|
|
Preconcentration of ion compounds from sample by epitachophoresis
Kocianová, Vanda ; Dvořák, Miloš (referee) ; Voráčová,, Ivona (advisor)
Epitachophoresis is newly developed method, which allows to separate and concentrate analytes from large volumes of complex samples. Principle is based on isotachophoresis and utilize discontinuous electrolyte system. Different design of device is used, its round shaped and due to that acceleration of analytes zone migration occurs during separation towards centre of device and at the same time widening of zones happens. Focusation, concentration and separation of analytes between leading and terminating electrolyte progress from outer line of device towards its centre. It is necessary to stabilize this boundary to prevent mixing of leading and terminating electrolyte. Main target of this diploma thesis is optimization of epitachophoretic conditions, mainly electrolyte boundary stabilization options. Tested stabilizing media were agarose gels, foamed polymer disks and PDMS columns. All leading and terminating electrolyte boundary stabilizing media undergo several optimizations so the best option can be selected for concreate applications. DNA was used as a model analyte and the media with the highest recovery were selected. The best results offered NEEO and PFEG agarose gels and Dyneema foamed polymer with recovery over 70%. Another interesting alternative are PDMS columns, with their open structure that allow concentration of large volume analytes such as microorganisms.
|
|
|
Temporary dwelling of migrants-reception and residential center
Bosák, Martin ; Dvořák, Miloš (referee) ; Nový, Alois (advisor)
The content of the thesis is an architectural study of the temporary accommodation of migrants and finding a suitable location on the territory of the city of Brno. The choice of land suitable for construction must meet not only the technical requirements but also take into account the sensitive public relation to this type of equipment. The location of the Malměřice-Obřany district in Brno, currently managed as a brownfield, meets all the requirements and contributes to the reclamation of urban space.
|
|
|
Temporary dwelling of migrants-reception and residential center
Vondráková, Kateřina ; Dvořák, Miloš (referee) ; Nový, Alois (advisor)
The theme of diploma thesis is design of reception center and residential center in Brno city. These asylum facilities are first two steps to proceeding for granting international protection. Both of these facilities provide accomodation and other services, such as provide of meals, social and psychological services, legal help or clients can take part in wide range of free-time activites. Designed complex is located at Červený kopec in Brno-Štýřice and it consists of 6 building divided into three parts - reception center, residential center and central structures used by the both facilities, such as administration, kitchen and maintenance services.
|
|
|
Evaluation of applicability of indirect photometric detection for chiral separations of selected carboxylic acids in dairy products
Dvořák, Miloš ; Zemanová, Jana (referee) ; Vespalcová, Milena (advisor)
In this diploma work is check possibility application indirect photometric detection for enantiomers separation lactic acids and beta-hydroxybutyric acid with capillary electrophoresis. As chiral selector is used vankomycin. Verifyed his ability partial separation lactic acid on antipode with using picric acid as vizualition anion in background electrolyte. Used was coated capillary. Application indirect photometric detection succeed. Chiral separation beta-hydroxybutyric acid wasn't successful. Hip roll by selection fit vizualization anions for purposes indirect photometric detection. Are measured their electrophoretic and spectrophotometric characteristics, for inquest compatibility use in capillary electrophoresis in relation to indirect photometric detection. From timed datums were to be you - nap optimal vizualizatin anions for others experimentation. According to ascertained and measured feature reflect be optimal eosine soluble in alcohol and bromophenol blue.
|
|
|
The content of allergenic aromatic compounds in chosen food types
Fidrichová, Ivana ; Dvořák, Miloš (referee) ; Vítová, Eva (advisor)
This thesis describes properties, origin, usage and methods of obtaining fragrances of vegetable origin, which are common part of food products. Although the aroma substances are not classified as the main group of allergens, in many cases there is a warning of their allergic potential. 26 crucial fragrance allergens and related restrictions are set by the European Cosmetic Regulations. There is no coincident regulation for food processing industry so far. The practical part dealt with identification of potential allergenic fragrances in randomly selected food products.
|
|
|
Application of polymer membranes in microextraction techniques for analysis of biological samples
Ryšavá, Lenka ; Diviš, Pavel (referee) ; Dvořák, Miloš (advisor)
The thesis presents experimental study on application of various polypropylene membranes (with different thicknesses, porosity and pore size) for direct coupling of membrane microextractions with capillary electrophoresis. No comprehensive study, which describes effect of these membrane parameters on extraction recoveries, was published in the past. Previous scientific works prefer application of 100 µm polypropylene membranes for their easy handling and satisfactory extraction efficiencies. Experimental part includes examination of selected polypropylene membranes as supported liquid membranes in-line coupled to capillary electrophoresis for analysis of basic drugs from complex samples. Membranes with three thicknesses (25, 100 and 170 µm) were tested. The highest extraction recoveries were achieved for the 25µm thick polypropylene membrane. Various pH conditions of donor and acceptor operational solutions were examined for extractions from real complex matrices (urine, plasma). The optimal extraction conditions were 10 mM NaOH as donor phase and 10 mM HCl as acceptor phase. 25µm membranes offer higher extraction recoveries, reduced consumption of organic solvents for membrane impregnation, similar mechanical stability and similar clean-up ability compared to thicker polypropylene membranes.
