ORGANOSİLİKON KAPİLER MONOLİTLERİN SENTEZİ VE NANO-SIVI KROMATOGRAFİSİ UYGULAMALARINDA SABİT FAZ OLARAK KULLANIMI

Abstract

In this thesis, it is aimed to synthesize new organosilicone hybrid stationary phases and to investigate their morphology and chromotographic performance. For this purpose, the synthesis of POSS-MA monoliths with hydrophobic or hydrophilic properties, depending upon the thiol group carrying ligand was first performed in a one-pot protocol by combining free radical polymerization and thiol-ene chemistry together. Thermal or photo initiator is used for polymerization. Then the capillary monolith was obtained via free radical polymerization. Thiol-ene chemistry was evaluated for the covallent attachment of chromatographic ligands onto the monolithic structure. 1-octadecanthiol, 1-octanethiol, 1-butanethiol and 2-phenylethanethiol were used as the hydrophobic ligand and glutathione and mercaptosuccinic acid were selected as the hydrophilic ligands. Pore-size distribution, specific surface area, crosslinking density, morphology and thiol content of monoliths synthesized under different conditions have been determined by appropriate methods. Reversed phase chromatography applications were carried out by using monoliths with hydrophobic character. In this mode, chromatographic separation of alkylbenzenes, phenos and polycyclic aromatic hydrocarbons were performed. On the other hand, the chromatographic separation of nucleosides, nucleotides and organic acids in hydrophilic interaction chromatography mode was achieved by using monoliths with hydrophilic character. The chromatograms obtained with organosilicone hybrid monoliths and the chromatographic efficiency parameters such as peak solubility, retention factor, plate height calculated from these chromatograms. The results indicated that the proposed organosilicone hybrid stationary phase was obtained with higher mechanical strength, chemical resistance, durability, chromatographic performance and retention factor independent separation efficiency could be obtained comparing to current polymer and silica monoliths.