Core/shell type, Ce3+ and Tb3+ doped GdBO3 system: Synthesis and Celecoxib drug delivery application

Çolak, Pelin
Ulusan, Sinem
Banerjee, Sreeparna
Yılmaz, Ayşen
In this study, luminescent and magnetic core/shell Gd1-x-yCexTbyBO3@SiO2 nanoparticles were synthesized and used to design a drug delivery system for Celecoxib (CLX). CLX was chosen as the model drug because it is a nonsteroidal anti-inflammatory drug that is highly hydrophobic with relatively low bioavailability. The core was synthesized by Pechini sol-gel method and silica coating was carried out by a Modified Stöber method. Drug loading was carried out in ethanol with high efficiency and an improved drug dissolution was obtained in phosphate-buffered saline (PBS) at pH 7.4. Dissolution rate of CLX adsorbed onto the drug carrier at different pH conditions were examined and compared.The obtained core particles had a diameter of about 240 nm and core/shell particles had a diameter of about 300 nm. The core/shell particles possessed high luminescence intensity and soft magnetic properties. Drug loading was carried out in ethanol with 12.7% loading efficiency and a substantial decrease of about 8% in photoluminescence intensity was observed in drug loaded samples, which made the quantification of the released drug possible by comparing the photoluminescence intensities. The solubility of the drug was enhanced when compared to crystalline CLX, a sustained release profile was achieved and increasing luminescence intensity was observed during drug release. 55% of the loaded drug was released after 72 h in PBS at pH 7.4 while 20% drug release was observed in a pH 5.5 solution. Drug release at pH 5.5 followed a first order release kinetic model while the release at pH 7.4 followed a Higuchi's kinetic model with Fickian diffusion mechanism. An in vitro loss in cell viability with CLX loaded carrier was observed for the colon cancer cell line HCT-116. These results suggest that the designed drug carrier has promising applications for poorly soluble drugs with improved bioavailability, in addition to its application as a bioimaging agent in fluorescence microscopy and magnetic resonance imaging.
Microporous and Mesoporous Materials


Core/shell type, Ce3+ and Tb3+ doped GdBO3/SiO2 system: synthesis and celecoxib drug delivery applications
Akman, Pelin; Yılmaz, Ayşen,; Department of Chemistry (2019)
Multifunctional nanoparticles have been widely used as drug carriers to control drug release. However, besides controlling drug release, it is important to track the behavior of the drug in body. For this purpose, functionalizing the drug carriers with luminescent or magnetic materials and using them as bioimaging agents have attracted attention in recent years. In this study, luminescent and magnetic core/shell Gd1-xyCexTbyBO3@SiO2 (x=0.05, y=0.05) nanoparticles were synthesized and used in celecoxib drug ...
Structural and electrical characterization of Ag3Ga5Te9 and Ag3In5Se9 crystals
Parlak, Mehmet; Günal, İbrahim; Hasanlı, Nızamı (Wiley, 1998-01-01)
X-ray powder diffraction studies revealed that Ag3Ga5Te9 and Ag3In5Se9 crystallize in orthorhombic and tetragonal systems. respectively. The temperature dependent conductivity and Hall effect measurements have been carried out between 65-480 K. Ag3Ga5Te9 exhibits p-type conduction with a room temperature conductivity of 4.3 x 10(-4) ( and mobility less than 1 cm(2)/V.s. Ag3In5Se9 was identified to be n-type with room temperature conductivity 7.2 x 10(-5) ( and mobility 20 cm(2)/V.s...
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Sevimli, Filiz; Yılmaz, Ayşen (2012-08-01)
The hydrothermally synthesized SBA-15 particles were surface functionalized by post-grafting synthesis method with (3-aminopropyl) triethoxy silane, mercaptopropyl trimethoxy silane and triethoxy methyl silane in order to be used as carrier materials for drug delivery. Amoxicillin was used as a model drug. The adsorption and release properties of calcined and organic-functionalized mesoporous silicas containing terminal primary amine, organothiol and methyl groups toward amoxicillin have been investigated. ...
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Stan, Cristina; Cristescu, C. P.; Severcan, Feride; Dorohoi, Dana (Informa UK Limited, 2006-01-01)
We present a mathematical approach to the experimental data recorded via Fourier transform-infrared spectroscopy regarding the influence of the concentration of the antimicrobial peptide gramicidin S (GS) on the thermotropic phase transition of the dipalmitoylphosphatidyl-glycerol (DPPG) lipid bilayer membrane in DPPG/GS systems. The model is based on the influence of the GS concentration on the parameters of a nonlinear damped oscillator, which models the CH2 symmetric stretching band.
Tailoring the magnetic behavior of polymeric particles for bioapplications
YAKAR, ARZU; Tansik, Gulistan; Keskin, Tugba; Gündüz, Ufuk (2013-05-01)
In this study, magnetic polymeric nanoparticles were prepared use in for targeted drug delivery. First, iron oxide (Fe3O4) magnetic nanoparticles (MNPs) were synthesized by coprecipitation with ferrous and ferric chloride salts. Then, to render the MNPs hydrophobic, the surfaces were covered with oleic acid. Finally, the hydrophobic MNPs (H-MNPs) were encapsulated with polymer. The emulsion evaporation technique was used for the preparation of polymer-coated H-MNP. Poly(DL-lactide-co-glycolide) (PLGA) and c...
Citation Formats
P. Çolak, S. Ulusan, S. Banerjee, and A. Yılmaz, “Core/shell type, Ce3+ and Tb3+ doped GdBO3 system: Synthesis and Celecoxib drug delivery application,” Microporous and Mesoporous Materials, pp. 0–0, 2020, Accessed: 00, 2020. [Online]. Available: