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Hyaluronan ionocomplexes for cosmetic and farmaceutical applications
Cimalová, Jana ; Obruča, Stanislav (referee) ; Pekař, Miloslav (advisor)
This bachelor thesis is focused on the study of a system of cationic surfactant – hyaluronan. Using fluorescent spectroscopy the critical micellar concentration of Carbethopendecinium bromide (Septonex) was determined in three environments – water, 0,15 M NaCl, and buffer PBS, with three fluorescent probes – pyrene, perylene, and nile red. It was found that the physiological environments (buffer and NaCl) reduce the value of CMC about one order. During the experiments with native hyaluronan, precipitate and gel formation were observed. The following part dealt with aggregate behaviour of the new biologically acceptable amphoteric surfactant tetradecylfosfocholine (TPC) in the environment of water and NaCl according to the increasing molar molecular weight of hyaluronan. As a fluorescent probe perylene was used. These measurements showed that the molar molecular weight or a change of ionic force has no effect on the value of CMC and therefore there are no interactions with hyaluronan. The last surfactant to study was 1,2-dihexadecanoyl-3-dimetylammonium-propan (DPTAP), which is water insoluble. DPTAP is soluble in chloroform, but after evaporation of chloroform and after addition of hyaluronan, it precipitated. The results so far, have confirmed that in terms of research of aggregation by fluorescence spectroscopy the new cationic surfactants TPC and DPTAP are not suitable for complexation with hyaluronan.
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Interaction between amphiphilic fluorescent probes and hyaluronan
Střondalová, Hana ; Vala, Martin (referee) ; Mravec, Filip (advisor)
This bachelor thesis dealt with studying the interaction of amphiphilic fluorescent probes with hyaluronan because these probes could significantly help in clarifying the links between hyaluronan and surfactants. This complex could be a great benefit in targeting drug distribution. This thesis was focused on the interaction between hyaluronan and amphiphilic fluorescent probes – specifically with dodecylacridine orange. First explored was the interaction with hyaluronan, and then with the hyaluronan – surfactant system. Cetyltrimethylamonium bromide was selected as surfactant. Samples were examined using fluorescence spectroscopy. Emission and absorption spectrum of dodecyl acridine orange was measured. This experiment was based on the hypothesis that dodecylacridine orange forms dimers as acridine orange and nonylacridine orange. It was found that in a system of hyaluronan-probe, dodecyl acridine orange was pushed out of the complex by cetyltrimethylamonium bromide, which was bounded instead. Surfactant interacts with hyaluronan binding positions - with carboxyl groups.
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Interaction in ionic surfactant/non-ionic surfactant/polyelectrolyte system
Pihíková, Dominika ; Sedláček, Petr (referee) ; Mravec, Filip (advisor)
The interactions in an ionic surfactant/non-ionic surfactant/polyelectrolyte system have been studied in this bachelor thesis. The value of critical micelle concentration of cationic didecyldimethylammonium chloride (DDAC) has been determined in three different mediums by fluorescence spectroscopy using Pyrene, Perylene and Nile red as probes. The CMC value of non-ionic octylphenol ethoxylate (Triton X-100) has been determined using Pyrene and Perylene as probes. The aggregation behavior of non-ionic and ionic surfactant with addition of polyelectrolyte poly(sodium4-styrensulfonate) (PSS) and native hyaluronan in aqueous solution has been investigated using Pyrene as a probe. Aggregation number in system of ionic/non-ionic surfactant has been determined by a fluorescence quenching with cetylpyridium (CPC) as a quencher and Pyrene as a fluorescence probe. Interactions in ionic surfactant/non-ionic surfactant/polyelectrolyte system were observed. This result was proved by double sigmoid Boltzman´s type curve. The addition of low molecular as well as high molecular hyaluronan had no significant effect on CMC value of the system.
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Study of aggregation in a biopolymer-surfactant system at low surfactant concentration.
Stiborský, Filip ; Vojtová, Lucy (referee) ; Mravec, Filip (advisor)
In this bachelor thesis, the interaction between hyaluronate and surfactant using fluorescent spectroscopy and pyrene as fluorescent probe was studied. A cationic surfactant cetyltrimethylammonium bromide and a native hyaluronate with different molecular size was used. Before a detected critical micelle concentracion, there were no interactions observed in phosphate buffer. However, we could observe electrostatical interactions in the water systém measuring. At low concentration of surfactant (between critical aggregation concentration and critical micelle concentration), the production of gel phase appeared.
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Cationic fluorescence probes in a polyanion-surfactant system.
Mondek, Jakub ; Šmejkalová, Daniela (referee) ; Pekař, Miloslav (advisor)
In this bachelor thesis were studied properties of aqueous solutions of hyaluronan and celytrimethylamonnium bromid with help of acridine orange as fluorescence probe. At first, this thesis was focused on interactions of acridine orange and hyaluronan. Emision and excitation spectra of acridine orange were observed. Result of these measurement was bonding of acridine orange dimer to carboxylic group of hyaluronan. Next studied interaction was interaction of cetyltrimethyl amonium bromid with acridine orange – hyaluronan system. Result of these interaction was, that molecules of cationactive surfactant pushed away dimers of acridine orange and took place of dimer of acridine orange on carboxylic group of hyaluronan. Dimer of acridine orange was changed into monomers. The reason why this thesis was focused on study of aqueus solutions of hyaluronan with cationactive surfactant is benefit of hyaluronan – surfactant system in research of transport system for target distribution of drugs.
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Influence of the temperature on hydrophobic domain quality in a biopolymer-surfactant system.
Hnyluchová, Zuzana ; Kopuletá, Ema (referee) ; Mravec, Filip (advisor)
The temperature dependence on polarity has been investigated by fluorescence spectroscopy with pyrene as a probe. Pyrene was chosen thanks to its unique sensitivity to polarity of the medium. As a biopolymer was chosen 73 kDa and 1,4 MDa hyaluronic acid. Emission spectra of pyrene were measured as a function of temperature in aqous solution of CTAB in a presence and absence of sodium chloride. The results show, that the addition of specific concentration of hyaluronic acid to the sample with CTAB, mostly doesn´t have effect to change increasing/decreasing slope of polarity with the temperature.
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Assessmant of surfactants levels in waters
Zajícová, Markéta ; Doležalová Weissmannová, Helena (referee) ; Vávrová, Milada (advisor)
The present Bachelor Thesis deals with problem of water contamination by synthetic surfactants. Surfactants represent the main component of washing and cleaning agents, from which they enter waste waters. The goal of Thesis was to monitor and evaluate volume of surfactants in waste waters from waste water treatment plant VFU Brno. Samples were being taken in the course of 7 days and we have monitored volume of anionic and cationic tensides in samples from influent and effluent stream of waste water treatment plant. For qualitative and quantitative determination were used mobile analytic measurement devices with photometric detection by company Merck. Results were processed and interpreted in data evaluation section in the end of this Bachelor Thesis.
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Evaluation of methods for determination of surfactants
Soukupová, Alena ; Doležalová Weissmannová, Helena (referee) ; Vávrová, Milada (advisor)
This bachelor thesis deals with the evaluation of the methods used for the determination of surfactants. On the base of literature search the review of possible methods applicable for the determination of detergents in the surface waters and wastewaters was set up. The theoretical part presents the definitions of the surface water and wastewater, possible sources of pollution are discussed and methods of water cleaning are listed. The definition and classification of various classes of surfactants is also included. This work is theoretical; therefore the evaluation was made on the basis of the information obtained from accessible literature. The evaluation of the discussed methods is given in the conclusion.
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