PCL) foram desenvolvidas para encapsular a cloro-alumínio ftalocianina (ClAlPc), como modelo fotossensibilizador para aplicação em terapia fotodinâmica (TFD). O método de nanoprecipitação foi aplicado para produzir nanopartículas de PCL-ClAlPc que foram caracterizadas por medidas no estado estacionário, tamanho de partícula, potencial zeta, espalhamento dinâmico de luz, morfologia e eficiência de carregamento. A análise da microscopia eletrônica de varredura (MEV) mostra claramente a formação de nanopartículas uniformes, de formato esférico, com superfície regular e lisa. O tamanho médio das nanopartículas apresentadas foi de 266,7 ± 83,1 nm com índice de polidispersidade (PDI) de 0,105 nm e com a eficiência de encapsulamento de 81,8%. As formulações de nanopartículas apresentaram valores de potencial zeta negativos (-28,31 ± 1,25 mV), explicando sua estabilidade coloidal. O perfil espectral de absorção mostrou que o fotossensibilizador carregado nas nanopartículas não sofre alteração em suas propriedades fotofísicas após o processo de encapsulamento. A ClAlPc encapsulada nas nanopartículas poliméricas apresentou estabilidade física adequada, boas propriedades fotofísicas e fotoquímicas demonstrando a eficiência do carregamento do fármaco. O estudo de liberação de drogas in vitro constatou uma taxa de liberação inicial de forma sustentada e eficiente, típica para os medicamentos carregados nas nanopartículas de PCL. A biocompatibilidade e o efeito fotodinâmico das nanopartículas de PCL-ClAlPc foram avaliados por experimentos in vitro utilizando a linhagem celular HeLa CCL-2, adenorcarcinoma, como modelo biológico. Os estudos mostraram que o sistema não é citotóxico no escuro, mas possuem uma fototoxicidade significativa a 3 μmol.L-1 de concentração de fotossensibilizador encapsulado e 10J.cm-2 de luz, mostrando, nestas condições, diminuição de sobrevida maior que 95%. A localização intracelular demonstrou que as nanopartículas encapsuladas com a cloro- alumínio ftalocianina podem ser internalizadas nas células de adenocarcinoma de maneira efetiva. Com isso, os resultados permitem reforçar a proposta de que as nanopartículas de PCL encapsuladas com ClAlPc é um sistema promissor para o uso em protocolos de aplicação em TFD.Item Synthesis and characterization of photosensitive gelatin-based hydrogels for photodynamic therapy in HeLa-CCL2 cell line(Elsevier) Ambrósio, Jéssica Aparecida Ribeiro; Pinto, Bruna Cristina dos Santos; Marmo, Vitor Luca Moura; Santos, Kennedy Wallace dos; Beltrame Junior, Milton; Pinto, Juliana Guerra; Ferreira-Strixino, Juliana; Raniero, Leandro José; Simioni, Andreza RibeiroBackground: Hydrogel systems are increasingly gaining visibility involving biomedicine, tissue engineering, environmental treatments, and drug delivery systems. These systems have a three-dimensional network composition and high-water absorption capacity, are biocompatible, allowing them to become an option as photosensitizer carriers (PS) for applications in Photodynamic Therapy (PDT) protocols. Methods: A nanohydrogel system (NAHI), encapsulated with chloroaluminium phthalocyanine (ClAlPc) was synthesized for drug delivery.. NAHI was synthesized using gelatin as based polymer by the chemical cross-linking technique. The drug was encapsulated by immersing the hydrogel in a 1.0 mg.mL 1 ClAlPc solution. The external morphology of NAHI was examined by scanning electron microscopy (SEM). The degree of swelling of the synthesized system was evaluated to determine the water absorption potential. The produced nanohydrogel system was characterized by photochemical, photophysical and photobiologial studies. Results: The images from the SEM analysis showed the presence of three-dimensional networks in the formulation. The swelling test demonstrated that the nanohydrogel freeze-drying process increases its water holding capacity. All spectroscopic results showed excellent photophysical parameters of the drug studied when served in the NAHI system. The incorporation efficiency was 70%. The results of trypan blue exclusion test have shown significant reduction (p < 0.05) in the cell viability for all groups treated with PDT, in all concentrations tested. In HeLa cells, PDT mediated by 0,5 mg.mL 1 ClAlPc