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Experimental study on the release of active ingredients from gel matrices
Volhinava, Anastasiya ; Enev, Vojtěch (referee) ; Sedláček, Petr (advisor)
This thesis deals with the characterization of hydrogels containing humic substances and salicylic acid. Experimental study of the transport of active substances was performed from the gel matrix over the skin and synthetic membranes. During this work was writing literature review focused on the use of gels with humic substances in cosmetic, medical and pharmaceutical industries. The model humic hydrogels was prepared with salicylic acid and their characterization by basic methods of material analysis. These basic methods were and visual assessment of consistency during the preparation and rheology. The study of the release of active and humic substances was performed due to the vertical diffusion cells. The amount of released humic substance was characterized by UV-VIS method and the amount of released salicylic acid from gel matrix was determined by HPLC.
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Micropollutants in water resources and ways of their elimination
Lukášová, Daniela ; Látal,, Milan (referee) ; Biela, Renata (advisor)
The diploma thesis deals with micro-fuels in drinking water sources and their subsequent removal. In the thesis mainly pesticides and pharmaceuticals are described. The reader is first introduced to the most common pesticides occurring in water and their consumption. Drugs are described in a similar context. In addition, there are practical studies on the occurrence, degradation and removal of micro-pollutants from water. The final thesis is a laboratory experiment dealing with the removal of salicylic acid from water by filtration through the filtration material Bayoxide E33 and activated carbon. The thesis describes the procedure and results of the experiment.
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Material characterization of novel hydrogels containing humic substances intended for pharmaceutical and cosmetic applications
Pavlicová, Renata ; Weidlich, Tomáš (referee) ; Sedláček, Petr (advisor)
This thesis is focused on the development and characterization of hydrogels containing humic substances with possible use in cosmetic and pharmaceutical industries. This work follows on the bachelor thesis, theoretical and experimental part is based on already acquired knowledge. The aim of this work was to develop a literature review focusing on the potential use humic gels in practice and also to enhance the consistency of other active ingredients. Based on this literature review, the main aim was to prepare model humic hydrogels with selected active ingredients and their characterization by basic methods of material analysis. These basic methods were especially rheology and visual assessment of consistency during the preparation, then the samples were subjected process of drying and swelling. Experimental results showed considerable influences during the preparation and composition of each sample, which then reflected in their structure and consistency. Furthermore, it was found that the suitable composition and combination of ingredients form hydrogels acceptable characteristics for further use in cosmetic or pharmaceutical applications.
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Use of copolymer polyhydroxyalkanoates in development of intelligent packaging
Kreuzerová, Monika ; Kalina, Michal (referee) ; Sedláček, Petr (advisor)
This bachelor thesis deals with the preparation and characterization of copolymers P(3HB-co-4HB). The theoretical part discusses polyhydroxyalcanolates (PHA), where their structure, properties and synthesis are described and subsequently the selected copolymers, which contain monomeric units 3HB, are listed. Furthermore, the review part is processed for the current state of the issue, which states the use of copolymers PHA and current research work on the incorporation of active substances into copolymers. The aim of this work was to characterize and compare the created P(3HB) and P(3HB-co-4HB) foils with a 4HB monomeric unit of 65,25 % and 43,61 % and subsequently determine the potential of foil usability as intelligent packaging materials. First, PHA were subjected to gas chromatography, SEC-MALS, FTIR and DSC analysis. In the second part of the thesis, the permeability of foils to water vapor and the release of model active substances from PHA foils was studied. For this purpose, two active substances (curcumin and salicylic acid) were selected, which were incorporated into a film of homopolymer P(3HB) and two copolymers with a proportion of 4HB of 65,25 % and 43,61 %. In foils prepared from copolymers, the active substances diffusion was faster than in P(3HB). Within the copolymers, P(3HB-co-43,61%4HB) released substances at a higher speed, due to the greater crystallinity of a copolymer containing 65,25 % 4HB.
