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Item Zinc pthalocyanine loaded poly (lactic acid) nanoparticles by double emulsion methodology for photodynamic therapy against 9 L/LacZ gliosarcoma cells(Taylor & Francis Group) Oliveira Junior, Benedito Marcio de; Teodoro, Jéssica Beatriz Miranda; Ambrósio, Jéssica Aparecida Ribeiro; Gonçalves, Érika Peterson; Beltrame Junior, Milton; Marcolino, Luciana Maria Cortez; Pinto, Juliana Guerra; Ferreira-Strixino, Juliana; Simioni, Andreza RibeiroDevelopment delivery systems, such as nanoparticles, represent a growing area in biomedical research. Nanoparticles (NP) were prepared using a double-emulsion method to load zinc(II) phthalocyanine (ZnPc). NP were obtained using poly (lactic acid) (PLA). ZnPc is a second generation of photosensitizer used in photodynamic therapy (PDT). ZnPc loaded PLA nanoparticles (NPLAZnPc) were prepared by double-emulsion method, characterized and available in cellular culture. The mean nanoparticle size presented particle size was 384.7 ± 84.2 nm with polydispersity index (PDI) of 0.150 ± 0.015, and the encapsulation efficiency was of 83%. The nanoparticle formulations presented negative zeta potential values (27.5 ± 1.0 mV), explaining their colloidal stability. ZnPc loaded nanoparticles maintain its photophysical behavior after encapsulation. Photosensitizer release from nanoparticles was sustained over 168 h with a biphasic ZnPc release profile. An in vitro phototoxic effect in range of 80% was observed in 9 L/ LacZ gliosarcoma cells at laser light doses (10 J cm2) with 3.0 mg mL1 of NPLA-ZnPc. All the physical–chemical, photophysical and photobiological measurements performed allow us to conclude that ZnPc loaded PLGA nanoparticles is a promising drug deliverysystem for PDT.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, Érika 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 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.