Email: petr.frycak@upol.cz
Location: 17. listopadu 12, Olomouc
Phone: (+420) 585634413
Fax: (+420) 585 634 433
Oblast výzkumu:
???????????????????????????????
Kvalifikace:
Mgr.: ????????????????????????????????
Ph.D.: ??????????????????????????????????
Publications
2011
-
K. A. Schug, C. Serrano, and P. Frycak, “CONTROLLED BAND DISPERSION FOR QUANTITATIVE BINDING DETERMINATION AND
ANALYSIS WITH ELECTROSPRAY IONIZATION-MASS SPECTROMETRY (vol 29, pg 806,
2010),” MASS SPECTROMETRY REVIEWS, vol. 30, iss. 1, pp. 176, 2011.
[Bibtex]@article ISI:000285427300005, Author = Schug, Kevin A. and Serrano, Carlos and Frycak, Petr, Title = CONTROLLED BAND DISPERSION FOR QUANTITATIVE BINDING DETERMINATION AND ANALYSIS WITH ELECTROSPRAY IONIZATION-MASS SPECTROMETRY (vol 29, pg 806, 2010), Journal = MASS SPECTROMETRY REVIEWS, Year = 2011, Volume = 30, Number = 1, Pages = 176, Month = JAN-FEB, DOI = 10.1002/mas.20327, ISSN = 0277-7037, Unique-ID = ISI:000285427300005,
2010
-
K. A. Schug, C. Serrano, and P. Frycak, “CONTROLLED BAND DISPERSION FOR QUANTITATIVE BINDING DETERMINATION AND
ANALYSIS WITH ELECTROSPRAY IONIZATION-MASS SPECTROMETRY,” MASS SPECTROMETRY REVIEWS, vol. 29, iss. 5, pp. 806-829, 2010.
[Bibtex]@article ISI:000281724300006, Author = Schug, Kevin A. and Serrano, Carlos and Frycak, Petr, Title = CONTROLLED BAND DISPERSION FOR QUANTITATIVE BINDING DETERMINATION AND ANALYSIS WITH ELECTROSPRAY IONIZATION-MASS SPECTROMETRY, Journal = MASS SPECTROMETRY REVIEWS, Year = 2010, Volume = 29, Number = 5, Pages = 806-829, Month = SEP-OCT, Abstract = This review discusses recent emerging techniques that have been used to couple flow-injection analysis (FIA) and electrospray ionization-mass spectrometry (ESI-MS) for the quantitation of noncovalent binding interactions. Focus is placed predominantly on two such methods. Diffusion-based measurements, developed by Konermann and co-workers, uses controlled-band dispersion prior to ESI-MS to determine diffusion constants and binding constants based on the temporal variation of ligand signal measured in the mass spectrum (an indirect technique). Dynamic titration, developed by Schug and co-workers, is a direct method, where a temporal compositional gradient of a guest molecule is induced in the presence of host in solution to monitor the concentration dependence of complex formation as a function of observed complex ion abundance after ESI-MS. Further discussion places these techniques in the context of a variety of other direct and indirect ESI-MS-based binding determination methods, and highlights advantages, disadvantages, and practical considerations for their proper use to investigate a broad range of macromolecular and small-molecule interaction systems. (C) 2009 Wiley Periodicals, Inc., Mass Spec Rev 29:806-829, 2010, DOI = 10.1002/mas.20267, ISSN = 0277-7037, Unique-ID = ISI:000281724300006,
2006
-
B. Papouskova, P. Bednar, P. Bartak, P. Frycak, J. Sevcik, Z. Stransky, and K. Lemr, “Utilisation of separation methods in the analysis of chemical warfare
agents,” JOURNAL OF SEPARATION SCIENCE, vol. 29, iss. 11, pp. 1531-1538, 2006.
