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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Využití vybraných zemědělských a potravinářských odpadů k výrobě funkčních potravin a biomateriálů

Urban, Marián January 2013 (has links)
This dissertation thesis describes utilization of agricultural and food processing waste and intermediate materials for manufacturing of functional food and bio-materials. The aim of this study is to develop new procedures to process food and agricultural byproducts in order to create modern products and materials with higher added value. The focus here is especially on food supplements, nutraceuticals, bio-materials for health industry and pharmacology. Examples can be substances for drug delivery or substances for controlled release of active ingredients. Examples of such products are cyclodextrins, chitosan, chitin-glucan complex and glutathion.
2

vývoj fluorosenzoru na bázi chemicky modifikovaných elektroluminiscenčních diod. / development of fluorosenzor based on chemically modified electroluminescence diods.

Blažková, Ivona January 2012 (has links)
Luminescence sensors based on LED were prepared by modification of LED poly- carbonate surface and following binding of luminescence dyes on this surface. Two methods of modification were utilized. The first one was the oxidation of the surface yielding free carboxylic groups. Such modified LEDs were then covered by cationic cresyl violet dye. The second modification consisted of nitration and consequent reduction to free amino groups followed by binding of anionic sulforhodamine dye. The stability of emission and the stability of dye binding were studied. Then, the response of constructed sensors to toluene as analyte in gas and liquid phase was measured.
3

Stanovení konstant stability komplexů s nabitými cyklodextriny kapilární zónovou elektroforézou / Determination of stability constants of charged cyclodextrine complexes by capillary electrophoresis

Beneš, Martin January 2010 (has links)
Martin Beneš Determination of stability constants of charged cyclodextrin comlexes by capillary electrophoresis Abstract Stability constant characterizes binding interaction between an analyte and complexation agent. These interactions play very important role in separation processes of, in other way undistinguishable, compounds, e.g. enantiomers. The most widely used complexation agents are cyclodextrins. Affinity capillary electrophoresis (ACE) belongs to methods suitable for the determination of stability constants. The stability constant is determined from the dependence of the effective mobility of analyte on the increasing concentration of complexation agent in background electrolyte (BGE). If charged CDs are used, the attention must be paid not only to viscosity of the BGE and to the influence of Joule heating on the temperature in the capillary but also to the increasing ionic strength. The thermodynamic stability constants of R,R- and S,S-hydrobenzoin and R- and S-(3-brom- 2-methyl-1-propanol) with cationic modified β-cyclodextrin: 6-monodeoxy-6-mono(3- hydroxy)propylamino-β-cyclodextrin hydrochlorid (PABCD) were determined by affinity capillary electrophoresis. The average temperature (25řC) of the BGE in the capillary was kept constant. This was achieved by decreasing of the cassette temperature...
4

Syntéza sulfanylaminoderivátů cyklodextrinů a počítačová simulace tvorby jejich komplexů / Synthesis of sulphanylaminoderivatives of cyclodextrines and computational simulations of their complexes formation

Provazníková, Adéla January 2016 (has links)
This master thesis deals with synthesis of 6I -N-monosubstituted β-CD bearing a linear spacer of various lenghts containing disulfidic bond and terminated by amine. Whole series was succesfully prepared by nucleophilic substitution of toluenesulfonyl group on tosyl β-CD by a spacer's amine group. In case of the shortest spacer (cystamine) 35 % yield was achieved. Synthesis of β-CD derivatives using longer and more lipophilic spacer derived from di-, tri- and tetraethylenglycol yielded 66 to 85 %. The oligoethylene spacers were prepared by standard chemical modifications. A separation method using n-butanol elution mixtures was optimized for isolation of β-CD derivatives. To better understand the β-CD derivative behavior in solution, molecular dynamics (MD) computations were used. The synthetized species were intended to be used for fluorescent sensor construction. For the same reason the inclusion of small organic molecules in β-CD cavity was studied with molecular dynamic simulations. MD method for computation of relative binding energy was optimized and gave values of right sign and order of magnitude.
5

