National Repository of Grey Literature 242 records found  1 - 10nextend  jump to record: Search took 0.01 seconds. 
Host-guest systems for efficient infrared solid-state emission
Rottenberg, Vojtěch ; Smolka, Rastislav (referee) ; Kratochvíl, Matouš (advisor)
The goal of this bachelor thesis is to compile a brief research on solid-phase fluorescence, to find suitable molecules for the preparation of host-guest systems that exhibit high quantum yields of solidphase fluorescence in the infrared region and to analyze them. These systems consist of a predominant molecule (host) that exhibits high quantum yields of fluorescence and a quantitatively less abundant molecule (guest) that exhibits fluorescence in the infrared part of the electromagnetic spectrum. The following molecules were chosen: (E)-N,N-diphenyl-4-(2-(5'-vinyl-[1,1':4',1''-terphenyl]-2'- yl)vinyl)aniline (–V) and (E)-5'-(4-(diphenylamino)styryl)-[1,1': 4',1''-terphenyl]-2'-carbonitrile (–CN) as a guest molecule and (E)-2-((5'-(4-(diphenylamino)styryl)-[1,1':4',1''-terphenyl]-2'- yl)methylene)malononitrile (–DCV) as a guest molecule. For sample analysis, emission and excitation spectra were measured using a fluorophore, quantum yields using an integrating sphere, and fluorescence lifetimes using the time-correlated single photon counting (TCSPC) method. From the spectral analyses and quantum yields, it was determined that the molecule (E)-5'-(4- (diphenylamino)styryl)-[1,1':4',1''-terphenyl]-2'-carbonitrile (–CN) is a suitable guest molecule, (E)-2- ((5'-(4-(diphenylamino)styryl)-[1,1': 4',1''-terphenyl]-2'-yl)methylene)malononitrile (–DCV) is not a suitable guest molecule and the suitability of using (E)-N,N-diphenyl-4-(2-(5'-vinyl-[1,1':4',1''- terphenyl]-2'-yl)vinyl)aniline (–V) as a guest molecule is inconclusive.
Veterinary tissue engineering materials
Lavrinčíková, Veronika ; Krouská, Jitka (referee) ; Venerová, Tereza (advisor)
This bachelor thesis focuses on materials that could be used in veterinary tissue engineering, including hydroxyapatite, which is one of the main components of PerOssal® (51,5 % hydroxyapatite, 48,5 % calcium sulphate), which was used in the experimental part of this thesis. The behavior of the PerOssal® pellet in an aqueous environment was observed, which resulted in disintegration into particles. These particles were subsequently analyzed using DLS and SEM methods and ranged in sizes from micrometers for calcium sulfate to nanometers for hydroxyapatite. The main purpose of this thesis was to observe the diffusion characteristics of hydroxyapatite using Rhodamine 6G and PerOssal®. It was found that over 18 days, the pellet gradually released fluctuating concentrations of the fluorescent dye without spontaneously disintegrating, with the most intense release occurring during the first two days of the experiment. PerOssal® has potential use in veterinary medicine, not only as a bone tissue substitute, but also due to its ability to act as a carrier. The pellet can absorb an aqueous drug solution into its volume and subsequently releasing it in small doses over an extended time.
Design of Portable Fluorescence Immunoassay Analyzer
Filková, Adriana ; Sládek, Josef (referee) ; Fridrichová, Eva (advisor)
The subject of this bachelor's thesis is a design of a portable fluorescence immunological analyzer for laboratory and healthcare facilities. The main requirements encompassed durability, ergonomics, and easy sample manipulation. Based on technical and design analysis, a custom design was developed, incorporating a stand for holding a testing mico tube, automatic slot opening, a touchscreen display, and an on/off button. The lateral sides of the product are ergonomically rounded and feature anti-slip grooving. To enhance durability, the touchscreen display is recessed into the top surface of the analyzer. The design of the resulting proposal is non-intrusive and meets the environmental conditions for which it is intended.
Effect of freeze-drying conditions on the hydrophobic interaction between native hyaluronan and fluorescent probe
Říha, Karel ; Venerová, Tereza (referee) ; Enev, Vojtěch (advisor)
The biopolymer native hyaluronan possesses the amphiphilic character of its molecule. Which means that it contains both a hydrophilic and a hydrophobic part. This character of the molecule favors interactions between hydrophobic ligands and hydrophobic parts of the chain, making hyaluronan one of the compounds potentially suitable as drug carrier systems. The aim of this bachelor thesis was to prepare a carrier system based on hyaluronan and model hydrophobic compounds (fluorescent probes). The fluorescent probe we used was pyrene. Furthermore, the work was focused on the study of lyophilization conditions, which would lead to the actual influence of hydrophobic interactions between the substances we used. The main techniques that served us to verify the effectiveness of lyophilization (in the sense of supporting the creation of a hydrophobic effect between individual hyaluronan chains) were: thermogravimetric analysis, fluorescence spectrometry, and last but not least, infrared spectroscopy with Fourier transformation.
