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Advanced extraction materials for sample preparation in chromatographic analysis
Zatrochová, Slavomíra ; Šatínský, Dalibor (advisor) ; Solich, Petr (referee) ; Ševčík, Juraj (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Training Workplace Department of Analytical Chemistry Doctoral Degree Program Pharmaceutical Analysis Candidate Mgr. Slavomíra Zatrochová Supervisor Prof. RNDr. Dalibor Šatínský, Ph.D. Advisor PharmDr. Ivona Lhotská, Ph.D. Title of Doctoral Thesis Advanced extraction materials for sample preparation in chromatographic analysis The submitted dissertation presents an annotated set of publications focusing on advanced extraction materials in analytical chemistry and their prospective use as sorbents in sample preparation prior to HPLC analysis. The work was created based on the cooperation with the Technical University of Liberec and the University of Valencia in Spain. In the first part, a new sorbent based on a hybrid monolith with a metal-organic framework (MOF) was developed for conventional Teflon-coated magnetic stir bars, and the resulting hybrid monolith was evaluated as a stir bar sorptive extraction (SBSE) sorbent for the extraction of estrogens in water and urine samples. In the second part, the work was focused on nanofibrous and microfibrous polymers and the production of fibers by alternating current (AC) electrospinning. The extraction efficiency, selectivity and stability of different polymer nanofibers were tested. The...
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Advanced extraction materials for sample preparation in chromatographic analysis
Zatrochová, Slavomíra ; Šatínský, Dalibor (advisor) ; Solich, Petr (referee) ; Ševčík, Juraj (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Training Workplace Department of Analytical Chemistry Doctoral Degree Program Pharmaceutical Analysis Candidate Mgr. Slavomíra Zatrochová Supervisor Prof. RNDr. Dalibor Šatínský, Ph.D. Advisor PharmDr. Ivona Lhotská, Ph.D. Title of Doctoral Thesis Advanced extraction materials for sample preparation in chromatographic analysis The submitted dissertation presents an annotated set of publications focusing on advanced extraction materials in analytical chemistry and their prospective use as sorbents in sample preparation prior to HPLC analysis. The work was created based on the cooperation with the Technical University of Liberec and the University of Valencia in Spain. In the first part, a new sorbent based on a hybrid monolith with a metal-organic framework (MOF) was developed for conventional Teflon-coated magnetic stir bars, and the resulting hybrid monolith was evaluated as a stir bar sorptive extraction (SBSE) sorbent for the extraction of estrogens in water and urine samples. In the second part, the work was focused on nanofibrous and microfibrous polymers and the production of fibers by alternating current (AC) electrospinning. The extraction efficiency, selectivity and stability of different polymer nanofibers were tested. The...
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Nano-fibers as a modern extraction sorbents for extraction of samples in chromatographic analysis
Raabová, Hedvika ; Šatínský, Dalibor (advisor) ; Ševčík, Juraj (referee) ; Ventura, Karel (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Training workplace Department of Analytical Chemistry Doctoral degree program Pharmaceutical Analysis Candidate Mgr. Hedvika Raabová Supervisor prof. RNDr. Dalibor Šatínský, Ph.D. Advisor assoc. prof. PharmDr. Lucie Chocholoušová Havlíková, Ph. D. Title of Doctoral Thesis Nanofibers as modern extraction sorbents for sample extraction in chromatographic analysis Extraction techniques represent one of the most common approaches to sample handling. The analytes of interest can be isolated easily even from complex matrices, especially by solid-phase extraction (SPE). Therefore, this technique became very popular and routinely used in laboratories. The variety of commercially available sorbents has made this method even more attractive. Nevertheless, the new sorbent materials are still looked for because of the broadening spectrum of analyzed substances and the increasing demands on selectivity and extraction efficiency. Nanomaterials have been increasingly associated with these properties over the last ten years. Therefore, they are receiving more and more attention related to extraction procedures. The dissertation thesis is focused on the application of nanofibrous polymers as innovative sorbents for solid-phase extraction. First, the...