encapsulated in NAHI showed a decrease in survival close to 95%. In the internalization cell study was possible to observe the internalization of phthalocyanine after one hour of incubation, at 37 ◦C, with the the accumulation of PS in the cytoplasm and inside the nucleus at both concentrations tested. Conclusions: Given the peculiar performance of the selected system, the resulting nanohydrogel is a versatile platform and display potential applications as controlled delivery systems of photosensitizer for photodynamic therapy application.Item Synthesis, characterization, and evaluation of chloroaluminium phthalocyanine incorporated in poly(ε-caprolactone) nanoparticles for photodynamic therapy(Elsevier) Pinto, Bruna Cristina dos Santos; Ambrósio, Jéssica Aparecida Ribeiro; Marmo, Vitor Luca Moura; Pinto, Juliana Guerra; Raniero, Leandro José; Ferreira-Strixino, Juliana; Simioni, Andreza Ribeiro; Beltrame Junior, MiltonBackground: The use of nanotechnology has been widely used in biomedical science, including orthopedic implants, tissue engineering, cancer therapy and drug elution from nanoparticle systems, such as poly-caprolactone (PCL) nanoparticles, which stand out mainly for their biocompatibility, being considered as effective carriers for photosensitizing drugs (PS) in photodynamic therapy (PDT) protocols. Methods: This manuscript describes the synthesis and characterization of PCL nanoparticles for controlled release of the drug chloro-aluminum phthalocyanine (ClAlPc) as a photosensitizer for application in PDT. The PCL-ClAlPc nanoparticles were developed by the nanoprecipitation process. The structure and morphology of the nanoparticles were studied with scanning electron microscopy (SEM) and with Fourier transform infrared (FTIR). The size of nanomaterials was studied using the Dynamic Light Scattering (DLS) method. Photophysical and photochemical characterizations were performed. Subsequently, photobiological studies were also used to characterize the system. Results: The nanoparticles had an average diameter of 384.7 ± 138.6 nm and a polydispersity index of 0.153. SEM analysis revealed that the system formed a spherical shape typical of these delivery systems. Charging efficiency was 82.1% ± 1.2%. The phthalocyanine-loaded PCL nanoparticles maintained their photophysical behavior after encapsulation. Cell viability was determined after the dark toxicity test, and it was possible to observe that there was no evidence of toxicity in the dark, for all concentrations tested. The assay also revealed that adenocarcinoma cells treated with free ClAlPc and in the nanoformulation showed 100% cell death when subjected to PDT protocols. The intracellular location of the photosensitizer indicated a high potential for accumulation in the cytoplasm and nucleus. Conclusions: From the photophysical, photochemical and photobiological analyzes obtained, it was possible to observe that the development of PCL nanoparticles encapsulated with ClAlPc, by the nanoprecipitation method was adequate and that the in vivo release study is efficient to reduce the release rate and attenuate the burst of PS loaded on PCL nanoparticles. The results reinforce that the use of this system as drug delivery systems is useful in PDT protocols.Item Vaterite submicron particles designed for photodynamic therapy in cells(Elsevier) Souza, Eliane de Fátima; Ambrósio, Jéssica Aparecida Ribeiro; Pinto, Bruna Cristina dos Santos; Beltrame Junior, Milton; Sakane, Kumiko Koibuchi; Pinto, Juliana Guerra; Ferreira-Strixino, Juliana; Gonçalves, Érica Peterson; Simioni, Andreza RibeiroBackground: Calcium carbonate (CaCO3) is one of the most abundant materials in the world. It has several different crystalline phases as present in the minerals: calcite, aragonite and vaterite, which are anhydrous crystalline polymorphs. Regarding the preparation of these microparticles, the most important aspect is the control of the polymorphism, particle size and material morphology. This study aimed to develop porous microparticles of calcium carbonate in the vaterite phase for the encapsulation of chloro-aluminum phthalocyanine (ClAlPc) as a photosensitizer (PS) for application in Photodynamic Therapy (TFD). Methods: In this study, spherical