|
|
|
Application of microextraction techniques for analysis of biological samples
Lučaj, Martin ; Vespalcová, Milena (referee) ; Dvořák, Miloš (advisor)
This bachelor thesis deals with the analysis of basic drugs in biological samples by in line coupling of supported liquid membrane (SLM) to capillary electrophoresis (CE). The tITP method was included as an on-line preconcentration step to achieve better detection limits with ammonium acetate as the tITP stacker and acetic acid as the CE background electrolyte. The practical part of the thesis focuses on the optimization of the tITP and the SLM extraction conditions in the analysis of basic drugs in complex biological samples (human urine). The best analytical results were achieved with hydrodynamic injection of ammonium acetate for 15 s and basic drugs for 15 s. The donor was alkalised with 10 mM sodium hydroxide and acceptor was acidified with 10 mM hydrochloric acid. From the results, the in-line coupling of SLM extraction to CE and stacking by tITP is an efficient method allowing direct analysis of complex samples with improved sensitivity of the analytical method.
|
|
|
Preconcentration of ion compounds from sample by epitachophoresis
Kocianová, Vanda ; Dvořák, Miloš (referee) ; Voráčová,, Ivona (advisor)
Epitachophoresis is newly developed method, which allows to separate and concentrate analytes from large volumes of complex samples. Principle is based on isotachophoresis and utilize discontinuous electrolyte system. Different design of device is used, its round shaped and due to that acceleration of analytes zone migration occurs during separation towards centre of device and at the same time widening of zones happens. Focusation, concentration and separation of analytes between leading and terminating electrolyte progress from outer line of device towards its centre. It is necessary to stabilize this boundary to prevent mixing of leading and terminating electrolyte. Main target of this diploma thesis is optimization of epitachophoretic conditions, mainly electrolyte boundary stabilization options. Tested stabilizing media were agarose gels, foamed polymer disks and PDMS columns. All leading and terminating electrolyte boundary stabilizing media undergo several optimizations so the best option can be selected for concreate applications. DNA was used as a model analyte and the media with the highest recovery were selected. The best results offered NEEO and PFEG agarose gels and Dyneema foamed polymer with recovery over 70%. Another interesting alternative are PDMS columns, with their open structure that allow concentration of large volume analytes such as microorganisms.
|
|
|
Coupling of micro-electromembrane extraction to transient capillary isotachophoresis for the analysis of drugs in biological samples
Lučaj, Martin ; Pospíchal,, Jan (referee) ; Dvořák, Miloš (advisor)
The diploma thesis is focused on the development of in-line micro-electromembrane extraction (EME) coupled to capillary electrophoresis (CE) for the analysis of selected drugs in body fluids. Up to now, direct coupling of EME to CE has been demonstrated on diluted river samples only [1]. Although the published set-up has been implemented within a commercial CE it suffers from several drawbacks that can have a negative impact on the analysis of samples with higher complexity. The instrumental arrangement presented in this thesis eliminates these deficiencies. The experimental part is based on the optimization of fundamental extraction and separation conditions for the analysis of model basic drugs (nortriptyline, haloperidol, loperamide) with the use of transient isotachophoresis (tITP) principle. The extraction conditions were optimized for electro-driven transport of basic analytes from complex matrices (urine) through free liquid membrane followed by injection step utilized by electrokinetic supercharging (EKS), which focused target analytes into the CE capillary. Optimized conditions have been applied on blood in the form of dry blood spots, which are highly attractive samples in the current clinical analysis. The repeatability of the measurements was
|
|
|
Low-cost microextraction and preconcentration procedures for biomedical applications
Vašátko, Jan ; Diviš, Pavel (referee) ; Dvořák, Miloš (advisor)
This thesis focuses on low-cost microextraction techniques and their application for purification and preconcentration of biological samples, specifically on the experimental study of supported liquid membrane (SLM) extraction. The described microextraction technique uses commercially available filtration plates as the extraction units and allows the extraction of basic drugs from biological samples of urine and blood (in the form of dried blood spots). The experimental part includes the optimization of microextraction conditions of basic drugs from real samples through a SLM coupled in-line to lab-made capillary electrophoresis. The basic optimization of microextraction conditions involved selecting the appropriate organic phase for membrane impregnation (1:1 mixture of ENB and DHE), appropriate agitation speed for sample convection during extraction (1000 rpm), and optimal ratio of donor to acceptor volumes for high preconcentration of the analytes (400:15 µL). After basic optimization, the effect of donor alkalization with NaOH on extraction recovery (ER) was investigated. For all matrices used (saline solution, undiluted human urine samples, human capillary blood eluted from dry blood spots with deionized water), the highest ER values were achieved using a neutral donor and an acidic acceptor. The extraction time (60 minutes) was optimized based on the time profile of the microextraction for 120 minutes. This optimized microextraction method is suitable for the determination of basic drugs in real matrices with sufficient sample clean-up, preconcentration and ER values.
|
guest ::
RSS feed.