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Boron cluster conjugates as building blocks for the preparation of polymeric nanostructures
Steiner, Filip ; Matějíček, Pavel (advisor) ; Ďorďovič, Vladimír (referee)
Charles University in Prague Faculty of Science Department of Physical and Macromolecular Chemistry Author: Bc. Filip Steiner Supervisor: prof. RNDr. Pavel Matějíček, Ph.D. Advisor: Ing. Mariusz Uchman, Ph.D. Title: Boron Cluster Conjugates as Building Blocks for the Preparation of Polymeric Nanostructures Abstract This diploma thesis investigates the synthesis and supramolecular behaviour of amphiphilic conjugates of closo-dodecaborate dianion, [B12H12]2- , with polycationic diblock copolymer poly(ethylene oxide)-block-poly(2-(N, N, N', N'-tetramethyl guanidium ethyl acrylate), PEOn-b-PGEAm. The boron cluster dumbbells were synthesised by the exoskeletal, electrophile-induced nucleophilic substitution (EINS) and by subsequently ring-opening reaction with various aliphatic diols, resulting in a hybrid dumbbell molecule. These molecules were used for preparation of nanoparticles by co- assembly with polycationic diblock copolymer in water. Resulted nanostructures were characterised by static and dynamic light scattering and NMR spectroscopy. Keywords: boron cluster compounds, polymeric nanoparticles, co-assembly, NMR, light scattering
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Self-assembly of boron cluster compounds and their coassembly with polymers
Ďorďovič, Vladimír ; Matějíček, Pavel (advisor) ; Adamczyk-Wozniak, Agnieszka (referee) ; Nunez Aguilera, Maria Rosario (referee)
This thesis focuses on the self-assembly of the boron cluster compounds and the coassembly of metallacaborane cobalt bis(dicarbollide), COSAN, with hydrophilic polymers. The research was motivated by the discovery of HIV inhibition by COSAN and its conjugates. Therefore, we decided to study in detail the behavior of boron cluster compounds in water. We demonstrated the amphiphilic character of several boranes and carboranes by the study of surface tension and self-assembly despite the absence of classical amphiphilic topology. The behavior of COSAN showed similarities with classical surfactants, such as SDS, whereas the behavior of smaller clusters with high charge density reminded of hydrotropes or chaotropes. Furthermore, we searched for the most suitable carriers of COSAN for drug delivery. Based on the earlier findings that COSAN interacts with both poly(ethylene oxide), PEO, and poly(2-oxazoline), POX, we prepared nanoparticles by mixing COSAN with block copolymers of various types of POX. Comparing linear and star-like block copolymers, we showed that the polymer architecture has a crucial role in the morphology of nanoparticles. In addition, we proved different selectivity of alkaline cations towards PEO and POX, resulting in the different structures of nanoparticles depending on the present...
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Interaction of metallacarboranes with biocompatible polymers in solutions
Ďorďovič, Vladimír ; Matějíček, Pavel (advisor) ; Cígler, Petr (referee)
The bachelor thesis deals with the behavior of aqueous solutions of polystyrene- block-poly(ethylene oxide), PS-PEO, and poly(ethylene oxide)-block-poly(2-ethyl oxazoline), PEO-PEOX, and their interaction with sodium 3-cobalt bis(1,2-dicarbollide), NaCoD. The prepared nanoparticles were characterized by static and dynamic light scattering, AFM and cryo-TEM. While PEO-PEOX is molecularly soluble in water, PS- PEO forms micelles with PS core and PEO shell. We determined by dialysis that CoD¯ interacts with both PEO and PEOX segments depending on the salt concentration. Even small amount of NaCoD results in destabilization of PS-PEO micelles. On the other hand, PEO-PEOX mixtures with NaCoD in salted aqueous solutions contain vesicles with radii 69 nm.
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ASSOCIATION BEHAVIOUR OF CARBORANES AND THEIR INTERACTIONS WITH POLYMERS IN SOLUTIONS
Ďorďovič, Vladimír
This diploma thesis deals with the behavior of cobalt bis(dicarbollide) and its derivatives containing polyethylene oxide linkers in aqueous and salted solution and their interactions with some biocompatible block copolymers. In this study we chose diblock copolymer poly(ethylene oxide)-block-poly(2-ethyl oxazoline), PEO-PEOX, triblock copolymer poly(2- ethyl oxazoline)-block-poly(ethylene oxide)-block-poly(2-ethyl oxazoline), PEOX-PEO- PEOX and starlike polymer 4-arm poly(ethylene oxide)-block-poly(2-methyl oxazoline), 4- arm PEO-PMOX. Solubility and change of hydrodynamic radius of metallacarborane particles depending on the cation of corresponding salt solution was studied. Solubility and size of particles changes depending on counterion of metallacarborane and also on the length and type of PEG linker of carborane compound. In solutions with polymer cobalt bis(dicarbollide) and his conjugates form particles composed of complex polymer/caborane. Adding polymer increase solubility of carborane and in most cases it decreases the size of particles in solution. These systems were studied by means of light scattering, UV-VIS spectroscopy, ITC, NMR and SAXS.
