Tezin Türü: Yüksek Lisans
Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Fen Edebiyat Fakültesi, Kimya Bölümü, Türkiye
Tezin Onay Tarihi: 2016
Öğrenci: GİZEM TEKİN
Eş Danışman: AKIN AKDAĞ, ALİ GÖKMEN
Özet:DNA achieved its double helix form with the help of hydrophilic and hydrophobic interactions. When the sequence of the DNA is examined, it is seen that the DNA bases are the most hydrophobic part, and therefore; they are located at the innermost part of the double helix to avoid interaction with water. This location also enables them to form hydrogen bonds with the complementary DNA base rather than forming them with water. The next part in the sequence is the sugars which have higher solubility in water compared to the DNA bases and lower solubility compared to the upcoming part, phosphate groups. The most hydrophilic part is the phosphate group which is located at the outermost part of the helix to increase its contact with water. Thus this is the thermodynamically most favorable form in water. With this in mind, DNA structure was taken as a model to examine molecular structures’ formation and behavior in water. Meanwhile, a new concept, differential solvation, was introduced and developed. It was vi suggested that with the help of differential solvation, molecular assemblies would be formed in water. Whether differential solvation is responsible for the formation of such molecular structures or not is the main question in this thesis. To address this, compounds having differential solvation in water were designed and synthesized. The final products’ behaviors in water and in organic solvents were studied with NMR, UVVis, fluorescence, DLS and CD spectroscopy. Mainly, a compound which has differential solvation in water and a compound which has not differential solvation in water were compared and contrasted with the help of above mentioned methods. In literature, molecular assemblies are widely characterized and investigated by circular dichroism (CD) spectroscopy. Since this instrument is very expensive and hard to reach, a homemade CD spectrometer was also built during this study. Necessary optical components were purchased and aligned to create circularly polarized light. The performance of the instrument was also compared with a commercial one. Although both the conceptual and the instrumentation part need further studies, available data obtained during this thesis proves the formation molecular assemblies by differential solvation in water.