Komplexační rovnováhy beta-blokátorů v CZE / Complex equilibriums of beta-blockers in CZE

Kanizsová, Lívia January 2016 (has links)
Drugs used in the pharmaceutical industry often occur as a mixture of several isomers with a different biological activity. In a case that some isomer provides an undesirable side effect, it is important to separate it from the mixture and check the chiral purity of a drug. Capillary zone electrophoresis plays a significant role in chiral separations. A different affinity of isomers to complexation reagent is used for their separation from each other. The extent of their interaction is characterized by the complexation constant. Most commonly the cyclodextrins are used for the chiral separations of β-blockers and they could be in neutral or charged form. They probably interact with them through the creation of inclusion complexes. A successful baseline enantioseparation of all the β-blockers that have been studied, labetalol, pindolol, alprenolol and atenolol, was provided by using the background electrolyte containing charged cyclodextrins. The highest resolution of peaks was observed using sulfated cyclodextrins.
6

Studium komplexace vortioxetinu cyklodextriny a jeho stanovení kapilární elektroforézou / Study of vortioxetin complexation by native cyclodextrins and its determination using capillary electrophoresis

Počtová, Žofie January 2017 (has links)
In this master thesis, the formation of supramolecular complexes between vortioxetine active substance and cyclodextrins (α, β, γ) is examined and the stability constants of these complexes are determined. The stoichiometric ratios of cyclodextrin and vortioxetine 1:1 and 2:1 are considered. The results suggest that the 1:1 ratio of cyclodextrin and vortioxetine is more accurate for each of used cyclodextrins and that the strongest interaction is between vortioxetine and β-cyclodextrin. Further, a method for vortioxetine assay in a tablet is developed by using non-aqueous capillary electrophoresis technique. The precision, accuracy, and robustness are validated and the values of detection and quantification limits are determined. This method can be used as a verification method for the results obtained by HPLC as the separation principle is different in capillary electrophoresis. Also, the stability of vortioxetine as a pure powder and as a mixture with excipients is examined under the conditions of elevated temperature and humidity.
7

Karboranové strukturní bloky v medicinální chemii / Carborane structural blocks in medicinal chemistry

Nekvinda, Jan January 2018 (has links)
This work deals with carborane and metallacarborane clusters, in terms of their fundamental chemistry and complexation with cyclodextrins, and in the context of emerging pharmacophores applicable in medicinal chemistry. Arguably, the most important part of this work is the preparation of cobalt bis(dicarbollide) sulfamide derivatives. The sulfamido group is attached to the metallacarborane carbon vertex by an alkyl chain that may be modified in its length. This was accomplished by, firstly, the abstraction of the acidic hydrogen, located on the {CH}-vertex from the metallacarborane, by reaction with lithium base, followed by, secondly, reaction with electrophilic agents (PFA, oxirane and oxetane), which leads to a cascade of reactions to give the desired sulfamide derivatives. These compounds were then tested by collaborators in other institutes for in vitro and in vivo activity towards Carbonic Anhydrase IX (CA IX), which is an enzyme associated with tumour growth. In vivo tests on mice have shown that these types of substances are able to effectively reduce tumour size by 30%. The synthetic research continued with the preparation of sulfonamide compounds of the isomers of the carborane series. The reactions began exclusively with propylhydroxy carborane starting materials, which provide optimum...
8

Karboranové strukturní bloky v medicinální chemii / Carborane structural blocks in medicinal chemistry

