National Repository of Grey Literature 58 records found  beginprevious21 - 30nextend  jump to record: Search took 0.02 seconds. 
The use of high-performance separation techniques for monitoring the bioaccumulation of selected micropollutants in plants of model root treatment plants
Modroczká, Karin ; Sobotníková, Jana (advisor) ; Coufal, Pavel (referee)
This bachelor's thesis deals with the determination of ibuprofen in model root refineries from Phalaris arundinacea extracts. The goal was to find out if the plant is able to accumulate ibuprofen from the aqueous solution which was added to the plant. A HPLC method with UV/VIS detection was also optimized to determine the ibuprofen content. A C18 column (4.6 mm × 150 mm × 3.5 µm) was used to analyse the samples. An isocratic program was used, in which the mobile phase consisted of methanol and an aqueous acetic acid solution of pH = 3,27. As part of the validation of the method, the repeatability, robustness, and yield (which was 99,04 %) of the method were verified. Furthermore, the linearity of the method, which was from 0,01 mg ml-1 to 2,0 mg ml-1 , the limit of detection (LOD = 0,049 mg ml-1 ) and the limit of quantification (LOQ = 0,16 mg ml-1 ) were determined. After the validation of the method, we can claim that the method is accurate, because the values of the relative standard deviations did not exceed 2 %. Infrared spectroscopy was used to verify the purity of ibuprofen batches. Last but not least, it was proven that Phalaris arundinacea has the ability to accumulate ibuprofen from an aqueous solution. Keywords: HPLC, ibuprofen, Phalaris arundinacea, root wastewater treatment plant,...
Interactions of pharmaceuticals with fulvic acids – calorimetric study
Papko, Nadezhda ; Sedláček, Petr (referee) ; Klučáková, Martina (advisor)
Tato diplomová práce se zaměřuje na studium interakcí mezi půdní organickou hmotou a vybranými léky pomocí izotermické titrační kalorimetrie. V rámci experimentu byly použity tři fulvinové kyseliny a léky: ibuprofen, diclofenac a sulfapyridine. Vybrané léky a fulvinové kyseliny byly rozpouštěné v roztocích NaCl a MgCl2, jelikož kovové ionty jsou přítomny v organickém materiálu půdy. Mobilita léčiv závisí na sorpci, což je interakce mezi léčivy a půdními částicemi. Faktory ovlivňující sorpční chování zahrnují vlastnosti léčiv, půdy a enviromentální podmínky. Během bakalářské práce podražilo optimalizovat metodu ITC pro daný studiu, což usnadnilo experimentální práce a zlepšilo vyhodnocení dat. Pomocí metody byli stanovené tepelné efekty (naměřené a porovnané) interakcí mezi fulvinovými kyselinami a léky.
Humic substances as modifiers of the transdermal absorption of active phasrmaceutical ingredients
Blahuš, Petr ; Klučáková, Martina (referee) ; Sedláček, Petr (advisor)
This thesis deals with the influence of humic substances on the transdermal penetration of the analgesic drug ibuprofen. Analgesics in the form of oral administration have major side effects. Thanks to topical preparations, side effects could be reduced and also bring a number of other benefits. The problem in the development of a transdermal form of the drug is the very effective barrier capacity of the human skin. Therefore, a lot of research is focused on the search for various accelerators that can improve its properties due to interaction with the drug. In the future, such substances could also include humic acids, which have a long tradition of use in a number of therapeutic approaches, and recently examples of their use in human medicine are increasingly appearing. The research was focused on the diffusive transport of sodium ibuprofen and its acidic counterpart. Franz diffusion cells were used to simulate the real environment, and skin isolated from pig ears was used as a membrane. Using UV-VIS spectrophotometry and HPLC, the samples were analyzed. Several values were calculated from the measured data, such as the effective diffusion coefficient, which were then compared and statistically checked. The result of this thesis is data that show the positive effect of humic substances on the transport of drugs through the skin membrane.
