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Article Citation - WoS: 39Citation - Scopus: 44A Novel Treatment Strategy for Preterm Birth: Intra-Vaginal Progesterone-Loaded Fibrous Patches(Elsevier, 2020) Cam, Muhammet Emin; Hazar-Yavuz, Ayse Nur; Cesur, Sumeyye; Ozkan, Ozan; Alenezi, Hussain; Sasmazel, Hilal Turkoglu; Edirisinghe, MohanProgesterone-loaded poly(lactic) acid fibrous polymeric patches were produced using electrospinning and pressurized gyration for infra-vaginal application to prevent preterm birth. The patches were intravaginally inserted into rats in the final week of their pregnancy, equivalent to the third trimester of human pregnancy. Maintenance tocolysis with progesterone-loaded patches was elucidated by recording the contractile response of uterine smooth muscle to noradrenaline in pregnant rats. Both progesterone-loaded patches indicated similar results from release and thermal studies, however, patches obtained by electrospinning had smaller average diameters and more uniform dispersion compared to pressurized gyration. Patches obtained by pressurized gyration had better results in production yield and tensile strength than electrospinning; thereby pressurized gyration is better suited for scaled-up production. The patches did not affect cell attachment, viability, and proliferation on Vero cells negatively. Consequently, progesterone-loaded patches are a novel and successful treatment strategy for preventing preterm birth.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 Development of Electrospun We43 Magnesium Alloy-Like Compound(Amer Scientific Publishers, 2020) Ozkan, Ozan; Sasmazel, Hilal Turkoglu; Biskin, ErhanMetallic structures are conventionally fabricated with high temperature/deformation processes resulting the smallest possible microscopic structures in the order of several hundreds of micrometer. Therefore, to obtain structures with fibers smaller than 100 Am, those are unsuitable. In this study, electrospinning, a fiber fabrication technique commonly used for polymers, was adopted to fabricate a WE43 magnesium alloy-like fibrous structure. The aim is to adopt metallic WE43 alloy to regenerative medicine using tissue engineering approach by mimicking its composition inside of a fibrous structure. The solution required for electrospinning was obtained with water soluble nitrates of elements in WE43 alloy, and PVP or PVA were added to obtain a spinnable viscosity which was pyrolised away during heat treatment. Electrospinning parameters were optimized with naked-eye observations and SEM as 1.5 g salts and 5 wt.% PVA containing solution prepared at 90 degrees C and electrospun under 30 kV from a distance of 12-15 cm with a feeding rate of 5 mu l/min. Then the samples were subjected to a multi-step heat treatment under argon to remove the polymer and calcinate the nitrates into oxides which was designed based on thermal analyses and reaction kinetics calculations as 6 h at 230 degrees C, 8.5 h at 390 degrees C, 5 h at 465 degrees C, 80 h at 500 degrees C and 10 h at 505 degrees C, consecutively. The characterizations conducted in terms of structure, composition and crystallinity with XRD, XPS, EDX and SEM showed that it is possible to obtain MgaYbNdcZrdOx), (empirical) fibers with the same composition as WE43 in sub-millimeter sizes using this approach.Article Citation - WoS: 21Development of Poly(vinyl Alcohol) (pva)/Reduced Graphene Oxide (rgo) Electrospun Mats(Amer Scientific Publishers, 2019) Gozutok, Melike; Sadhu, Veera; Sasmazel, Hilal TurkogluIn this study, electrospun reduced graphene oxide (rGO) and poly(vinyl alcohol) (PVA) nanocomposites were developed with the concentration of rGO as 0.5 and 1.0 wt% by dispersing rGO in the PVA solution without using any co-solvent which may cause toxic effect for possible applications like packaging and tissue engineering. Water solubility of PVA was eliminated by UV-radiation crosslinking method. SEM analysis proved that continuous and bead-free nanofibers were obtained by electrospinning process and all electrospun mats had similar fiber characteristics with homogeneous fiber morphology. The average fiber diameter (nm), inter-fiber pore size (mu m) and the porosity (%) were increased with rGO incorporation. Additionally, enhanced tensile properties was achieved by rGO addition as the highest tensile strength was obtained as similar to 5 MPa for electrospun PVA+ 1.0 wt% rGO nanocomposites. ATR-FTIR analyses showed that there was a relatively strong interfacial interaction between rGO and PVA. Moreover, the thermal stability of obtained nanocomposites was enhanced by rGO addition without changing the crystal structure of PVA proved by XRD analyses. Also, improved electrical conductivity of the nanocomposites was obtained by rGO content as the highest conductivity (similar to 11 mu S.cm(-1)) was measured for electrospun PVA+ 1.0 wt% rGO.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.
