|
|
Studium transportu iontů přes modelové fosfolipidové membrány
Navrátil, Tomáš ; Šestáková, Ivana ; Mareček, Vladimír
Synthetically prepared model phospholipid bilayers (PLBs) in the form of black membranes, vesicles or supported membranes, with incorporated ionophores or real ion channels (i.e., artificially synthesized or gained from real living cells, e.g. protoplasts) are promising for study and simulations of transporting processes across the real cell membranes and the membranes surrounding sub-cellular structures. The electrochemical methods were found to be very suitable and sensitive enough for characterization of such processes.
|
|
| |
|
|
Přenos kadmia přes biologické membrány
Šestáková, Ivana ; Navrátil, Tomáš
From complexing ligands, low molecular weight organic acids are important as plant exudates in soil solution, whereas sulfur containing - ligands phytochelatins - sequester Cd2+ inside the cell vacuole. Voltammetrically determined fytochelatins concentration could be correlated with total Cd concentration found in different parts of plant.
|
|
| |
|
|
Význam lipidů v metabolismu tuků
Kohlíková, E. ; Petr, M. ; Přistoupilová, K. ; Přistoupil, T. I. ; Pelclová, D. ; Žák, J. ; Heyrovský, Michael ; Navrátil, Tomáš
In course of last two years we compared values of 34 parameters, obtained from 11 young active sportsmen given 5 g of creatine (CR) daily during 1 month. Among these parameters were the products of metabolic pathways, the changes of which are connected with the development of atherosclerosis. This holds for the levels of cholesterol (CH), triacylglycerols (TAG) and homocysteine (HoCySH), and for the levels of vitamin B12 and of folates in blood.
|
|
|
Preparation and Properties of Mercury Films on Solid Amalgam Surface
Josypčuk, Bohdan
There have been suggested a simple electrolyzer and a reliable procedure for preparation of mercury films with precisely defined thickness on a conducting surface. A small volume of electrolyte which can be used more times and a paste amalgam which cannot spill substantially decrease a risk of environment contamination. Measurements were parallelly performed on a liquid mercury free silver solid amalgam electrode (AgSAE), on a mercury meniscus modified AgSAE and on HMDE for comparing their properties with those of the mercury film electrodes (MF-AgSAE). A current response of the film electrodes is the biggest. The peak width, which determines the method resolution, is smallest on the film electrodes. Range of working potentials on MF-AgSAE is comparable with one on HMDE in different supporting electrolytes.
|
|
| |
|
| |
|
|
Patch Clamp Technique – The Tool for Ions Transport across Model and Real Biological Membranes
Navrátil, Tomáš ; Jaklová Dytrtová, J. ; Jakl, M. ; Šestáková, Ivana ; Mareček, Vladimír ; Krůšek, Jan
The project is aimed at the preparation and characterization of model and/or real phospholipid bilayers at stabilized phase boundaries enabling studies of transfer of charged and uncharged species between the two phases. The best way for investigation of inorganic ion transfer is provided by using mercury as one of the phases, in view of the large amount of the relevant electrochemical data available, whereas the transfer of more complex species is better studied in the system of an organic and an aqueous phase stabilized by (agar) gel. The results contribute to the understanding of ion transport across real membranes. Polypeptides and peptides capable forming ionic channels and enabling transport of various ions and molecules across the membranes, will be incorporated into the model membranes. The possibilities of transport of selected compounds across the model membrane will be investigated using cell permeable peptides as well.
|
|
|
Electrochemical detection of trace amounts of nitrated explosives
Barek, J. ; Fischer, J. ; Vyskočil, V. ; Pecková, K. ; Navrátil, Tomáš ; Josypčuk, Bohdan
Nitrated organic compounds belong to the group of the most frequently used explosives. Detection of low levels of such compounds is very attractive in these days. Due to the easy reducibility of the nitro group, voltammetry seems to be very suitable method for these purposes. For these determinations the following electrodes were used: were used hanging mercury drop electrode, meniscus modified silver solid amalgam electrode, miniaturized paste silver amalgam electrode, paste electrode on the basis of silver amalgam powder and proper organic liquid were used.
|
guest ::