Nekvinda, Jan January 2018 (has links)
This work deals with carborane and metallacarborane clusters, in terms of their fundamental chemistry and complexation with cyclodextrins, and in the context of emerging pharmacophores applicable in medicinal chemistry. Arguably, the most important part of this work is the preparation of cobalt bis(dicarbollide) sulfamide derivatives. The sulfamido group is attached to the metallacarborane carbon vertex by an alkyl chain that may be modified in its length. This was accomplished by, firstly, the abstraction of the acidic hydrogen, located on the {CH}-vertex from the metallacarborane, by reaction with lithium base, followed by, secondly, reaction with electrophilic agents (PFA, oxirane and oxetane), which leads to a cascade of reactions to give the desired sulfamide derivatives. These compounds were then tested by collaborators in other institutes for in vitro and in vivo activity towards Carbonic Anhydrase IX (CA IX), which is an enzyme associated with tumour growth. In vivo tests on mice have shown that these types of substances are able to effectively reduce tumour size by 30%. The synthetic research continued with the preparation of sulfonamide compounds of the isomers of the carborane series. The reactions began exclusively with propylhydroxy carborane starting materials, which provide optimum...
9

Syntéza cyklodextrinových derivátů pro organokatalýzu / Synthesis of cyclodextrin derivatives for organocatalysis

Chena Tichá, Iveta January 2019 (has links)
Synthesis of cyclodextrin derivatives for organocatalysis This doctoral thesis examines the preparation of new cyclodextrin (CD) derivatives suitable for organocatalysis. The aim of this work is to prepare monosubstituted and disubstituted CD derivatives as organocatalysts for different types of enantioselective reactions potentially performed in water. In addition, disubstituted CD derivatives require considering the potential mixture of regioisomers and pseudoenantiomers. Thus, this thesis is divided into several sections - preparation of CD precursors and derivatives for organocatalysis, preparation of pure regioisomers and pseudoenantiomers of disubstituted CDs and final application of CD derivatives in enantioselective reactions. Furthermore, this thesis also focuses on the molecular modeling of the prepared CD derivatives and on their catalytic activity in silico. The first section covers the preparation of new disubstituted CD precursors as pure regioisomers for organocatalysts, specifically to develop a new method for the preparation of heterodisubstituted AC regioisomers on the primary rim of α-CD. This section also includes the determination of the regioisomer ratios of common α-CD intermediates disubstituted on the primary rim to evaluate their potential as precursors in organocatalysis....
10

Charakterizace samoorganizujících se molekul a jejich využití v kapilární elektroforéze / Characterization of self-assembling molecules and their application in capillary electrophoresis

Hodek, Ondřej January 2015 (has links)
This diploma thesis deals with application of newly synthesized α-cyclodextrins derivatives, 2I -O-cinnamyl-α-cyclodextrin and 3I -O-cinnamyl-α-cyclodextrin, in capillary electrophoresis. Their unique feature lies in formation of cyclodextrin aggregates in an aqueous solution by inclusion of phenyl moiety of one molecule into cavity of another one. The influence of addition of 2I -O-cinnamyl-α-CD and 3I -O-cinnamyl-α-CD to background electrolyte (BGE) and its impact on effective mobilities of eighteen selected analytes were tested. Nine analytes were measured in the form of cations (aniline, antipyrine, L-histidine, D,L-tyrosine, D,L- phenylalanine, N-(1-naphtyl)ethylenediamine, 4-nitroaniline, p-aminoaceto-phenon and tyramine) and nine in the form of anions (N-acetyl-D,L-phenylalanine, N-acetyl-D,L-tryptophan, N-benzoyl-D,L-phenylalanine, N-boc-D,L-tryptophan, N-FMOC-D,L-valine, N-FMOC-alanine, N-FMOC-D,L-leucine, D,L-3-phenyllactic acid and (R)-(-)-mandelic acid). Electrophoretic mobilities of cations were tested in BGE at pH 2.2 and anions at pH 8.0. The measurements were conducted at 25 and 50 řC. At the beginning the buffer containing 2.5 mM TRIS was adjusted with phosphoric acid to pH 2.2. However, it was found, that phosphate anions might enter cyclodextrin cavity and disable potential...

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