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Carine Zuglianello Diego Fontana De Andrade Paula dos Santos Chaves Lucas Almeida Rigo Adriana Raffin Pohlmann Silvia Stanisçuaski Guterres 《Soft Materials》2018,16(1):20-30
This study proposes a novel blend of drying adjuvants (lactose and polyvinylpyrrolidone) as an approach to produce dispersible powders containing nanocapsules for the development of skin delivery systems. Hydrogels were produced with liquid nanocapsules and spray-dried powders. Nanoparticle recovery was obtained after powder aqueous redispersion. No influence of the intermediate product was observed on the hydrogel properties and on the drug release profile. The novel blend of drying adjuvants is a smart approach to obtain dried nanocapsules with excellent aqueous redispersion and to maintain the drug release profile of the original suspension in the design of novel skin delivery systems. 相似文献
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Paula S. Haddad Marconi C. Santos Carolina Aparecida de Guzzi Cassago Juliana S. Bernardes Marcelo Bispo de Jesus Amedea B. Seabra 《Journal of nanoparticle research》2016,18(12):369
Recently, increasing interest is spent on the synthesis of superparamagnetic iron oxide nanoparticles, followed by their characterization and evaluation of cytotoxicity towards tumorigenic cell lines. In this work, magnetite (Fe3O4) nanoparticles were synthesized by the polyol method and coated with polyethylene glycol (PEG) and glutathione (GSH), leading to the formation of PEG-Fe3O4 and GSH-PEG-Fe3O4 nanoparticles. The nanoparticles were characterized by state-of-the-art techniques: dynamic light scattering (DLS), atomic force microscopy (AFM), X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, and superconducting quantum interference device (SQUID) magnetic measurements. PEG-Fe3O4 and GSH-PEG-Fe3O4 nanoparticles have crystallite sizes of 10 and 5 nm, respectively, indicating compression in crystalline lattice upon addition of GSH on the nanoparticle surface. Both nanoparticles presented superparamagnetic behavior at room temperature, and AFM images revealed the regular spherical shape of the nanomaterials and the absence of particle aggregation. The average hydrodynamic sizes of PEG-Fe3O4 and GSH-PEG-Fe3O4 nanoparticles were 69 ± 37 and 124 nm ± 75 nm, respectively. The cytotoxicity of both nanoparticles was screened towards human prostatic carcinoma cells (PC-3). The results demonstrated a decrease in PC-3 viability upon treatment with PEG-Fe3O4 or GSH-PEG-Fe3O4 nanoparticles in a concentration-dependent manner. However, the cytotoxicity was not time-dependent. Due to the superparamagnetic behavior of PEG-Fe3O4 or GSH-PEG-Fe3O4 nanoparticles, upon the application of an external magnetic field, those nanoparticles can be guided to the target site yielding local toxic effects to tumor cells with minimal side effects to normal tissues, highlighting the promising uses of iron oxide nanoparticles in biomedical applications. 相似文献
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Francisco M. Pardini Paula A. Faccia Oscar R. Pardini 《International Journal of Polymer Analysis and Characterization》2018,23(3):207-225
This article describes the synthesis and characterization of stimuli-sensitive hybrid films using 2-(diisopropylamino)ethyl methacrylate (DPA), and a polyurethane (PU) base on isophorone diisocyanate. Hybrid films with different amounts of DPA present good film and physicochemical properties. Characterization techniques such as Fourier transform infrared, UV–visible, modulate differential scanning calorimetry, and thermogravimetric analysis reveal chemical interactions between PU and DPA groups. Swelling behavior of films shows a dependence on DPA content, pH, and temperature and different mechanisms of water uptake in response to pH and temperature variations. Hybrid systems would allow controlling water absorption not only through pH or temperature but also from the chosen PU/DPA proportion. 相似文献
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