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pH-probes for Magnetic Resonance Imaging
Šrolerová, Tereza ; Kotek, Jan (advisor) ; Vojtíšek, Pavel (referee)
Macrocyclic ligands are known for their ability to bind paramagnetic lanthanide metal ions to form kinetically inert and thermodynamically stable complexes that can be used as contrast agents for MRI. This thesis deals with the study of new ligands derived from the known parent ligand H8DOTP - 1,4,7,10-tetraazacyclododecane with four pendant methylenephosphonate groups. The prepared new derivatives contain two different pairs of pendant groups, always in opposite positions of the macrocycle. One of the pairs are methylenephosphonate groups, the other pair are methylenephosphinate groups with different substituents on the phosphorus atom. Specifically, it is a compound with a P-H phosphinate group (H6DO2P2PH ), a phenyl group (H6DO2P2PPh ) and a trifluoroethyl group (H6DO2P2Ptfe ). The thesis describes the synthesis of the target ligands, the preparation of their complexes with paramagnetic ions Eu3+ and Yb3+ and their further study using NMR spectroscopy (pH NMR titration and relaxometric NMR measurements). Keywords: H4DOTA, H8DOTP, MRI, contrast agent, lanthanides, macrocyclic ligands, paramagnetic complexes
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Separation of chiral compounds
Šrolerová, Tereza ; Kubíčková, Anna (advisor) ; Křížek, Tomáš (referee)
This bachelor thesis deals with the chiral separation of newly synthesized orthoconic antiferroelectric liquid crystals using ultra-high performance liquid chromatography. These studied compounds differ in the alkyloxy-spacer length, in the presence and/or position of the fluorine atom on the phenyl ring and in the chiral center. The separation took place in a reverse separation mode using a chiral stationary phase based on derivatized amylose. First, the effect of mobile phase flow rate and column temperature on separation efficiency was exanimated. The effect of the composition of the mobile phase on the enantioseparation were studied at the optimum temperature and flow rate. The mobile phase was based on acetonitril, while deionized water was added gradually using isocratic elution. Furthermore, the effect of chromatographic conditions and the structure of the studied analytes on resolution and enantioselectivity was investigated, concretely the presence and position of fluorine atom on pfenyl ring, the length of alkyloxy-spacer and the effect of divergent chiral center. Under optimized chromatography conditions we succeeded to separate all examined substances on the base line. Key words: ultra-high performance chromatography, liquid crystals, enantioseparation, chiral stationary phase, reverse mode
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