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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 GMEH - Software de Gerenciamento de Manutenção de Equipamentos Hospitalares(2021-12-17) Ferraz, William de Carvalho; Castilho, Maiara Lima; Raniero, Leandro José; Ferreira, Hélio Lourenço EsperidiãoItem Gold nanoparticles conjugated with epidermal growth factor and gadolinium for precision delivery of contrast agents in magnetic resonance imaging(Springer-Verlag London Ltd.) Queiroz, Marinho de; Veriato, Thaís da Silva; Raniero, Leandro José; Castilho, Maiara LimaThe utilization of contrast agents in magnetic resonance imaging (MRI) has become increasingly important in clinical diagnosis. However, the low diagnostic specificity of this technique is a limiting factor for the early detection of tumors. To develop a new contrast agent with a specific target for early stage tumors, we present the synthesis and characterization of a nanocontrast composed of gold nanoparticles (AuNPs), gadopentetic acid (Gd-DTPA), and epidermal growth factor (EGF). Carbodiimide-based chemistry was utilized to modify Gd-DTPA for functionalization with AuNPs. This resulted in the formation of the Au@Gd-EGF nanocontrast. The relaxation rate (1/T1) of the nanocontrast was analyzed using MRI, and cytotoxicity was determined based on cell viability and mitochondrial activity in a human breast adenocarcinoma cell line. Fourier-transform infrared spectroscopy analysis confirmed the effectiveness of carbodiimide in the formation of the Gd-DTPA-cysteamine complex in the presence of bands at 930, 1042, 1232, 1588, and 1716 cm-1. The complexes exhibited good interactions with the AuNPs. However, the signal intensity of the Au@Gd-EGF nanocontrast was lower than that of the commercial contrast agent because the r1/r2 relaxivities of the Gd-DTPA-based contrast agents were lower than those of the gadoversetamide-based molecules. The Au@Gd-EGF nanocontrast agent exhibited good biocompatibility, low cytotoxicity, and high signal intensity in MRI with active targeted delivery, suggesting significant potential for future applications in the early diagnosis of tumors.Item Uso de templates de vaterita na síntese de microesferas de hidroxiapatita por método hidrotérmico(2022) Ambrósio, Jéssica Aparecida Ribeiro; Gonçalves, Camilli Albernaz; Gonçalves, Érika Peterson; Raniero, Leandro José; Beltrame Junior, Milton; Simioni, Andreza RibeiroItem Hydroxyapatite microspheres used as a drug delivery system for gliosarcoma strain 9l/Lacz treatment by photodynamic therapy protocols(Elsevier) Ambrósio, Jéssica Aparecida Ribeiro; Marmo, Vitor Luca Moura; Gonçalves, Érika Peterson; Pinto, Juliana Guerra; Ferreira-Strixino, Juliana; Raniero, Leandro José; Beltrame Junior, Milton; Simioni, Andreza RibeiroBackground: Hydroxyapatite (HAp) presents similarities with the human bone structure and presents properties such as biodegradability, biocompatibility, and osteoconductivity, which favors its use in prostheses implants and enables its use as a vehicle for the delivery of photosensitizers (PS) from systems of release (DDS) for photodynamic therapy applications Methods: In this work was to synthesized hydroxyapatite microspheres (meHAp), encapsulated with chloroaluminium phthalocyanine (ClAlPc), for DDS. meHAp was synthesized using vaterite as a template. The drug was encapsulated by mixing meHAp and a 50.0 mg.mL− 1 ClAlPc solution. Photochemical, photophysical, and photobiological studies characterized the system. Results: The images from the SEM analysis showed the spherical form of the particles. All spectroscopic results showed excellent photophysical parameters of the drug studied when served in the meHAp system. The incorporation efficiency was 57.8 %. The trypan blue exclusion test results showed a significant reduction (p < 0.05) in cell viability for the groups treated with PDT at all concentrations above 250 μg.mL− 1 . In 9 L/lacZ gliosarcoma cells, PDT mediated at concentrations from 250 to 62.5 µg.mL− 1 reduced cell viability by more than 98 %. In the cell internalization study, it was possible to observe the internalization of phthalocyanines at 37 ◦C, with the accumulation of PS in the cytoplasm and inside the nucleus in the two tested concentrations. Conclusions: From all the results presented throughout the article, the meHAp system shows promise for use as a modified release system (DSD) in photodynamic therapy.Item Vaterite microparticle-loaded methylene blue for photodynamic activity in macrophages infected with Leishmania braziliensis(Springer Nature) Marmo, Vitor Luca Moura; Ambrósio, Jéssica Aparecida Ribeiro; Gonçalves, Érika Peterson; Raniero, Leandro José; Beltrame Junior, Milton; Pinto, Juliana