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Article Citation - WoS: 10Citation - Scopus: 11Functionalization of Nonwoven Pet Fabrics by Water/O2< Plasma for Biomolecule Mediated Cell Cultivation(Wiley-v C H verlag Gmbh, 2010) Sasmazel, Hilal Turkoglu; Manolache, Sorin; Gumusderelioglu, MenemseThe main target of this study was to obtain COOH functionalities on the surface of 3D, nonwoven polyethylene terephthalate fabrics (NWPFs) by using low pressure water/O-2 plasma assisted treatment. The plasma treatments were performed in a cylindrical, capacitively coupled RF-plasma-reactor and then following steps were performed: in situ (oxalyl chloride vapors) gas/solid reaction to convert -OH functionalities into COCl groups; and hydrolysis under open laboratory conditions using air moisture for final-COOH functionalities. COOH and OH functionalities on the surfaces were detected quantitatively by fluorescent labeling techniques. The COOH-functionalized samples were biologically activated with insulin or heparin molecules by using spacer polyoxyethylene bis-amine (PEO). Successful immobilization was checked qualitatively using electron spectroscopy for chemical analysis (ESCA). The average amount of immobilized insulin and heparin onto NWPF surfaces were determined as 146.09 and 4.81 nmol.cm(-2), respectively. Our results showed that water/O-2 plasma assisted treatment worked very well for functionalization and biofunctionalization of 3D NWPF disks comparing with wet-chemistry methods. Cell culture experiments indicated that functionalization of NWPF disks and/or nanotopographies on the disk surfaces were effective on adhesion and proliferation of L929 mouse fibroblasts.Article Citation - WoS: 17Citation - Scopus: 19Water/O2< Treatment of Pcl Membranes for Biosignal Immobilization(Vsp Bv, 2009) Sasmazel, Hilal Tuerkoglu; Manolache, Sorin; Guemuesderelioglu, MenemseThe main purpose of this study was to obtain COOH functionalities on the surface of poly-epsilon-caprolactone (PCL) membranes using low-pressure water/O-2-plasma-assisted treatment. PCL membranes were prepared using the solvent-casting technique. Then, low-pressure water/O-2 plasma treatments were performed in a cylindrical, capacitively coupled RF-plasma-reactor in three steps: H2O/O-2-plasma treatment; in situ (oxalyl chloride vapors) gas/solid reaction to convert -OH functionalities into -COCl groups; and hydrolysis for final -COOH functionalities. Optimization of plasma modification processes was done using the DoE software program. COOH and OH functionalities on modified surfaces were detected quantitatively using the fluorescent labeling technique and an UVX 300G sensor. Chemical structural information of untreated, plasma treated and oxalyl chloride functionalized PCL membranes were acquired using pyrolysis GC/MS and ESCA analysis. High-resolution AFM images revealed that nanopatterns were more affected than micropatterns by plasma treatments. AFM images recorded with amino-functionalized tips presented increased size of the features on the surface that suggests higher density of the carboxyls on the nanotopographical elements. Low-pressure water/O-2-plasma-treated and oxalyl chloride functionalized samples were biologically activated with insulin and/or heparin biosignal molecules using a PEO (polyoxyethylene bis amine) spacer. The success of the immobilization process was checked qualitatively by ESCA analysis. In addition, fluorescent labeling techniques were used for the quantitative determination of immobilized biomolecules. Cell-culture experiments indicated that biomolecule immobilization onto PCL scaffolds was effective on L929 cell adhesion and proliferation, especially in the presence of heparin. (C) Koninklijke Brill NV, Leiden, 2009