Phytoextraction of mixed drug samples from aqueous solutions
Hájková, Eliška ; Smrček, Stanislav (advisor) ; Soudek, Petr (referee)
A number of contaminants have been detected in the environment, including pharmaceuticals. Their presence in soil, water sources can have a toxic effect on organisms due to their constantly increasing concentration. The method of phytoremediation uses the ability of plants to absorb these contaminants and detoxify them by various mechanisms. The aim of this work was the phytoextraction of ibuprofen using maize (Zea mays) from aqueous solutions. Phytoextraction of ibuprofen after cultivation with added dextromethorphan was also carried out. The quantitative amount of extracted ibuprofen was detected by HPLC with UV detection. Ibuprofen has been very well extracted by plants. In the presence of dextromethorphan, the efficiency of phytoextraction was decreased. The phytoextraction efficiency of ibuprofen was 0.10 mg per gram of leaf fresh weight, while in the presence of dextromethorphan, the phytoextraction efficiency was 0.09 mg per gram of leaf fresh weight. After phytoextraction of ibuprofen, the antioxidant capacity was determined by FRAP method of leaf and root extracts of the plants, of which the highest values were observed in the roots of plant grown with ibuprofen in combination with dextromethorphan. The phenolic compounds were also detected in leaves and roots, where the highest percentage...
Electrochemical oxidation of ibuprofen
Bolíková, Markéta ; Křížek, Tomáš (advisor) ; Kozlík, Petr (referee)
- 4 - Abstract This diploma thesis deals with the electrochemical oxidation of the active pharmaceutical ingredient ibuprofen as one of the parts of the stability studies of pharmaceutical products. The task is to ensure optimal conditions for the course of electrochemical oxidation, which produces the largest percentage of degradation products, to compare the flow and static experimental setup and its effect on the result of electrochemical oxidation and to identify the resulting degradation products. The examined conditions include the pH of the buffer used to dissolve ibuprofen, the potential applied to the working electrode and the duration of oxidation. Ultra-high performance liquid chromatography coupled with mass detection was used to separate and determine degradation products. Acquity UPLC BEH C18 (2.1 × 100 mm; 1.7 µm) was chosen as the separation column. The mobile phase consisted of an aqueous component (10mM ammonium formate with pH 3.0) and an organic component (acetonitrile). Detection was performed using a photodiode array detector at a wavelength of 222 nm and a quadrupole mass detector in the scan range m/z 50-400. The electrochemical oxidation was performed in a radial electrochemical flow cell and the conditions under which the largest percentage of degradation products formed were as...
Preparation of nanoparticles and nanofibers with antimicrobial components
Kubišová, Veronika ; Slaninová, Eva (referee) ; Skoumalová, Petra (advisor)
This thesis addresses the problem of inadequate current wound therapy and presents a solution in the form of nanomaterial-based wound dressings (coverings). Specifically, it focuses on the development and characterization of various nanofibrous materials with integrated liposome particles that could serve as a source of therapeutic agents and be useful specifically in the field of a wound therapy. The review in the introductory part of the thesis first focused on the mentioned problem, which describes the shortcomings of existing conventional dressing materials. A description of human skin from an anatomical and functional point of view was not omitted, nor was the wound healing process itself. Different types of covering materials were also presented. However, a large part was focused on nanomaterials and their use in the field of the skin wound therapy. The nanomaterials mentioned were mainly liposome particles and nanofibres, as the experimental part of the work was focused on these structures. The description dealt with the characterization of these structures as well as the biopolymers used for their preparation. However, the aim was to prepare nanofibers with liposome content, so the method of forming such systems was described. Various therapeutic agents are also an integral part of the covering materials, especially those that suppress the development of infection and reduce wound pain; therefore, the search focused on the antibiotic ampicillin and the analgesic ibuprofen. The experimental part was devoted to the actual production of nanofibers with liposomes and also to the qualitative demonstration of the presence of liposomes in electrostatically prepared nanofibers. The selected polymeric components of these systems were polyhydroxybutyrate (PHB) and gelatine. However, the nanofibers and liposome particles (as well as combined liposomes with PHB) were first prepared in their own form and characterized mainly in terms of the gradual release of the drug substances. The results obtained were then compared with those of therapeutic drug delivery via combined nanofibrous structures with liposomes. For these combined structures, the aim was to achieve synergy in drug delivery between these systems. The aim of this work was to create a biomaterial covering with the controlled drug release. The drugs contained in these materials were the aforementioned ampicillin and ibuprofen. An important part of the work was then to determine the safety of the prepared materials which were tested for cytotoxicity, where the tests performed were MTT test and LDH test. And the actual wound healing ability of the nanofibers was then monitored in a scratch test or a "wound healing" test. At the end of the paper, recommendations for future work on this topic are given.
