Scopus İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12573/395
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Article Citation - WoS: 5Citation - Scopus: 6Modification of Surface Charge Characteristics for Unsupported Nanostructured Titania-Zirconia UF/NF Membrane Top Layers With Calcination Temperature(Springer, 2019-04-18) Erdem, Ilker; Ciftcioglu, MuhsinCeramic membranes are more advantageous alternatives especially for harsh working conditions when compared with the polymeric membranes. The porous multilayer structure of the ceramic membranes (composed of support, intermediate, and top layers) can be prepared via different oxides. Titania and zirconia, having superior properties, are mainly preferred for the top layer formation. The separation properties of the membrane are both dependent on pore morphology and surface charge of the oxide(s) forming the top layer. The effect of surface charge in separation may be very significant in case of filtration of charged species with relatively lower mass as in the ultrafiltration (UF) and nanofiltration (NF). In this study, unsupported membrane top layers were prepared with varying titania/zirconia ratios by sol-gel technique. Their surface charges at different pH conditions after calcination at varying temperatures (400 degrees, 500 degrees, and 600 degrees C) were determined. The surface charge of the pure titania (full Ti) top layer was decreasing with the increasing calcination temperature. The highest magnitudes of zeta potential for both acidic and basic conditions were measured via Zr rich top layer (TiZr2575) at calcination temperatures >= 500 degrees C, which was composed of anatase, rutile (titania), and tetragonal (zirconia) phases after calcination. The tailor-made top layer can be prepared with modifications during membrane preparation.Article Citation - Scopus: 13Paclitaxel-Loaded Polycaprolactone Nanoparticles for Lung Tumors: Formulation, Comprehensive In Vitro Characterization, and Release Kinetic Studies(University of Ankara, 2022-09-29) Ünal, Sedat; Dogan, Osman Talha; Aktaş, YeşimObjective: Today, cancer is still among the most common chronic diseases. Nanoparticular drug delivery systems prepared with biocompatible and biodegradable polymers such as polycaprolactone are rational solution for anticancer agents with poor solubility and low bioavailability. The aim of this study is to prepare paclitaxel-loaded polycaprolactone nanoparticles, which is known to be a potent anticancer, and to elucidate in vitro characteristics and release kinetic mechanisms. Material and Method: It was aimed to prepare paclitaxel-loaded polycaprolactone nanoparticles by nanoprecipitation. Preformulation studies were carried out with different molecular weights of polycaprolactone (Mw: 14.000, Mw: 80.000). Nanoparticles were coated with Chitosan or Poly-l-lysine to obtain cationic surface charge and to increase cellular interaction. Comprehensive characterization of formulations and release kinetic studies were performed. Result and Discussion: The particle size of the formulations ranged from 188 nm to 383 nm. Encapsulation efficiency increased to 77% in different formulations. SEM analysis confirmed the nanoparticles were spherical. Within the scope of in vitro release studies, the release continued for up to 96 hours and less than 50% of the therapeutic load was released in the first 24 hours. Mathematical modeling indicated that the release kinetics fit more than one model with the Korsmeyer-Peppas, Peppas-Sahlin and Weibull models, which show high correlation. © 2023 Elsevier B.V., All rights reserved.