Master Degree / Yüksek Lisans Tezleri

Permanent URI for this collectionhttps://hdl.handle.net/11147/3008

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2009 - 200912010 - 20133

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Author: search.filters.author.Özçelik, SerdarSubject: search.filters.subject.Nanoparticles

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Now showing 1 - 4 of 4
  • Master Thesis
    Development of a Novel Electrocardiography Sensor Based on a Composite Silver Chloride Nanoparticles and Polyaniline
    (Izmir Institute of Technology, 2013) Taşcıoğlu, Didem; Özçelik, Serdar
    The electrical activity of the heart is detected by electrodes attached to the surface of the skin. These electrodes detect bioelectrical signals in the human body. Physilogical status of heart condition especially cardiovascular diseases and disturbances in the cardiac rthym are recorded by electrocardiography (ECG). Despite the fact that the usage of disposable ECG electrodes in our country is substantial nearly as 70 million in 2010, these electrodes are not fabricated in Turkey. In the scope of this study, it was aimed to develop a novel sensor based on synthesized AgCl/Polyaniline nanocomposites for ECG electrodes. In this study, the production of silver chloride (AgCl) nanoparticles was achieved by the polyol method. ABS (Acrylonitrile butadiene styrene) was used as a supporting material of the ECG electrode. Synthesized AgCl nanoparticles were not easily adsorbed on the surface of ABS. We develop a synthetic chemistry to perform simultaneous synthesis of AgCl nanoparticle and polymerization of aniline on surface of ABS. Polyaniline acts as a chemical linker between the nanoparticle and ABS surface in the same batch reactor. The synthesized composite based on polyaniline and AgCl nanoparticles completely covers the surface of ABS. To evaluate electrodes, we fabricated a disposable ECG electrode and compared it with the disposable electrodes that are commercially available. The electrocardiography data indicated that the fabricated electrodes were demonstrated a performance which is comparable with the commercial electrodes. The results demonstrate that a novel ECG electrodes can be manufactured based on this new composite material and method develop in our laboratory.
  • Master Thesis
    Synthesis and Characterization of Monodispere Silica Based Functional Nanoparticles for Multi-Purpose Applications
    (Izmir Institute of Technology, 2009) Altın, Burcu; Özçelik, Serdar
    The Stöber method was performed to tune the size of monodisperse silica nanoparticles in the range of 10 to 500 nm. It was observed that increasing amount of reactants favors the formation of larger particles A Stöber method in the presence of L-lysine as a catalyst instead of ammonia was developed to prepare well-ordered, highly monodisperse silica nanoparticles based on the hydrolysis and condensation of TEOS. The effect of medium temperature, amounts of L-lysine, TEOS, octane and dye on the size of particle was investigated. It was found that L-arginine increased the size of particles. The amount of TEOS was determined to be 50.0 mmol to obtain the smallest size of particle. The mole of L-lysine slightly altered the size of particles, however the surface of particles was substantially covered by L-lysine. The presence of octane does not change the size of particles. The amount of dye molecule Rhodamine B isothiocyanate (RBITC) does not alter the size of nanoparticles. We showed that temperature plays important role tuning the particle size from 5.0 nm to 80.0 nm.MTT assay indicates no cytotoxicity of the silica particles against MCF-7 (human breast cancer cell lines) and PC-3 (human prostate cancer cell lines) cancer cell lines. The particles enter to the cells within 5 minutes with a concentration of 0.1.g/mL. We propose that these particles can be used in the field of bioimaging and drug delivery.
  • Master Thesis
    Preparation of Electrospun Composite Fibers Based on Ps-pi-ps/Cdsxse1-x Nanoparticles
    (Izmir Institute of Technology, 2011) Aşkın, Görkem; Demir, Mustafa Muammer; Özçelik, Serdar
    Polymeric fibrous films were prepared based on polystyrene-b-polyisoprene-bpolystyrene triblock copolymer (SIS) and CdSxSe1-x nanoparticles by electrospinning process. SIS with 14 wt % Styrene (14% PS-SIS) and 22 wt % Styrene (22% PS-SIS) triblock copolymers were employed. Both of them undergo microphase separation. While the former shows cylinder-like morphology, the latter exhibits the lamellae one. CdSxSe1-x partciles were stabilized by two different surfactant molecules: i) n-trioctylphosphine oxide (TOPO) and ii) oleic acid (OA). When the particles were blended with 22% PS-SIS, particles capped with TOPO preferentially filled to PS domain whereas particles capped with OA loaded into the PI domain. Composite electrospun fibers were prepared with a diameter of 1.5 mm on average. Electrospinning parameters (potential difference, solution concentration, flow rate) were investigated on fiber morphology. The films are colorless under day light and have strong green emission under UV light.
  • Master Thesis
    Snythesis, Characterization of Borosilicate Nanoparticles and Investigation of Their Cytotoxicity and Genotoxicity in Human Cell Lines
    (Izmir Institute of Technology, 2011) Öztürk İlgü, Ekin; Özçelik, Serdar
    In this study, firstly, we aimed to synthesize silica and borosilicate nanoparticles by the Stöber method. We then investigated the biological response of bronchoalveolar carcinoma-derived cells (A549) and healthy bronchoalveolar cells (BEAS2B) against the silica and borosilicate nanoparticles, by evaluating cytotoxicity and genotoxicity. The nanoparticles were synthesized by a modified Stöber method. To prepare borosilicate nanoparticles tri methoxy boroxine (TMB) was used as boron source to coat the surface of the silica nanoparticles. By varying the amounts of ethanol and ammonia the size of nanoparticles were tuned from 60 to 450 nm. We proved the presence of boron in the borosilicate nanoparticles by Energy-Dispersive X-ray (EDX), Fourier Transformed Infrared (FTIR) spectroscopy and an acid-base titration method. Cytotoxicity and genotoxicity induced both silica and borosilicate nanoparticles were investigated for the cell lines of A549 and BEAS-2B. Silica and borosilicate nanoparticles in all three sizes and dosages up to 500 μg/mL did not induce cytotoxic effects in A549 cells with incubation time up to 72 hours. The same amount of particles did not result in any cytotoxicity in BEAS-2B cells for 24 hours incubation, but they showed cytotoxic effects when the incubation time was increased to 48 and 72 hours. Furthermore, nanoparticles with sizes of 60 and 100 nm showed no genotoxicity for A549 but for BEAS-2B cells, silica nanoparticles induced genotoxic effects contrary to borosilicate nanoparticles.