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Item Curcumin-loaded bovine serum albumin (BSA) nanoparticles: photoreactivity and photodynamic action against Acinetobacter baumannii and Staphylococcus aureus(Royal Society of Chemistry) Pinto, Juliana Guerra; Laneri, Francesca; Brambilla, Isabelle de Paula Ribeiro; Azevedo, Maria Clara Barbosa Silva de; Ambrósio, Jéssica Aparecida Ribeiro; Simioni, Andreza Ribeiro; Fraix, Aurore; Sortino, Salvatore; Ferreira-Strixino, JulianaCurcumin (CUR) is a naturally occurring pigment, poorly soluble in water and an object of intense interest due to its multifaceted therapeutic and phototherapeutic activity. In this contribution, bovine serum albumin nanoparticles (BSA-NPs) with oppositely charged surfaces have been used as suitable nanocarriers both to overcome the poor water solubility of CUR and to encourage its interaction with Gram-positive and Gram-negative bacteria. The different surface charges of the BSA-NPs do not affect either the spectroscopic or the photochemical behaviour of the encapsulated CUR which in all cases is almost exclusively present in a diketo form rather than the enolic one. This strictly dictates the response of CUR to blue light excitation which, under these conditions, exhibits the usual reactivity of carbonyl compounds toward molecules that behave as hydrogen donors such as the BSA-NP components. Steady-state and time-resolved photochemical experiments show that the encapsulated CUR under- goes photodecomposition with rate basically independent of the presence of oxygen. The photo- decomposition seems to be mediated mainly by an intermolecular H-abstraction from the components of the nanocarrier by the lowest excited triplet state of CUR with the formation of the corresponding ketyl radical occurring in less than 0.5 ms. This radical is oxidized by molecular oxygen, likely leading to peroxyl and hydroperoxyl radical species, probably responsible for the photodynamic action. Accordingly, with the short triplet lifetime, no singlet oxygen photogeneration is observed. Concentrations of 0.2, 0.3 and 0.4 mM were selected for in vitro tests. Internalization of both formulations was observed in strains of A. baumannii and S. aureus, after 15 minutes of interaction. After irradiation, a reduction in the viability of bacteria was observed, at the different concentrations tested, with concentrations of 0.4 and 0.3 mM being the most efficient.Item Methylene blue functionalized ZnO nanoparticles: a promising approach for photodynamic therapy in the treatment of leishmaniasis(Sage) Gouvea, Thainara Alves; Ambrósio, Jéssica Aparecida Ribeiro; Carvalho, Janicy Arantes; Marmo, Vitor Luca Moura; Marcolino, Luciana Maria Cortez; Pinto, Juliana Guerra; Ferreira-Strixino, Juliana; Simioni, Andreza Ribeiro; Gonçalves, Erika PetersonZinc oxide (ZnO) has wide application in engineering, but its use in medical sciences has aroused growing interest. In this context, ZnO nanoparticles were investigated as vehicles for the delivery of methylene blue (MB), a photosensitizer (PS) used in photodynamic therapy (PDT) against Leishmania braziliensis. ZnO-NPs were produced by a coprecipitation method and characterized by several techniques, including scanning electron microscopy (SEM), UV-VIS spectroscopy, Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). The results showed that the ZnO-NPs presented uniform spheroidal morphology with open porosity, allowing an efficient methylene blue (MB) encapsulation without significant structural changes, ensuring stability and the absence of aggregation. The PS was adsorbed on the porous surface of the ZnO nanoparticles, characterized by scanning electron microscopy (SEM) and steady-state analysis techniques. Spectroscopic analysis confirmed the maintenance of the photosensitizing properties of MB. The biological activity was evaluated in vitro using the trypan blue exclusion method in macrophages infected with Leishmania braziliensis. After loading with the photosensitizer, they maintained their photophysical properties, ensuring the proper location of the dye within the cells. In vitro assays demonstrated the internalization of ZnO/MB-NPs by infected macrophages and a significant reduction in parasite viability after light activation. Thus, the results showed that the developed system exhibits a promising photodynamic activity with relevant therapeutic potential in treating macrophages infected by Leishmania braziliensis.Item Photodynamic therapy of cationic and anionic BSA-curcumin nanoparticles on amastigotes of Leishmania braziliensis and Leishmania major and Leishmania amazonensis(Photodiagnosis and Photodynamic Therapy, Elsevier) Marcolino, Luciana Maria Cortez; Ambrósio, Jéssica Aparecida Ribeiro; Pinto, Juliana Guerra; Ferreira, Isabelle; Simioni, Andreza Ribeiro; Ferreira-Strixino, JulianaCutaneous leishmaniasis is a neglected disease prevalent in tropical countries, and conventional treatment can cause several serious side effects. Photodynamic therapy (PDT) can be considered a promising treatment alternative, as it is non-invasive therapy that has no side effects and uses accessible and low-cost substances, such as curcumin. This study evaluated the PDT response with cationic and anionic BSA nanoparticles encapsulated with curcumin in macrophages infected with L. braziliensis, L. major, and L. amazonensis. The nanoparticle system was characterized using a steady-state technique, scanning electron microscopy (SEM) study, and its biological activity was evaluated using macrophage cell lines infected with different Leishmania species. All spectroscopy measurements demonstrated that BSA curcumin (BSACur) has good photophysical properties, and confocal microscopy shows that macrophages and protozoa internalized the nanoparticles. The viability test demonstrated that at low concentrations, such as 0.1, 0.7, and 1.0 μmol. L 1, there was a decrease in cell viability after PDT application. Furthermore, a decrease in the number of parasites recovered was observed in the PDT groups. The results allowed us to conclude that curcumin loaded into BSA nanoparticles may have potential application in drug delivery systems for PDT protocols, demonstrating reduced cell viability at lower concentrations than free curcumin.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.