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Article Citation - WoS: 1Citation - Scopus: 1PMMA-Based Electrospun Composite Fibers for Dye Adsorption From Water(Sage Publications Ltd, 2025) Cakar, Ilknur; Yesil, Sertan; Bayram, GoknurPoly (methyl methacrylate) (PMMA) and PMMA/poly (ethylene glycol) (PEG)-based composite fibers were produced using electrospinning technique with two different additives; halloysite nanotubes (HNTs) and boron phosphate (BPO4). The effect of the additives on the morphology, wettability and dye adsorption properties of electrospun fibers were investigated by Scanning Electron Microscopy (SEM), water contact angle measurement and UV-VIS spectrophotometry. The results of SEM analysis indicated that addition of PEG resulted in thinner average fiber diameter and beaded structure. Additionally, it was also observed that incorporating both HNT and BPO4 to the PMMA solution caused increased fiber diameter which might be due to increased solution viscosity. For PMMA fibers containing 3 wt% HNT, the highest average diameter and water contact angle were measured as 2204 +/- 302 nm and 110.29 +/- 3.9 degrees, respectively. The produced fibers were tested for the capability to adsorb methylene blue (MB) and methyl orange (MO) from aqueous solutions. Dye adsorption capacity of the samples increased by addition of HNT and BPO4. According to adsorption capacity results, PMMA/PEG/BPO4 composite sample containing 5 wt% BPO4, with an adsorption capacity of 0.76 mg/g, was determined as adsorbent for kinetic and isotherm studies. The adsorption kinetics were well described by the pseudo-second-order model, and equilibrium data were correlated with the Langmuir model.Article Citation - WoS: 45Citation - Scopus: 46Novel Hybrid Scaffolds for the Cultivation of Osteoblast Cells(Elsevier, 2011) Sasmazel, Hilal TurkogluIn this study, natural biodegradable polysaccharide, chitosan, and synthetic biodegradable polymer, poly(epsilon-caprolactone) (PCL) were used to prepare 3D, hybrid polymeric tissue scaffolds (PCL/chitosan blend and PCL/chitosan/PCL layer by layer scaffolds) by using the electrospinning technique. The hybrid scaffolds were developed through HA addition to accelerate osteoblast cell growth. Characteristic examinations of the scaffolds were performed by micrometer, SEM, contact angle measurement system, ATR-FTIR, tensile machine and swelling experiments. The thickness of all electrospun scaffolds was determined in the range of 0.010 +/- 0.001-0.012 +/- 0.002 mm. In order to optimize electrospinning processes, suitable bead-free and uniform scaffolds were selected by using SEM images. Blending of PCL with chitosan resulted in better hydrophilicity for the PCL/chitosan scaffolds. The characteristic peaks of PCL and chitosan in the blend and layer by layer nanofibers were observed. The PCL/chitosan/PCL layer by layer structure had higher elastic modulus and tensile strength values than both individual PCL and chitosan structures. The layer by layer scaffolds exhibited the PBS absorption values of 184.2; 197.2% which were higher than those of PCL scaffolds but lower than those of PCL/chitosan blend scaffolds. SaOs-2 osteosarcoma cell culture studies showed that the highest ALP activities belonged to novel PCL/chitosan/PCL layer by layer scaffolds meaning better cell differentiation on the surfaces. (C) 2011 Elsevier B.V. All rights reserved.Article Citation - Scopus: 1Surface Patterning of Poly(ε-Caprolactone) Scaffolds by Electrospinning for Monitoring Cell Biomass Behavior(Springer, 2022) Albayrak, Deniz; Sasmazel, Hilal TurkogluThe aim of this work was to produce three-dimensional fibrous surface patterns of poly(epsilon-caprolactone) (PCL), onto two-dimensional smooth solvent cast PCL surfaces with an electrospinning method by using a mask/stencil for monitoring cell biomass behavior. The characterizations of produced scaffolds were done by thickness measurements, scanning electron microscopy (SEM) analyses, contact angle (CA) measurements, Fourier-transform infrared spectroscopy (FTIR), and mechanical tests. According to SEM micrographs, all of the electrospun scaffold surfaces exhibited bead-free and uniform morphology while solvent cast surfaces were smooth and nonporous. CA measurements revealed that the solvent cast surfaces had moderate hydrophilicity (similar to 60 degrees) while electrospun regions had a more hydrophobic character (similar to 110 degrees for fully electrospun surfaces and similar to 85 degrees for electrospun patterns). Mechanical testing showed the produced scaffolds had a brittle character. Moreover, cell culture studies were performed with mouse fibroblast (L929) cells for 7 days period, and cell attachment assay, MTT assay, fluorescence, and SEM analyses were done. Cell culture studies indicated that the solvent cast and electrospun patterns have different characteristics for cell behavior. Thus, cell movement, attachment, and proliferation can be directed and monitored by obtaining different surface topographies in a single substrate surface. Based on the results of this study, it was found that patterns consisting of polymeric nanofiber structures can also be created directly by the electrospinning method.Article Citation - WoS: 64Citation - Scopus: 70Nanosized Cap-Silk Fibroin-pcl-peg-pcl/Pcl Based Bilayer Membranes for Guided Bone Regeneration(Elsevier Science Bv, 2017) Turkkan, Sibel; Pazarceviren, A. Engin; Keskin, Dilek; Machin, Nesrin E.; Duygulu, Ozgur; Tezcaner, AysenGuided bone regeneration (GBR) concept has been developed to prevent the formation of non-functional scar tissue layer on defect site by undertaking barrier role. In this study, a new bilayer membrane which consisted of one layer of electrospun silk fibroin/PCL-PEG-PCL incorporating nanocalcium phosphate (SPCA)(1) and one layer of PCL membrane was developed for GBR. To improve the osteoconductivity of membranes, nanosized calcium phosphate particles synthesized by Flame Spray Pyrolysis method were incorporated into membranes at 10% (wt) (SPCA10) and 20% (wt) (SPCA20) of the polymer content. The structural and chemical analyses revealed the well-integrated two layers of membranes with a total thickness of ca 100 mu m. In the regenerative layer, the highly porous mesh structure had a thickness of 12.6 mu m with randomly oriented fibers having diameters around 760 nm, and nanoparticles dispersed homogenously. The mechanical test results showed remarkable improvement on the tensile strength of membranes with incorporation of nanoparticles. Higher water affinity of nanoCaP included membranes was proved by lower contact angle values and higher percent water uptake capacity. Biomineralization assay revealed that nucleation and growth of apatites around fibers of SPCA10 and SPCA20 were apparent while on SPCAO apatite minerals were barely detected after 10 days. Human dental pulp stem cells (DPSC) were seeded on electrospun layer of the bilayer membranes for biocompatibility and osteo-compatibility study. Increasing narioCaP amount resulted in higher cell adhesion, proliferation, ALP activity and calcium deposition on membranes. These overall results confirmed the biocompatibility and potential applicability of proposed membranes for GBR treatments. (C) 2017 Elsevier B.V. All rights reserved.