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Development of Electrochemical Thin-layer Degradation Cell for Oxidation Stress Testing of Active Pharmaceutical Ingredients
Šefčík, Martin ; Kubíčková, Anna (advisor) ; Coufal, Pavel (referee)
In this thesis, the oxidation conditions in a new electrochemical "thin-layer" flow-through cell for the study of the oxidative degradation of active pharmaceutical ingredients were optimized. In this field, it is an innovative approach to studying the oxidation properties of substances. The cell was manufactured using 3D printing technology. Oxidation was carried out in a two-electrode arrangement with a working boron-doped diamond electrode (BDDE) and an auxiliary stainless steel electrode. Optimization of conditions was performed using salicylic acid as a model active pharmaceutical ingredient. The electrochemical approach was used to degrade this active pharmaceutical ingredient by the required approximately 20% of the original amount in only 2.3 min. Thus, the degradation time was significantly reduced compared to the oxidative stability stress tests of active pharmaceutical ingredients commonly used today. Two major degradation products were observed, namely gentisic acid and 2,3-dihydroxybenzoic acid. The degradation products obtained by electrochemical oxidation and chemical oxidation using hydrogen peroxide are identical.
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Dissecting the effects of salicylic acid on redox balance in plant cells using biochemical and fluorescent imaging techniques
Růžičková, Gabriela ; Burketová, Lenka (advisor) ; Janda, Martin (referee)
Topic of bachelor thesis is plant immunity, specifically it focuses on salicylic acid, reactive oxygen species, it also analyses hox salicylic acid effects formation of reactive oxygen species and which proteins are involved in this biosynthesis. Also in this thesis is described basic methods for measuring of reactive oxygen species, what are advantages, disadvantages, how they work and what they can be used for. Salicylic acid is one of phytohormones involved in immune reaction in plant defence, this thesis is describing salicylic acid signalling, associated proteins and overall effect on plant. Reactive oxygen species have wide framework of action in organisms, they can be called double-edged sword, they can help plant, but also, they can harm depending on their concentration and regulation of their forming, the problem of their quenching is also described in this thesis - their formation, antioxidants, effect on plant immunity. Chapter about measuring methods is divide into three parts - fluorescence methods, chemiluminescence methods and spectrophotometric (histochemical) methods. Key words: salicylic acid, reactive oxygen species, plant immunity, plant stress, phytohormones
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The study of the electrochemical and chemical oxidative degradation of salicylic and acetylsalicylic acid
Tonnerová, Barbora ; Kubíčková, Anna (advisor) ; Křížek, Tomáš (referee)
The aim of this Thesis was to study the degradation of salicylic acid by the electrochemical oxidation. The electrochemical oxidation of salicylic acid was compared to the electrochemical oxidation of acetylsalicylic acid. Two electrochemical cells were tested - batch cell and thin- layer flow-cell. The newly developed and validated method of ultra-high performance liquid chromatography has been used to analyse the degradation products, salicylic acid and acetylsalicylic acid. The optimal analysis was made by the Kinetex column C18 (2,1 x 100 mm; 1,7 µm) and mobile phase with two components - acetonitrile and water with addition of 0,1% formic acid. These two components of the mobile phase were mixed by the gradient program from 10 % to 60 % (v/v) acetonitrile. The mobile phase flow was set to 0,3 ml min-1 and the volume of injection was 2 µl. The detection was performed by photodiode array detector at the wavelength 240 nm. Total time of the analysis was 11 minutes. The electrochemical degradation has been studied by an anodic oxidation in a flow cell with a boron-doped diamond (BDD) anode and a stainless-steel cathode. The samples of salicylic acid and acetylsalicylic acid was dissolved in the ammonium acetate, concentration 200 mmol dm-3 at pH=4,0. The 20 % oxidation rate of salicylic acid was...