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Characterization of separation systems for determination of enantiomers
Geryk, Radim ; Tesařová, Eva (advisor) ; Ševčík, Juraj (referee) ; Nováková, Lucie (referee)
(EN) The dissertation thesis is focused on the research and characterization of retention and enantiorecognition mechanisms of chiral stationary phases based on derivatized polysaccharides. The separation systems with a variety of modern stationary phases (both achiral and chiral) were characterized in detail to provide a comprehensive view of the interactions participating in the separation process. The study of the retention/separation behavior significantly facilitates the development and the optimization of new enantioselective methods for a wide variety of compounds. The work deals with the comparison of enantioselective performance of polysaccharide-based chiral stationary phases. The objectives are to show the differences of separation behavior among these chiral stationary phases, as they differ by the nature of the polysaccharide backbone (amylose versus cellulose), by binding of chiral polymer to silica support (coated versus immobilized stationary phase) and by the phenyl moiety in the reversed and normal phase HPLC. In both separation modes amylose-based chiral stationary phases exhibited higher enantioselectivity, especially for acidic and bifunctional analytes. Chiral stationary phases based on derivatized cellulose showed higher enantiodiscrimination potential for basic analytes....
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Chromatograhic characterization of chiral and achiral separation systems
Kučerová, Gabriela ; Tesařová, Eva (advisor) ; Čabala, Radomír (referee) ; Ševčík, Juraj (referee)
Dissertation thesis is a 5-publications' collection concerning characterization and application potential of cyclodextrins, polysaccharides and macrocyclic antibiotics based chiral stationary phases. The effects of stationary phase and mobile phase are studied. This approach ensures the complex insight into separation systems studied. Systems with different nature of chiral selector were studied by HPLC. Namely, macrocyclic antibiotics and derivatized polysaccharides were used for experiments. Former ones provided better results for enantioseparation of non-coded amino acids than latter ones. Dynamic coating procedure was used for preparation of a new chiral stationary phase. Characterization of new cationic cyclodextrin based chiral stationary phase was performed. Linear free energy relationship method was used for characterization of two different separation systems, i.e. newly prepared stationary phase and commercially available stationary phase. Based on results obtained, newly prepared stationary phase showed better results for separation of different achiral groups of analysts. New stationary phase prepared by dynamic coating was compared with chromatographic system, in which the chiral selector was used as a mobile phase additive. The chiral selector used for the two different approaches was...
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Nano-fibers as a modern extraction sorbents for extraction of samples in chromatographic analysis
Raabová, Hedvika ; Šatínský, Dalibor (advisor) ; Ševčík, Juraj (referee) ; Ventura, Karel (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Training workplace Department of Analytical Chemistry Doctoral degree program Pharmaceutical Analysis Candidate Mgr. Hedvika Raabová Supervisor prof. RNDr. Dalibor Šatínský, Ph.D. Advisor assoc. prof. PharmDr. Lucie Chocholoušová Havlíková, Ph. D. Title of Doctoral Thesis Nanofibers as modern extraction sorbents for sample extraction in chromatographic analysis Extraction techniques represent one of the most common approaches to sample handling. The analytes of interest can be isolated easily even from complex matrices, especially by solid-phase extraction (SPE). Therefore, this technique became very popular and routinely used in laboratories. The variety of commercially available sorbents has made this method even more attractive. Nevertheless, the new sorbent materials are still looked for because of the broadening spectrum of analyzed substances and the increasing demands on selectivity and extraction efficiency. Nanomaterials have been increasingly associated with these properties over the last ten years. Therefore, they are receiving more and more attention related to extraction procedures. The dissertation thesis is focused on the application of nanofibrous polymers as innovative sorbents for solid-phase extraction. First, the...
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Advanced Separation Techniques and Data Processing in Capillary Electrophoresis
Ansorge, Martin ; Ušelová, Kateřina (advisor) ; Ševčík, Juraj (referee) ; Masár, Marián (referee)
Techniques of capillary electrophoresis are essential for both the quantitative and qualitative analysis of a large variety of compounds. They find application in many areas of chemistry, from pharmacological industry and food processing, up to highly specialized biotechnological laboratories. Over the last hundred years, their mathematical model has been described with precision. Thus, current research mainly aims for the development of more advanced and more specialized applications. During the greatest boom of affinity capillary electrophoresis within the nineties, many authors would describe similar phenomena under different names. The first part of this work focuses on the consolidation and unification of the problematics and terminology of this method. It also discusses the phenomena which can affect electromigration and separation during electrophoretic processes. We will focus on a specific subset of affinity capillary electrophoresis, partial filling capillary electrophoresis, which, to our knowledge, has not been fully theoretically explored yet, and present a mathematical model allowing the determination of complexation constants and state some limitations of this approach. The second part of this thesis focuses on the development and application of computer softwares, which are meant...