Guerra; Ferreira-Strixino, Juliana; Simioni, Andreza RibeiroCalcium carbonate (CaCO3) exhibits a variety of crystalline phases, including the anhydrous crystalline polymorphs calcite, aragonite, and vaterite. Developing porous calcium carbonate microparticles in the vaterite phase for the encapsulation of methylene blue (MB) as a photosensitizer (PS) for use in photodynamic therapy (PDT) was the goal of this investigation. Using an adsorption approach, the PS was integrated into the CaCO3 microparticles. The vaterite microparticles were characterized by scanning electron microscopy (SEM) and steady-state techniques. The trypan blue exclusion method was used to measure the biological activity of macrophages infected with Leishmania braziliensis in vitro. The vaterite microparticles produced are highly porous, non-aggregated, and uniform in size. After encapsulation, the MB-loaded microparticles kept their photophysical characteristics. The carriers that were captured allowed for dye localization inside the cells. The results obtained in this study indicated that the MB-loaded vaterite microparticles show promising photodynamic activity in macrophages infected with Leishmania braziliensis.Item Calcium Aluminate Cement Blends Containing Bioactive Glass and Strontium for Biomaterial Applications(SciELO) Barbosa, Ana Margarida; Santos, Kennedy Wallace dos; Gonçalves, Irene S.; Leite, Priscila Maria Sarmeiro Corrêa Marciano; Martorano, Antonio Secco; Grisote, Gabriela; Raucci, Larissa Moreira Spinola de Castro; Oliveira, Paulo Tambasco de; Raniero, Leandro José; Oliveira, Ivone Regina deIn this work blends based on calcium aluminate cement (CAC) containing bioactive glass (BG) (5, 7.5 and 10 wt%) and strontium oxide (1 wt%) were produced aiming improve their bioactivity and the capacity to stimulate the bone regeneration. In the first part, the blends containing only BG were characterized as theoretical density, microhardness, uniaxial cold crush strength after SBF and apparent porosity and pore size distribution before and after SBF treatment. In the second part, bioactivity and cell culture tests were also conducted in the blends containing BG and strontium oxide. The addition of 7.5 wt% of BG in homogeneous calcium aluminate cement (CH) improved its mechanical properties as microhardness and uniaxial cold crushing strength. The blends were more bioactive due to the presence of a highly soluble amorphous phase as confirmed by means of SEM/EDX mainly for 7.5 wt% BG without and with Sr from 1 day in SBF. FTIR analyses indicated the formation the apatite-like phase by means of increase of intensity of the PO43- peaks after SBF treatment. All blends allowed the development of the osteoblastic phenotype and the formation of mineralized matrix increased due to the inclusion of BG and Sr promoting the osteogenesis process.Item Síntese e Caracterização de Lipossomas(2024) Melo, Josué David Gimenez de; Tosato, Maira Gaspar; Raniero, Leandro JoséItem SERS-active substrates using DVD-R coated in silver thin films: A preliminary study for detection of commercial glyphosate(Elsevier) Murcia-Correa, Luz Stefany; Usuriaga, Omar; Vieira, Lucia; Raniero, Leandro JoséGlyphosate (GLP) is the herbicide with the highest level of global commercialization and historical use. Even though numerous studies have found this substance to be harmless, current research demonstrates that GLP might affect human health. For this reason, researcher efforts are concentrating on alternatives for analytical quantification, such as Surface Enhanced Raman Spectroscopy (SERS). In this work, a DVD-R@AgNPs SERS substrate was produced by the Cathodic Cage Plasma Deposition (CCPD) technique, which allowed a thin film layer deposition of silver nanoparticles (AgNPs) on the PC grating structure from Digital Video/Versatile Disc Recordable (DVD-R). Scanning Electron Microscopy with energy-dispersive X-ray spectroscopy was used to characterize the substrate and chemical changes on the surface after AgNPs deposition. The DVD-R@AgNPs substrate was used to detect standard crystal violet (CV), GLP, and RoundupTM GLP (GLP-RU) using Raman Spectroscopy. The CV was used as a control sample for SERS measurement, allowing the calculation of the substrate enhancement factor, which was in the order of ∼ 105. To evaluate the efficiency of the SERS substrate, the limit of detection was calculated and showed values of ∼ 10-10 mol/L for CV, 10-7 and 10-8 mol/L for GLP, and 10-6 mol/L for GLP-RU. Thus, the DVD-R@AgNPs SERS sensor is a low-cost substrate that analyzes traces of pesticides such as commercial GLP, demonstrating high SERS sensitivities and many applications.
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