Organic luminophores with long wavelenght emission
Kolaříková, Adéla ; Kratochvíl, Matouš (referee) ; Vala, Martin (advisor)
This bachelor thesis studies the possibility of achieving intense fluorescence in the red region of the spectrum using Förster resonance energy transfer (FRET) in nanoparticles. First, the optical properties of organic molecules that could be suitable for the creation of a so-called host-guest (HG) system consisting of an acceptor-donor pair were studied. The molecules studied were based on derivatives of diphenylstilbene containing the electron-donor group diphenylamine (DPA-DPS), which is linked to a differing electron-acceptor group via a -conjugated double bond system. The acceptor groups used, i.e., indandione (-IOO), vinyl ( V) and di(methoxycarbonyl)vinyl (-V(COOMe)2), differ from each other in structure and polarity, which was reflected by a change in the position of the fluorescence spectrum. In the HG systems studied, DPA-DPS-IOO always served as the guest (G1) and DPA-DPS-V and DPA-DPS-V(COOMe)2 always served as the host (H1 or H2). Nanoparticles from these substances (G1H1 and G1H2) were prepared by the nanoprecipitation method. FRET was observed for both of these systems. Upon excitation of the matrix, the energy was transferred to the guest G1, which subsequently fluoresced in the long-wavelength region. Furthermore, an increase in the quantum yield of the guest fluorescence was also observed for the nanoparticles formed from the G1H2 system, from 7% (powder) and 3.1% (nanoparticles) to 14% compared to both the powder form and nanoparticles formed from the guest alone. No increase in the quantum yield of guest fluorescence was observed for the nanoparticles of the G1H1 system. The results indicated that FRET can be an effective tool in developing nanoparticles exhibiting intense long-wavelength fluorescence for imaging.
Synthesis of triblock terpolymers as a tool for preparation of smart drug delivery nanosystems
Orságh, Martin ; Uchman, Mariusz Marcin (advisor) ; Fernandez Alvarez, Roberto (referee)
In this thesis, we describe the synthesis and self-assembly of new photo-responsive triblock terpolymers by RAFT polymerization. These triblock terpolymers were characterized by GPC, NMR and IR spectroscopy. The resulting nanoparticles were characterized by DLS, SAXS and Cryo-EM. To avoid problems with RAFT polymerization of the photo-responsive monomer o- nitrobenzyl acrylate, we used naphthacyl methacrylate, a new RAFT-polymerizable photo- responsive monomer. In addition, we used phenylboronic acid moieties to conjugate model drugs with our triblock terpolymers via dynamic covalent bonding and studied stimuli-triggered release of a model drug-like compound, Alizarin Red S. Our results showed that naphthacyl methacrylate is indeed polymerizable by RAFT and that such polymers retain photo-responsive properties. We were also able to bind Alizarin Red S to the polymer via boronate ester linkage and trigger its release by dopamine or fructose addition, both of which are biologically relevant compounds. Therefore, our photo- and diol-responsive nanoparticles open up opportunities for developing new drug-delivery systems.
Application of (chir)optical analytical methods in the characterization of nonracemic helically chiral aromatics
Vilím, Vojtěch ; Hraníček, Jakub (advisor) ; Dian, Juraj (referee)
This master thesis is focused on preparation and characterization of thin layers for organic electronics forming a binary system, composed of achiral small conductive molecules (TIPS-pentacen) and chiral helicenes with various electronic density of their aromatic scaffold. Using organic electronics is innovative approach to manufacture electronic devices and compensate disadvantages of inorganic materials-based electronics. Induction of chirality into achiral organic electronics brings new possibilities for application in optical spintronics, optical quantum information processing and many others. Key words: thin layer, helicenes, circular dichroism, organic electronics
Optical characterization of supramolecular complexes of selected organic fluorophores with cyclodextrins
Haiklová, Simona ; Dian, Juraj (advisor) ; Červený, Václav (referee)
The content of this thesis is the optical characterization and determination of the strength of supramolecular interaction of selected organic fluorophores and cyclodextrins (CD) using the stability constant with optical methods: UV-Vis absorption and fluorescence. Two series of fluorophores differed in the presence of groups with two positive charges, and two types of cyclodextrins (-CD a -CD) with different cavity sizes were chosen for the study. Fluorophores with charged end groups can be efficiently bound by electrostatic interaction on solid surfaces of suitable chemical composition or thin films with an excess of negative charge and thus immobilized by a very strong interaction on a given support. These prepared surfaces or layers can then be used for the optical detection of chemical substances. The aim of this work was to determine the influence of cyclodextrin cavity size, the presence of a charged anchor, and solution pH on the supramolecular interaction of the studied systems and evaluate the application possibilities of the studied systems for optical chemosensors. In the presented thesis, the change in optical absorption and fluorescence intensity of four pairs of fluorophores: PRODAN, RhB, RhB-Si, DANSA, and their derivatives with a charged anchor was studied during supramolecular...
Stimuli - responsive nanoparticles with boronic ester linkages as a potential carrier for drug delivery
Hlavatovičová, Eva
This thesis deals with the post-polymerization functionalization of a pH-responsive poly(styrene)-b-poly(4-vinyl pyridine)-b-poly(ethylene oxide) triblock terpolymer with stimuli responsive and diol-binding 2-bromomethyl-4-fluorophenylboronic acid and 2- bromomethyl-phenylboronic acid suitable for biomedical applications. A reproducible method of quaternization of poly(4-vinyl pyridine) block with prescriptible quaternization ratio was developed and the reaction yield was analyzed by 11 B, 1 H NMR and infrared spectroscopy. A reproducible self-assembly protocol for stable nanoparticles from functionalized stimuli-responsive triblock terpolymer was found, and the nanoparticles were studied by static, dynamic and electrophoretic light scattering, and cryogenic transmission electron microscopy. Fluorescence and UV-VIS spectroscopy measurements were performed for description of boron-ester linkages formation and hydrolysis with model drug Alizarin as a study of encapsulation and release reactions together with sugar sensing reactions for potential drug delivery.

National Repository of Grey Literature : 242 records found   1 - 10nextend  jump to record:
Interested in being notified about new results for this query?
Subscribe to the RSS feed.