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Use of copolymer polyhydroxyalkanoates in development of intelligent packaging
Kreuzerová, Monika ; Kalina, Michal (referee) ; Sedláček, Petr (advisor)
This bachelor thesis deals with the preparation and characterization of copolymers P(3HB-co-4HB). The theoretical part discusses polyhydroxyalcanolates (PHA), where their structure, properties and synthesis are described and subsequently the selected copolymers, which contain monomeric units 3HB, are listed. Furthermore, the review part is processed for the current state of the issue, which states the use of copolymers PHA and current research work on the incorporation of active substances into copolymers. The aim of this work was to characterize and compare the created P(3HB) and P(3HB-co-4HB) foils with a 4HB monomeric unit of 65,25 % and 43,61 % and subsequently determine the potential of foil usability as intelligent packaging materials. First, PHA were subjected to gas chromatography, SEC-MALS, FTIR and DSC analysis. In the second part of the thesis, the permeability of foils to water vapor and the release of model active substances from PHA foils was studied. For this purpose, two active substances (curcumin and salicylic acid) were selected, which were incorporated into a film of homopolymer P(3HB) and two copolymers with a proportion of 4HB of 65,25 % and 43,61 %. In foils prepared from copolymers, the active substances diffusion was faster than in P(3HB). Within the copolymers, P(3HB-co-43,61%4HB) released substances at a higher speed, due to the greater crystallinity of a copolymer containing 65,25 % 4HB.
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The characterisation of organ-specific phytohormone responses to nutrient deficiency and biotic stress
Kramná, Barbara ; Vaňková, Radomíra (advisor) ; Hronková, Marie (referee) ; Plíhalová, Lucie (referee)
Abiotic and biotic stresses lead to crop yield losses and ultimately negatively affect agriculture production. Elucidation of the mechanisms of plant stress responses and their regulation could help to understand plant defence and improve stress tolerance. Phytohormones stand behind both plant growth and developmental changes as well as stress signalling. This thesis summarises the results published in two articles focused on phytohormone dynamics in response to abiotic and biotic stresses, namely phosphate shortage and Plasmodiophora brassicae infection. A review article focuses in depth on strigolactones as master regulators of phosphate deficiency responses. The main emphasis is put on organ-specific reactions and exogenous phytohormone treatment with the potential to convey stress tolerance. In the case of phosphate shortage, the universal reaction in all organs was a decrease in active cytokinin trans-zeatin and gibberellin GA4 with a concurrent elevation of abscisic acid. Also, the high- affinity phosphate transporters (PHT1;4 and PHT1;7) exhibited increased gene expression within the whole plant. Shoot apical meristems showed numerous changes in gene expression and were the most affected organ during the lack of phosphate. Only in roots, we observed a substantial elevation of low active...
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Use of Fenton Reaction for Drug Degradation in the Ecosystem
Tomešová, Lenka ; Smrček, Stanislav (advisor) ; Břichnáčová Habartová, Věra (referee)
The elimination of unwanted substances from the ecosystem can be accomplished by advanced oxidation processes (AOP). AOPs are used preferably in treatment of wastewater. One of the AOP's methods is Fenton's reaction. The degradation of drug residues by this reaction was the aim the project. The experiments were focused on finding possible degradation products, which could be much more hazardous than parent compounds. The study was primarily concerned with non-steroidal anti-inflammatory drugs (acetaminophen, diclofenac, ibuprofen, naproxen and salicylic acid) and antiepileptic carbamazepine. The complete decomposition of tested compounds was not observed by using HPLC and MS analysis. The products of decomposition were found in reaction mixture, in case of diclofenac dechloration of aromatic ring occurred. In cases of most compounds with exception of acetoaminophen and salicylic acid the reaction led to the formation of more polar products than parent compounds. The results imply that even more advanced oxidation processes do not cause complete destruction of organic compounds. Key words: Fentons reaction, drug residues, acetaminophen, diclofenac, ibuprofen, carbamazepine, naproxen, salicylic acid.
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