Institute of Analytical Chemistry

Latest additions:
2019-04-29
09:26
Polycyklické aromatické uhlovodíky v PM1 aerosolu na 6 lokalitách v České republice
Křůmal, Kamil ; Mikuška, Pavel
PAHs byly měřeny v zimní sezóně ve městech Ostrava-Radvanice (průmyslová lokalita), Brno, Mladá Boleslav, Kladno-Švermov, Čelákovice, Košetice (pozaďová lokalita). Z koncentrací PAHs v PM1 aerosolu byly počítány rizika vzniku rakoviny plic.

Detailed record
2019-04-29
09:26
Stanovení rychlých změn koncentrací těkavých organických sloučenin pomocí difúzního denuderu
Křůmal, Kamil ; Mikuška, Pavel
Stanovení rychlých změn koncentrací těkavých organických sloučenin bylo provedeno využitím difúzního denuderu se stékajícím filmem kapaliny, který umožňuje odběr vzorků v časových intervalech již od 2 minut.

Detailed record
2019-01-07
14:42
Epitachophoretic separation and concentration of large volume samples
Voráčová, Ivona ; Foret, František ; Datinská, Vladimíra ; Novotný, Jakub ; Gheibi, P. ; Berka, J. ; Astier, Y.
There has been a growing interest in developing isotachophoretic protocols for concentration and purification of DNA as an alternative to the solid phase extraction protocols of DNA preparation. Also concentration of DNA from large volume samples is required. We have developed a new device suitable for separation, concentration and collection of ions from several milliliter sample volumes into microliter fractions. We have used a discontinuous electrolyte system comprising of the leading and terminating electrolytes utilized for concentration of samples containing DNA fragments. The method is simple, fast with high concentration factor and without extensive surface interactions.

Detailed record
2019-01-07
14:42
Surface enhanced raman spectroscopy: Detection platforms for sample analysis with and without electrophoretic separation
Týčová, Anna ; Přikryl, Jan ; Foret, František ; Belder, D.
In this work we present two platforms of relatively simple construction for user-friendly sample detection via surface enhanced Raman spectroscopy (SERS). The first platform is designed for direct sample analysis and deals with hydrophilic spots array within a hydrophobic surface. The second presented platform aims on analysis of samples of higher complexity requiring separation step prior the detection. This is achived via microfluidic electrophoretic device with online SERS detection.

Detailed record
2019-01-07
14:42
A New evaluation of combined antitumor effects of natural and synthetic nuclear retinoid receptor ligands in human breast carcinoma cells
Strouhalová, Dana ; Laštovičková, Markéta ; Bobál, P. ; Macejová, D. ; Mosná, B. ; Brtko, J. ; Bobálová, Janette
This work represents the study of the effects of biologically active ligands of nuclear retinoid X receptors, triorganotin compounds, on proteomic profile of MDA-MB-231 cells. We focused primarily on tributyl/phenyltin derivatives that suggest the combined antitumor effect when they are used with natural nuclear retinoid receptor ligand all-trans retinoic acid (ATRA). Proteomic strategies connected to PDQuest evaluation were applied in this study. Some specific proteins with tumor process association were chosen for more detail study. Our findings indicate that selected triorganotins derivatives resulted to significantly reduced level of studied proteins belonging to metabolic pathway or to other cellular processes as apoptosis or epithelial–mesenchymal transition. In the case of vimentin, the key protein of EMT process, the silencing was set up by triorganotin compounds and significantly enhanced by combination with ATRA. This additive effect on downregulation can result from the potential engagement of RXR/RAR heterodimer, considering co-addition of both partner ligands of mentioned heterodimer to the treatment.

Detailed record
2019-01-07
14:42
Maximizing efficiency of field-amplified electrokinetic injection of weak bases for enantioselective capillary electrophoresis with sulfated cyclodextins
Šesták, Jozef ; Thormann, W.
The optimal conditions for field-amplified electrokinetic injection of cations followed by their separation based on the stereoselective interaction with sulfated cyclodextrins are discussed. Results show that addition of a short water plug together with a short plug free of cyclodextrins and with a buffer concentration similar to the BGE greatly increase the injection efficiency.

Detailed record
2019-01-07
14:42
Determination of permeability of ulra-fine lead oxide aerosols through military filters
Kellnerova, E. ; Večeřa, Zbyněk ; Kellner, J. ; Zeman, T. ; Hylak, Č.
Military filters introduced in the Army of the Czech Republic are most commonly used when working with combat equipment and weapons and in manoeuvring activities in the terrain with the use of explosives or chemical warfare agents. During such activities, a large number of pollutants in the form of nanoparticles are released. Nanoparticles, irrespective of their chemical composition, are classified as carcinogenic to humans and therefore it is necessary to eliminate them from the air. Military filters, especially the combined ones, which contain a filtration as well as sorption component, are most widely used and are designed for the widest range of pollutants. However, the current methodology to evaluate the effectiveness of military filters does not fix a duty to monitor the ability of the filters to capture relevant pollutants across the whole range of sizes. The paper evaluates the efficiency of selected types of military filters using the methodology and instrumentation introduced in the accredited laboratories of the Institute of Analytical Chemistry of the Academy of Sciences of the Czech Republic. The testing has been carried out simultaneously with two concentrations of ultra-fine aerosols containing lead oxide nanoparticles ranging in size from 7.6 nm to 299.6 nm. It is an aerosol, the physicochemical and toxicological properties of which are known. During the work the basic parameters of permeability of aerosols tested by filters have been evaluated, especially: size and number of particles in front of and behind the filter, the efficiency and penetration of nanoparticles by the filter.

Detailed record
2019-01-07
14:42
Rapid fabrication of microextraction devices for direct determination of basic drugs in dried blood spots
Ryšavá, Lenka ; Přikryl, Jan ; Dvořák, Miloš ; Malá, Zdeňka ; Kubáň, Pavel
A 3D-printed cutter was designed for rapid fabrication of supported liquid membrane (SLM) extraction devices compatible with injection system of commercial capillary electrophoresis (CE) instrument. Low cost and single use microextraction devices were fabricated from polypropylene micropipette tips with high precision (dimension variances ≤ 3% RSD). Practical applicability of the microextraction devices was examined by in-line coupling of SLM extractions to CE for direct analysis of four model basic drugs in dried blood spot extracts. Excellent repeatability of the hyphenated technique was achieved (RSD ≤ 7.6%), transfer of analytes across the SLM ranged from 23 to 73% and limits of detection were as low as 0.07 μg/mL.

Detailed record
2019-01-07
14:42
Arduino-based pressure-driven flow controller for droplet microfluidics
Přikryl, Jan ; Křivánková, Jana ; Hlaváček, Antonín
Droplet-based microfluidic systems bear significant value in an extremely wide range of applications due to its remarkable advantages, nevertheless, their technical demands on precise flow control are high. Here, we present lab-built Arduino-based flow controller fulfilling needs of droplet microfluidics to easily and effectively automate the system. As an additional required accessory, CNC-milled component for vials pressurizing was presented.

Detailed record
2019-01-07
14:42
Hexahistidine-based tag for capillary electrophoresis-mass spektrometry analysis of oligosaccharides and N-linked glycans
Partyka, Jan ; Křenková, Jana ; Čmelík, Richard ; Foret, František
Various basic amino acids and peptides were studied as an alternative labels for capillary electrophoresis-mass spectrometry analysis of oligosaccharides. The hexahistidine-based label with big number of positive charges allowed to use effective and sensitive CE-MS analysis in positive ion mode both neutral and acidic glycans.

Detailed record