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Self-assembly of boron cluster compounds and their coassembly with polymers
Ďorďovič, Vladimír ; Matějíček, Pavel (advisor) ; Adamczyk-Wozniak, Agnieszka (referee) ; Nunez Aguilera, Maria Rosario (referee)
This thesis focuses on the self-assembly of the boron cluster compounds and the coassembly of metallacaborane cobalt bis(dicarbollide), COSAN, with hydrophilic polymers. The research was motivated by the discovery of HIV inhibition by COSAN and its conjugates. Therefore, we decided to study in detail the behavior of boron cluster compounds in water. We demonstrated the amphiphilic character of several boranes and carboranes by the study of surface tension and self-assembly despite the absence of classical amphiphilic topology. The behavior of COSAN showed similarities with classical surfactants, such as SDS, whereas the behavior of smaller clusters with high charge density reminded of hydrotropes or chaotropes. Furthermore, we searched for the most suitable carriers of COSAN for drug delivery. Based on the earlier findings that COSAN interacts with both poly(ethylene oxide), PEO, and poly(2-oxazoline), POX, we prepared nanoparticles by mixing COSAN with block copolymers of various types of POX. Comparing linear and star-like block copolymers, we showed that the polymer architecture has a crucial role in the morphology of nanoparticles. In addition, we proved different selectivity of alkaline cations towards PEO and POX, resulting in the different structures of nanoparticles depending on the present...
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ASSOCIATION BEHAVIOUR OF CARBORANES AND THEIR INTERACTIONS WITH POLYMERS IN SOLUTIONS
Ďorďovič, Vladimír ; Matějíček, Pavel (advisor) ; Cígler, Petr (referee)
This diploma thesis deals with the behavior of cobalt bis(dicarbollide) and its derivatives containing polyethylene oxide linkers in aqueous and salted solution and their interactions with some biocompatible block copolymers. In this study we chose diblock copolymer poly(ethylene oxide)-block-poly(2-ethyl oxazoline), PEO-PEOX, triblock copolymer poly(2- ethyl oxazoline)-block-poly(ethylene oxide)-block-poly(2-ethyl oxazoline), PEOX-PEO- PEOX and starlike polymer 4-arm poly(ethylene oxide)-block-poly(2-methyl oxazoline), 4- arm PEO-PMOX. Solubility and change of hydrodynamic radius of metallacarborane particles depending on the cation of corresponding salt solution was studied. Solubility and size of particles changes depending on counterion of metallacarborane and also on the length and type of PEG linker of carborane compound. In solutions with polymer cobalt bis(dicarbollide) and his conjugates form particles composed of complex polymer/caborane. Adding polymer increase solubility of carborane and in most cases it decreases the size of particles in solution. These systems were studied by means of light scattering, UV-VIS spectroscopy, ITC, NMR and SAXS.
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ASSOCIATION BEHAVIOUR OF CARBORANES AND THEIR INTERACTIONS WITH POLYMERS IN SOLUTIONS
Ďorďovič, Vladimír
This diploma thesis deals with the behavior of cobalt bis(dicarbollide) and its derivatives containing polyethylene oxide linkers in aqueous and salted solution and their interactions with some biocompatible block copolymers. In this study we chose diblock copolymer poly(ethylene oxide)-block-poly(2-ethyl oxazoline), PEO-PEOX, triblock copolymer poly(2- ethyl oxazoline)-block-poly(ethylene oxide)-block-poly(2-ethyl oxazoline), PEOX-PEO- PEOX and starlike polymer 4-arm poly(ethylene oxide)-block-poly(2-methyl oxazoline), 4- arm PEO-PMOX. Solubility and change of hydrodynamic radius of metallacarborane particles depending on the cation of corresponding salt solution was studied. Solubility and size of particles changes depending on counterion of metallacarborane and also on the length and type of PEG linker of carborane compound. In solutions with polymer cobalt bis(dicarbollide) and his conjugates form particles composed of complex polymer/caborane. Adding polymer increase solubility of carborane and in most cases it decreases the size of particles in solution. These systems were studied by means of light scattering, UV-VIS spectroscopy, ITC, NMR and SAXS.
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Interaction of metallacarboranes with biocompatible polymers in solutions
Ďorďovič, Vladimír ; Matějíček, Pavel (advisor) ; Cígler, Petr (referee)
The bachelor thesis deals with the behavior of aqueous solutions of polystyrene- block-poly(ethylene oxide), PS-PEO, and poly(ethylene oxide)-block-poly(2-ethyl oxazoline), PEO-PEOX, and their interaction with sodium 3-cobalt bis(1,2-dicarbollide), NaCoD. The prepared nanoparticles were characterized by static and dynamic light scattering, AFM and cryo-TEM. While PEO-PEOX is molecularly soluble in water, PS- PEO forms micelles with PS core and PEO shell. We determined by dialysis that CoD¯ interacts with both PEO and PEOX segments depending on the salt concentration. Even small amount of NaCoD results in destabilization of PS-PEO micelles. On the other hand, PEO-PEOX mixtures with NaCoD in salted aqueous solutions contain vesicles with radii 69 nm.
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