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Capillary monolithic columns based on copolymer of styrene, divinylbenzene and methacrylic acid and their application for separations of small molecules.
Musilová, Adéla
This work is focused on the preparation and characterization of capillary monolithic columns based on a copolymer of styrene, divinylbenzene and methacrylic acid for the chromatographic separation of small molecules. The capillary monolithic columns were prepared in the quartz capillaries by one-step radical copolymerization reaction of monomers of styrene, divinylbenzene and methacrylic acid in the presence of toluene and isooctane as porogenic solvents and azobisisobutyronitrile as an initiator. The effect of incorporation of methacrylic acid into the polymerization mixture on the separation behavior and efficiency in reversed phase capillary liquid chromatography (CLC) and capillary liquid electrochromatography (CEC) was studied using a test mixture of compounds containing thiourea, phenol, aniline, benzene, toluene, ethylbenzene, propylbenzene and butylbenzene. The Walters test for reversed stationary phases was employed to evaluate the hydrophobicity of the prepared columns. Based on the calculated value of hydrophobicity index of 10.76, the prepared monolithic columns can be classified as very hydrophobic. Excellent repeatability of measurements in CLC mode and very good repeatability of the monolithic column preparation were achieved. The effect of polymerization time on the chromatographic...
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Capillary monolithic columns based on copolymer of styrene, divinylbenzene and methacrylic acid and their application for separations of small molecules.
Musilová, Adéla ; Coufal, Pavel (advisor) ; Čabala, Radomír (referee) ; Sýkora, David (referee)
This work is focused on the preparation and characterization of capillary monolithic columns based on a copolymer of styrene, divinylbenzene and methacrylic acid for the chromatographic separation of small molecules. The capillary monolithic columns were prepared in the quartz capillaries by one-step radical copolymerization reaction of monomers of styrene, divinylbenzene and methacrylic acid in the presence of toluene and isooctane as porogenic solvents and azobisisobutyronitrile as an initiator. The effect of incorporation of methacrylic acid into the polymerization mixture on the separation behavior and efficiency in reversed phase capillary liquid chromatography (CLC) and capillary liquid electrochromatography (CEC) was studied using a test mixture of compounds containing thiourea, phenol, aniline, benzene, toluene, ethylbenzene, propylbenzene and butylbenzene. The Walters test for reversed stationary phases was employed to evaluate the hydrophobicity of the prepared columns. Based on the calculated value of hydrophobicity index of 10.76, the prepared monolithic columns can be classified as very hydrophobic. Excellent repeatability of measurements in CLC mode and very good repeatability of the monolithic column preparation were achieved. The effect of polymerization time on the chromatographic...
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Preparation and testing of capillary monolithic columns for hydrophobic interaction chromatography
Vlková, Michaela ; Sobotníková, Jana (advisor) ; Zima, Jiří (referee)
In frame work of this diploma thesis, monolithic stationary phases based on hydroxymethylmethacrylate were prepared in fused silica capillaries of 320 μm innerdiameter. Monolithic columns were synthesized by a simple procedure using a polymerization mixture, consisting of a monomer N-(hydroxymethyl) methacrylamide (HMMAA), a croslinking agent ethylene dimethacrylate (EDMA), porogenic solvents butane- 1,4-diol, propane-1-ol and an initiator α,α′-azobisisobutyronitrile (AIBN). Prepared HMMA monolithic columns were utilized for separation of mixtures of biologically active compounds, namely peptides with small number of amino acids. Mechanical strength and specific permeability were determined for selected monolithic columns. Keywords: HPLC, HILIC mechanism, hydroxymethyl methacrylate (HMMA) monolithic columns, amino acid, enkephalins.
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Preparation and testing of capillary monolithic columns for hydrophobic interaction chromatography
Vlková, Michaela ; Sobotníková, Jana (advisor) ; Zima, Jiří (referee)
In frame work of this diploma thesis, monolithic stationary phases based on hydroxymethylmethacrylate were prepared in fused silica capillaries of 320 μm innerdiameter. Monolithic columns were synthesized by a simple procedure using a polymerization mixture, consisting of a monomer N-(hydroxymethyl) methacrylamide (HMMAA), a croslinking agent ethylene dimethacrylate (EDMA), porogenic solvents butane- 1,4-diol, propane-1-ol and an initiator α,α′-azobisisobutyronitrile (AIBN). Prepared HMMA monolithic columns were utilized for separation of mixtures of biologically active compounds, namely peptides with small number of amino acids. Mechanical strength and specific permeability were determined for selected monolithic columns. Keywords: HPLC, HILIC mechanism, hydroxymethyl methacrylate (HMMA) monolithic columns, amino acid, enkephalins.
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