vaterite composed of microparticles are synthesized by precipitation route assisted by polycarboxylate superplasticizer (PSS). The calcium carbonate was prepared by reacting a mixed solution of Na2CO3 with a CaCl2 solution at an ambient temperature, 25 °C, in the presence of polycarboxylate superplasticizer as a stabilizer. The photosensitizer was incorporated by adsorption technique in the CaCO3 microparticles. The CaCO3 microparticles were studied by scanning electron microscopy, steady-state, and their biological activity was evaluated using in vitro cancer cell lines by trypan blue exclusion method. The intracellular localization of ClAlPc was examined by confocal microscopy. Results: The CaCO3 microparticles obtained are uniform and homogeneously sized, non-aggregated, and highly porous microparticles. The calcium carbonate microparticles show an average size of 3 μm average pore size of about 30–40 nm. The phthalocyanine derivative loaded-microparticles maintained their photophysical behavior after encapsulation. The captured carriers have provided dye localization inside cells. The in vitro experiments with ClAlPc-loaded CaCO3 microparticles showed that the system is not cytotoxic in darkness, but exhibits a substantial phototoxicity at 3 μmol.L−1 of photosensitizer concentration and 10 J.cm-2 of light. These conditions are sufficient to kill about 80 % of the cells. Conclusions: All the performed physical–chemical, photophysical, and photobiological measurements indicated that the phthalocyanine-loaded CaCO3 microparticles are a promising drug delivery system for photodynamic therapy and photoprocesses.Item Zinc phthalocyanine tetrasulfonate-loaded polyelectrolytic PLGA nanoparticles for photodynamic therapy applications(Elsevier) Toledo, Maria Cristina Modesto Clementino de; Abreu, Alexandro da Silva; Carvalho, Janicy Arantes; Ambrósio, Jéssica Aparecida Ribeiro; Godoy, Daniele da Silva; Pinto, Bruna Cristina dos Santos; Beltrame Junior, Milton; Simioni, Andreza RibeiroBackground: Photodynamic Therapy (PDT) is a modality for the treatment of neoplastic tissues, which is based on the administration of a phototherapeutic agent and light irradiation at an appropriate wavelength, aiming to locate and destroy the target cell with the formation of reactive oxygen species. Nanoencapsulation technology presents itself as a tool for incorporation of bioactive substances aiming to improve their solubility in physiological environment, obtain a longer circulation time in the organism, administration of lower dosages and the minimization of side effects. The present work aimed at the development of poly (lactic acid-glycolic acid) (PLGA) nanoparticles coated with polyelectrolyte film layers for encapsulating zinc phthalocyanine tetrasulfonated (ZnPcSO4) as a bioactive substance model. Methods: PLGA nanoparticles were produced by the double emulsion/solvent evaporation technique and polyelectrolytic coating was performed using polyalkylamine hydrochloride (PAH) as a weak polycation and poly (4- styrene sulfonate) (PSS) as a strong polyanion by layer-by-layer self-assembly technique (known as layer-by-layer-LbL). The nanoparticulate system was studied by scanning electron microscopy, steady-state, and their biological activity was evaluated using in vitro cancer cell lines by classical MTT assay. Results: The polyelectrolytic PLGA nanoparticles had an average diameter of 384.7 ± 138.6 nm, restricted distribution size with a polydispersity index. The obvious change in zeta potential indicates successful alternation in polycation (PAH) and polyanion (PSS) deposition directly in PLGA nanoparticles. Scanning electron microscopy (SEM) analysis showed that the formed system had morphology spherical, typical of these release systems. The loading efficiency was 82.1 % ± 1.2 %. The polyelectrolytic nanoparticles loaded with phthalocyanine maintained their photophysical behavior after encapsulation. Cell viability was determined, obtaining 90 % cell death. Conclusions: Therefore, the presented work depicts ZnPcSO4-loaded polyelectrolytic PLGA nanoparticles as a promise drug delivery system for phototherapeutic agent, which are thus expected to have superior therapeutic efficiency than free drug.