Master Degree / Yüksek Lisans Tezleri

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

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Publisher: search.filters.publisher.01. Izmir Institute of TechnologySubject: search.filters.subject.Nanoparticles

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Now showing 1 - 3 of 3
  • Master Thesis
    Synthesis, Characterization and Investigation of Antioxidant, Antibacterial Properties of Different Nanocomplexes Loaded With 6-Thioguanine
    (01. Izmir Institute of Technology, 2024) Şimdim, Zeynep Sena; Mohamed, Gülşah Şanlı
    Metal-Organik çerçeveler (MOF), çekici nitelikleri nedeniyle ve çok dişli organik köprü ligandlarıyla bağlanan metal iyonları veya kümelerden oluşan oldukça gözenekli moleküler yapılardan oluşan yepyeni bir kategori olarak karşımıza çıkmaktadır ve çeşitli ortamlarda kullanılmak üzere önemli miktarda potansiyele sahip olan ZIF-8 ve UiO-66; anti-neoplastik ve immünosüpresif aktiviteye sahip sentetik bir guanozin analogu antimetabolit olan 6-TG'nin terapötik etkinliğini arttırmak ve toksisitesini en aza indirmek için 6-TG bu metal organik çerçevelere yüklenmiştir. Böylelikle ilaç-nanokompleksi elde edilerek nispeten toksik olmayan, biyouyumlu, biyolojik olarak parçalanabilen, katyonik, biyo-yapışkan, düşük immünojenite ve geçirgenliği arttırıcı özelliklerine sahip 6-TG@ZIF-8 ve 6-TG@UiO-66 nanopartikülleri oluşturulmuştur. Buna ek olarak antibiyotiklerin etkisini ve doz-cevap ilişkilerini göstermek ve antibakteriyel direncin oluşturduğu etkileri gözlemlemek için gram negatif bakteri familyasından Escherichia coli (E. coli) ve gram pozitif bakteri familyasından Staphylococcus aureus (S. aureus) üzerinde 6-TG,6-TG@ZIF-8 ve 6-TG@UiO-66 nanoparçacıklarının seri dilüsyon yöntemiyle bakteri inhibisyonuna bakılmıştır. Ayrıca, antioksidan etkiye sahip doğal kaynaklı ve sentetik kaynaklı bileşiklerin keşfi için, in vitro olarak yapılan çeşitli test sistemlerinden biri olan DPPH analizi yapılarak antioksidan aktivite test edilmiştir.
  • Master Thesis
    Effects of Zirconia and Hydroxyapatite Nanoparticles on the Mechanical Properties of the Resin-Based Dental Composites
    (01. Izmir Institute of Technology, 2023) Tunca Taşkıran, Senagül; Tanoğlu, Metin
    The majority of the population suffers from dental caries, one of the most common chronic diseases. Therefore, restoration of teeth is an urgent need. The materials used in restoration are composites prepared by adding inorganic components to the polymeric matrix. However, failure due to fractures and secondary caries is still the main problem. Therefore, studies are continuing to improve the mechanical properties and water sorption and solubility properties of the composite. In this study, effects of zirconia, which improves the mechanical properties, and hydroxyapatite nanoparticles, which are the components of the tooth, on the mechanical properties of the composite were investigated. According to the literature, amounts of additives were determined as 1 and 2 wt.% for zirconia and 3 and 5 wt.% for hydroxyapatite. Nine different composites were prepared by mixing with hand spatulation method and mortar mill. The flexural strength and modulus, compressive strength, depth of cure, water sorption and solubility properties of the composites were investigated. Samples were characterized by using Scanning Electron Microscopy (SEM) and Fourier Transform Infrared Spectroscopy (FTIR). Zirconia and HA particles significantly improved the flexural and compressive strength of the composites. The highest flexural strength was obtained in the sample containing 5 wt.% hydroxyapatite and 1 wt.% zirconia, with an increase of 58% compared to the control sample. The highest compressive strength was obtained in the sample containing 3 wt.% hydroxyapatite and 2 wt.% zirconia, with an increase of 22% compared to the control sample. Therefore, zirconia and HA nanoparticles have a synergistic effect.
  • Master Thesis
    Preparation and Characterization of Serum Albumin Nanoparticles Obtained From Modified Bovine Serum Albumin
    (01. Izmir Institute of Technology, 2021) Özmen Egesoy, Tuğçe; Akdoğan, Yaşar; Demir, Mustafa Muammer
    The serum albumin has been used as a drug nanocarrier for a long time due to its rich drug transportation ability. Here, modified bovine serum albumin (BSA) proteins were obtained by conjugation with ethylenediamine and dopamine molecules, separately. Using these modified proteins, new BSA nanoparticles were obtained by a desolvation method. Native BSA has a net negative charge at the physiological condition. However, ethylenediamine conjugation yields a positive charge on it, and thus produces cationic BSA (cBSA) protein. On the other hand, dopamine functionalization (D-BSA) makes BSA eager to coordinate with transition metals. After preparation of modified proteins (cBSA and D-BSA), their nanoparticles were prepared with desolvation method but using different crosslinking mechanisms. For cBSA NPs preparation, a traditional crosslinking agent of glutaraldehyde was used. However, for D-BSA NPs preparation, Fe(III) ions were added to the system to achieve the stable nanoparticle formation. In order to obtain cBSA NPs, several organic solvents were used as desolvating agents. cBSA NPs with an average size around 200 nm were obtained in a high formation yield (54.8%) only through addition of acetonitrile to the cBSA aqueous solution. Similarly, different desolvating agents were studied to obtain D-BSA NPs. The promising results were obtained upon addition of 1:5 (v/v) of water/acetone mixture. After addition of the desolvating agent, Fe(III) ions were added to the solution to interconnect D-BSA with each other. This connection is pH sensitive therefore albumin nanoparticles were stable at basic pH values but not at acidic pH values. By this way, pH sensitive D-BSA NPs around 300 nm particle sizes were obtained.