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Nonlinear phenomena in electrokinetic chromatography
Dovhunová, Magda ; Dubský, Pavel (advisor) ; Koval, Dušan (referee) ; Ševčík, Juraj (referee)
Capillary electrophoresis often uses complexing agents since the interaction between the analyte and the complexing agent can result in achieving or improving the separation. Examples of such methods can be electrokinetic chromatography or affinity capillary electrophoresis (ACE). ACE is used to determine the complexing parameters. In case of chiral separation, this issue gets complicated, since the parameters of the two analytes (enantiomers) are not completely independent to one another. Therefore, a procedure has been proposed in this thesis, that should always be used to evaluate the complexing parameters of two enantiomers. Statistical evaluation of these parameters was assessed as well. This work also proposes a method that allows to determine the relative migration order of two enantiomers in two different complexing separation systems. The mathematical description of electrophoresis is based on continuity equations, that are inherently nonlinear. However, these equations can be linearized to obtain an approximate analytical solution. There was recently presented a generalized model, that enables inclusion of complete complexing equilibria in the theoretical description of electromigration. Thus, various phenomena, including nonlinear ones, associated with complexation can be predicted. This...
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Chromatograhic characterization of chiral and achiral separation systems
Kučerová, Gabriela ; Tesařová, Eva (advisor) ; Čabala, Radomír (referee) ; Ševčík, Juraj (referee)
Dissertation thesis is a 5-publications' collection concerning characterization and application potential of cyclodextrins, polysaccharides and macrocyclic antibiotics based chiral stationary phases. The effects of stationary phase and mobile phase are studied. This approach ensures the complex insight into separation systems studied. Systems with different nature of chiral selector were studied by HPLC. Namely, macrocyclic antibiotics and derivatized polysaccharides were used for experiments. Former ones provided better results for enantioseparation of non-coded amino acids than latter ones. Dynamic coating procedure was used for preparation of a new chiral stationary phase. Characterization of new cationic cyclodextrin based chiral stationary phase was performed. Linear free energy relationship method was used for characterization of two different separation systems, i.e. newly prepared stationary phase and commercially available stationary phase. Based on results obtained, newly prepared stationary phase showed better results for separation of different achiral groups of analysts. New stationary phase prepared by dynamic coating was compared with chromatographic system, in which the chiral selector was used as a mobile phase additive. The chiral selector used for the two different approaches was...
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Characterization of electrophoretic separation systems,utilization of system peaks for determination of surfactant properties and optimalization of complex separation systems by the LFER model
Lokajová, Jana ; Tesařová, Eva (advisor) ; Coufal, Pavel (referee) ; Ševčík, Juraj (referee)
Conclusions o We have developď new method for CMC determination that is based on the measurementsof sysrem peaks eigenmobilities in capiiluy "t*o"oo"r*tr. The proposed method is moreprecise and eliminates specific systematic errors .o.*'n* when using some s*ndaťdmethods. The proposed method has U".n opti*i""a "o^ia,sysrcm peaks. ..Ý9 .r4. uE'tl UP.lmzeo considering intensities (amplitudes) of o The implementation of mice description ", ",".o".#'ÍÍ.',11Tffi :: jlTl.Ti#'ff ffiTr,"JT::,l:systems. Simulation prognrms curÍently allow user. to cď"ulate system eigenmobilities andeven to optimize the micellar separation systen. We h;\ *:ffi J:ffi.;: oÍ extended simulation o.o,*,",.u".il.;:T"T1'ffi ' ffill: We have clarified the mobi strength, which "uu,", .pri..ll,l?.jln.fi.r::ř""".J:"# peak due to the BGES ionic additional peak has "oo.a,.o in the electrophe.oror, ,oo**"r' As a consequence an :::::::::'*":u.'*..in.*oo.". identifi cation ", i"*,,.,"'ť"i:TT. *i:ajff:oeen possible using rhe set of different derecrion waveilil:" capirrary zone electrophoresis has been used to revear a structure and charge of nanoparticresin the recentry synthesized bulky porymer micelres ,n-'ltt".*, pH regions and to t3 characterize the effect of the PvP fraction added to PS.PMA on the final structure. ouÍ results have confirmed that...
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