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Synthesis of block copolymers by ring-opening polymerization and post polymerization modification with phenylboronic acid
Dudičová, Dorota ; Uchman, Mariusz Marcin (advisor) ; Strachota, Adam (referee)
This thesis deals with the synthesis of propargyl-functionalized amphiphilic diblock copolymers, poly(ε-caprolactone)-b-poly(ethylene oxide), PgCL-PEO via Ring Opening Polymerization (ROP) using monohydroxyl-terminated PEO block as the macroinitiator and its post polymerization modification via Copper-Catalyzed Azide-Alkyne Click reaction (CuAAC) to introduce phenylboronic acid functionality into block copolymers. A reproducible synthetic protocol was developed for preparation of well-defined functional diblock copolymers. The amphiphilic block copolymers were characterized in terms of molecular weight and dispersity by various techniques: Nuclear Magnetic Resonance (NMR) spectroscopy, Gel Permeation Chromatography (GPC) and Matrix-Assisted Laser Desorption/Ionization Time-of-Flight (MALDI ToF) Mass Spectrometry. Keywords: Amphiphilic block copolymers, CuAAC click, phenylboronic acid, poly-ε- caprolactone, ring-opening polymerization
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Synthesis and characterization of ABA triblock copolymers modified with glucose via thiol - ene click reaction
Hašpl, Adam ; Uchman, Mariusz Marcin (advisor) ; Štěpánek, Miroslav (referee)
The bachelor thesis is focused on method of postpolymerisation modification of two poly(ethylene oxid-b-1,2-butadiene-b-ethylene oxide) amphiphilic block copolymer samples with high content of 1,2-isomer units in inner polybutadiene block by thiolene click. The implemented modification agent was 1-thio-β-D-glucose tetraacetate. The thesis is further focused on methods of copolymer sample characterization before and after modification reaction. Structure and degree of functionalization of vinylic units in polybutadiene block after modification was determined by nuclear magnetic resonance spectroscopy. The dimensions of prepared polymeric particles were studied by static and dynamic light scattering methods. Keywords: ABA triblock copolymers, self-assembly, click reaction, NMR spectroscopy, light scattering
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Development of the new method for in vitro selection of DNA aptamers
Bláhová, Kamila ; Míšek, Jiří (advisor) ; Moserová, Michaela (referee)
Aptamers are short sequences of single-stranded DNA or RNA that are able to specifically bind various molecules (drugs, lipids, sugars, proteins, etc.). These aptamers are isolated from large libraries of random oligonucleotide sequences by SELEX (Systematic Evolution of Ligands by Component Enrichment) or in vitro selection. Despite the success of this method, in vitro selection often requires more than ten rounds of affinity selection as well as optimization of selection conditions. To increase the efficiency of aptamer selection, several methods have been developed that use an increase in the number of secondary structures in random oligonucleotide libraries. These methods, based on increasing the possibility of canonical base pairing in single-stranded oligonucleotides, increased the efficiency of the in vitro selection method. In this work, it was tested whether increasing the probability of occurrence of G-quadruplexes, as structural motifs in random sequences, will lead to increased efficiency of aptamer selection. Four single-stranded DNA libraries with different numbers of guanine (25 %, 35 %, 45 %, 55 %) in a random sequence were used. Streptavidin was chosen as the model molecule for selection, against which several aptamers that are not rich in guanine (G) have previously been selected....
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Synthesis and study of properties of anchors with multiple positive permanent charges and allyl group
Kozel, Ondřej ; Jindřich, Jindřich (advisor) ; Kamlar, Martin (referee)
Solid surface modification is a widely researched topic where there is mostly used covalent bonding. Such modifications are advantageous due to the strength of the newly formed bond but are inconvenient for their financial and material expensiveness. There were also investigated the possibilities of ionic modifications, which are using electrostatic interactions, but which are not widely used-the reason being the weak ionic bond which leads to washing out of the modifier by polar solvents. Nevertheless, new substances were designed which should be more resistant against this issue due to their structure. These substances, containing the propargyl group, were tested in solid surfaces modification. This bachelor work demonstrates the usability of procedures designed for the preparation of such substances with the allylic group. Keywords: permanent positive charges; click reaction; electrostatic binding; ionic modification; quaternary ammonium salts; solid surface modification
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Enzymatic synthesis of DNA modified in the minor groove
Matyašovský, Ján ; Hocek, Michal (advisor) ; Hlaváč, Jan (referee) ; Urban, Milan (referee)
In the first part of the thesis, a series of six modified 2'-deoxyadenosine triphosphates, bearing small functional groups (chloro, amino, methyl, vinyl, ethynyl and phenyl) at position 2 of adenine, was designed and synthesised. They were then tested as substrates for DNA polymerases in enzymatic synthesis of minor-groove modified DNA. The 2-phenyl modified dATP was the only triphosphate unable to be incorporated, meaning that the phenyl group is already too big for minor-groove incorporations. All of the other tested nucleotides were good substrates for tested DNA polymerases [KOD XL, Vent(exo-) and Bst LF] affording minor- groove modified DNA bearing one or four modifications. The vinyl- and ethynyl-modified DNAs were then used for post-synthetic modification of DNA minor groove with fluorescent labels utilising click reactions. Ethynyl group reacted in copper-catalysed alkyne-azide cycloaddition (CuAAC), whereas the vinyl group participated in thiol-ene reaction. This procedure allowed for the attachment of big functional groups otherwise unable to be installed into the DNA minor groove using direct enzymatic incorporation. The second part of the thesis was devoted to the study of 2-alkylamino-2'- deoxyadenosine triphosphates and their use in enzymatic synthesis of base-modified ONs and DNA....
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Synthesis of block copolymers by ring-opening polymerization and post polymerization modification with phenylboronic acid
Dudičová, Dorota ; Uchman, Mariusz Marcin (advisor) ; Strachota, Adam (referee)
This thesis deals with the synthesis of propargyl-functionalized amphiphilic diblock copolymers, poly(ε-caprolactone)-b-poly(ethylene oxide), PgCL-PEO via Ring Opening Polymerization (ROP) using monohydroxyl-terminated PEO block as the macroinitiator and its post polymerization modification via Copper-Catalyzed Azide-Alkyne Click reaction (CuAAC) to introduce phenylboronic acid functionality into block copolymers. A reproducible synthetic protocol was developed for preparation of well-defined functional diblock copolymers. The amphiphilic block copolymers were characterized in terms of molecular weight and dispersity by various techniques: Nuclear Magnetic Resonance (NMR) spectroscopy, Gel Permeation Chromatography (GPC) and Matrix-Assisted Laser Desorption/Ionization Time-of-Flight (MALDI ToF) Mass Spectrometry. Keywords: Amphiphilic block copolymers, CuAAC click, phenylboronic acid, poly-ε- caprolactone, ring-opening polymerization
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