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Transport systems used in cosmetics
Škopová, Jitka ; Kramářová,, Daniela (referee) ; Zemanová, Jana (advisor)
Between transport systems in cosmetics belong liposomes, liquid crystals and also chosen substances, which speed under given conditions a transport of active compounds, so-called accelerators of trans-dermal penetration. Liposomes are used topically (i.e. directly onto the place of their action in surface structures of organism) in dermatological and cosmetic preparations, they facilitate the penetration of active substances into the deeper layers of the skin and make possible their more expressive treatment. Some properties of liquid crystals are similar to the properties of live organisms. Analogous to the vital cells are they sensitive to light, sound, warm, mechanical straining and chemical changes. And by contraries, some scientists mark vital cells as liquid crystals. Thanks to this similarity are liquid crystals characterized by their excellent ability to penetrate by the skin, which is probably comparable only with liposomes. Accelerators of trans-dermal penetration otherwise accelerators of penetration by the skin are substances, which change structure of the skin or derma to be more permeable for other compounds. The trans-dermal penetration of active substances is an important part of medical researches. Those results are however applied also in other branches as for example is cosmetic industry. From the point of view of the chemical texture of these materials form they a very heterogeneous group and an elucidating of mechanisms of their incidence is so far rather in beginnings.
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Optimalization of experimental method for study on penetration of humic acids into leaves.
Smilková, Marcela ; Pekař, Miloslav (referee) ; Sedláček, Petr (advisor)
This bachelor’s thesis is focused on the study of penetration of humic substances trough the plant cuticle. The main objective of the thesis aimed at a literature search on foliar fertilization and transport of substances in the plant leaves. According to the literature search, experimental technique was suggested and tested in order to study penetration of humic substances through the leaf cuticle. The method consists of observation of diffusion transport of humic acids between two inert agarose gels separated by the plant cuticle. Cuticles were prepared by the means of three different isolation procedures.
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The synthesis and development of new catalyst with the bipyridine scaffold.
Kadlčíková, Aneta ; Kotora, Martin (advisor) ; Starý, Ivo (referee) ; Veselý, Jan (referee)
1 Abstract Chiral N,N'-dioxides serve as very useful catalysts in various enantioselective reactions. I developed a simple and efficient method for preparation of new unsymmetrically substituted axially chiral bis(tetrahydroisoquinolines)-N,N'-dioxides, based on "one-pot" [2+2+2]-cyclotrimerization of a tetrayne with benzonitrile and (R)-tetrahydrofurancarbonitrile catalyzed by CpCo(CO)2 under microwave irradiation (scheme 1)1,2 . First, the prepared chiral N,N'-dioxides were used as catalysts in highly enantioselective allylations of variously substituted aromatic, aliphatic and α,β-unsaturated aldehydes. The corresponding homoallylalcohols were obtained with ee up to 99%. Two obtained chiral homoallylalcohols prepared by allylation were used as a building-blocks for synthesis of some natural products such as (S)-(-)-Goniothalamin (scheme 2)3 . Second, the chiral N,N'-dioxides were also used for the epoxide ring opening of various meso-epoxides with tetrachlorosilane giving rise to chlorohydrines in moderate enantioselectivities (up to 64% ee) (scheme 3)4 . N N OScheme 1 + N N O O O CpCo(CO)2 MCPBA O NC NC SiCl3 Cat. (1-5mol%) O O (S)-(-)-Goniothalamin, 97% ee Ph R OH up to 99% ee Scheme 2 R R R = phenyl, alkyl O OHClSiCl4 up to 64% ee R H O R= Ar, alkyl, ArCH=CH, alkyl-CH=CH Ph H Scheme 3 Cat. O Cat....
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Aggregation processes in amphiphil-polymer system
Šejnohová, Michaela ; Márová, Ivana (referee) ; Pekař, Miloslav (advisor)
This Bachelor´s thesis is focused on the exploration of polyelectrolyte-surfactant system by fluorescence spectroscopy with pyrene as fluorescent probe. Cationic cetyltrimethylammonium bromide (CTAB) was used as a surfactant. Native hyaluronan was used as polyelectrolyte. Hyaluronan was used in one constant molecular weight and one constant concentration. The whole system was prepared in an aqueous environment. Interactions were studied in area between critical aggregation concentration (CAC) and critical micelle concentration (CMC). The influences of the concentration of pyrene and the effect of the way of the samples preparation on aggregation behavior were also studied. It was found that above the critical aggregation concentration exists an area where stable properties of aggregates can be found. The concentration of pyrene has a major effect on the fluorescence properties of the system. Preparation of samples affects the aggregation of the system. At higher surfactant concentrations, above the stable area, was observed phase separation and gel formation.
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