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.
Study of plant stress responces in presence of pharmaceuticals in cultivation medium
Bystroňová, Jana ; Soudek, Petr (advisor) ; Podlipná, Radka (referee)
The aim of this study was to verify the possibility of ibuprofen degradation by selected plant cultures and determination of activities of antioxidant enzymes (peroxidase, catalase, ascorbate peroxidase and glutathione-S-transferase) as markers of oxidative stress caused by ibuprofen. Nicotiana tabaccum (cv. La Burley 21, cv. SR 1 and their GMOs) and Nicotiana glauca were used as experimental plants. The rate of removal of ibuprofen tested by tobacco was decreasing in the following order: N. tabaccum SR1 > N. tabaccum Zm-P60-1-T4 > N. tabaccum TRI 2T2 > N. glauca > N. tabaccum TRI 2T1 > N. tabaccum cv. La Burley > N. tabaccum Zm-P60-1-T5. As the most suitable tobacco for the removal of ibuprofen seemed untransformed N. tabaccum SR1. The long-term experiment showed that plant stress is being manifested even after longtime. N. tabaccum cv. La Burley 21 seemed to be the most tolerant to ibuprofen in compare with the total enzyme activities in cultures with the presence of ibuprofen and controls. N.glauca was the least tolerant cultivar. Keywords: phytoremediation, ibuprofen, Nicotiana tabaccum, Nicotiana glauca, HPLC, peroxidase, catalase, ascorbate peroxidase, glutathion-S-transferase
Interaction of Ibuprofen with Humic Substances and Stability of Formed Complexes
Vlašicová, Silvie ; Smilek, Jiří (referee) ; Klučáková, Martina (advisor)
Nowadays, huge amounts of drugs get into watercourses and soil due to wrong disposal in sewage treatment plants. In this work, the sorption and desorption behavior of Ibuprofen in the soil system was studied, especially in relation to humic acids. The degree of sorption and desorption was defined from the change in ibuprofen concentration analyzed by UV-VIS spectrometry, changes in conductivity and pH were also observed. Ibuprofen shows good sorption properties, desorption was really minimal. It can be assumed that there is a strong bond between ibuprofen and both soil and lignite humic acids and therefore there is no risk of leaching back into solutions. Therefore, if ibuprofen entered the environment, it would be sorbed into the humic acids contained in lignite or soil, which means that it should not be harmful in any way.
Preparation and characterization of modern wound covers
Balášová, Patricie ; Pernicová, Iva (referee) ; Skoumalová, Petra (advisor)
This diploma thesis is focused on the study of bioactive wound dressings. During the thesis, hydrogel, lyophilized and nanofiber wound dressings were prepared. Hydrogel and lyophilized wound dressings were prepared on basis of two polysaccharides – alginate and chitosan. Nanofiber wound dressings were prepared by spinning polyhydroxybutyrate. All prepared wound dressings were enriched with bioactive substances, which represented analgesics (ibuprofen), antibiotics (ampicillin) and enzymes (collagenase). Into hydrogel and lyophilized wound dressings were all the mentioned active substances incorporated, whereas nanofiber wound dressings were only with ibuprofen and ampicillin prepared. The theoretical part deals with the anatomy and function of human skin. There was explained the process of wound healing and also there were introduced available modern wound dressings. The next chapter of the theoretical part deals with materials for preparing wound dressings (alginate, chitosan, polyhydroxybutyrate) and with active substances, which were used during the experimental part of this thesis. In the theoretical part, the methods of preparation of nanofiber wound dressings and also the methods of cytotoxicity testing used in this work were presented. The first part of the experimental part of this thesis was focused on preparing already mentioned wound dressings. Then, their morphological changes over time and also the gradual release of incorporated active substances into the model environment were monitored. The gradual release of ampicillin was monitored not only spectrophotometrically, but also by ultra-high-performance chromatography. In wound dressings, in which collagenase was incorporated, was also the final proteolytic activity of this enzyme monitored. The effect of the active substances was observed on three selected microorganisms: Escherichia coli, Staphylococcus epidermidis and Candida glabrata. The cytotoxic effect of the active substances on the human keratinocyte cell line was monitored by MTT test and LDH test. A test for monitoring the rate of wound healing – a scratch test – was also performed.

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