[Bibtex]@article ISI:000239574100001, Author = Papouskova, Barbora and Bednar, Petr and Bartak, Petr and Frycak, Petr and Sevcik, Juraj and Stransky, Zdenek and Lemr, Karel, Title = Utilisation of separation methods in the analysis of chemical warfare agents, Journal = JOURNAL OF SEPARATION SCIENCE, Year = 2006, Volume = 29, Number = 11, Pages = 1531-1538, Month = JUL, Abstract = Chemical warfare agents and their degradation products represent a broad group of compounds with different chemical properties (polarity, volatility, thermostability, etc.). These chemicals often have to be detected and determined in complex matrices and therefore highly efficient separation techniques hyphenated to selective and sensitive detectors play an indispensable role. This review offers an overview of selected papers devoted to the title subject. It cannot be considered as a comprehensive literature compilation but should allow the reader to obtain an insight into the application of separation techniques in the important area of human protection and control of chemical weapons., DOI = 10.1002/jssc.200500432, ISSN = 1615-9306, Unique-ID = ISI:000239574100001, -
K. Lemr, V. Ranc, P. Frycak, P. Bednar, and J. Sevcik, “Chiral analysis by mass spectrometry using the kinetic method in flow
systems,” JOURNAL OF MASS SPECTROMETRY, vol. 41, iss. 4, pp. 499-506, 2006.
[Bibtex]@article ISI:000237364700008, Author = Lemr, K and Ranc, V and Frycak, P and Bednar, P and Sevcik, J, Title = Chiral analysis by mass spectrometry using the kinetic method in flow systems, Journal = JOURNAL OF MASS SPECTROMETRY, Year = 2006, Volume = 41, Number = 4, Pages = 499-506, Month = APR, Abstract = Chiral analysis is an important task of analytical chemistry. Besides separation techniques, mass spectrometry can be applied in this field. One mass spectrometric approach is based on Cooks' kinetic method. The method was successfully applied in a static system in which the concentration of the analyte as well as the chiral selector solution was constant during the experiment. The application of the kinetic method in dynamic systems (changing concentration of analyte) is presented. Such systems allow the speeding up of the analytical process (flow injection analysis (FIA)) or the use of the kinetic method for chiral detection after liquid chromatographic separation. The influence of the concentration of the components of the chiral selector solution as well as its flow rate on the recognition of enantiomers was evaluated. A new procedure for correction for the differences between ratio of enantiomers in the liquid phase and their observed ratio in the gas phase is also described. A significant improvement in accuracy using this procedure was achieved. Applicability of the method was demonstrated in the analysis of amino acids using FIA as well as HPLC/MS. After an achiral separation of leucine and isoleucine, chiral mass spectrometric detection was successfully used for enantiomeric recognition. Copyright (c) 2006 John Wiley \& Sons, Ltd., DOI = 10.1002/jms.1008, ISSN = 1076-5174, Unique-ID = ISI:000237364700008, -
P. Vyskocilova, P. Hornik, D. Friedecky, P. Frycak, K. Lemr, and T. Adam, “Synthesis and mass spectrometric fragmentation characteristics of
imidazole ribosides-analogs of intermediates of purine de novo synthetic
pathway,” NUCLEOSIDES NUCLEOTIDES & NUCLEIC ACIDS, vol. 25, iss. 9-11, pp. 1237-1240, 2006.
[Bibtex]@article ISI:000242019000051, Author = Vyskocilova, P. and Hornik, P. and Friedecky, D. and Frycak, P. and Lemr, K. and Adam, T., Title = Synthesis and mass spectrometric fragmentation characteristics of imidazole ribosides-analogs of intermediates of purine de novo synthetic pathway, Journal = NUCLEOSIDES NUCLEOTIDES \& NUCLEIC ACIDS, Year = 2006, Volume = 25, Number = 9-11, Pages = 1237-1240, Note = 10th Symposium of the European-Society-for-the-Study-of-Purine-and-Pyrimidine-Metabolism-in-Ma n (ESSPPMM), Prague, CZECH REPUBLIC, JUN 08-11, 2005, Organization = European Soc Study Purine \& Pyrimidine Metabolism Man, Abstract = Two inherited deficiencies have been described in purine de novo synthesis pathway. Both the defects are diagnosed by detecting ribosides - dephosphorylated substrates of the enzymes - in patient's urine. We describe here a synthesis and mass spectrometric fragmentation of ribosides potentially of diagnostic importance for defects in the second part of the pathway. All the species, except 5-amino-4-imidazolesuccinocarboxamideriboside can be synthesized from the commercially available 5-amino-4-imidazolecarboxamideriboside by chemical methods. Fragmentation spectra of the compounds were obtained by the ion trap mass spectrometry. During fragmentation an opening of the imidazole ring was not observed for any of the compounds but loss of its substituents in the form of small molecules ( NH3, CO2, CO) is the major route of fragmentation. The ribose moiety cleaves off molecule( s) of water, undergoes a cross-ring cleavage or breaks away as a whole., DOI = 10.1080/15257770600894691, ISSN = 1525-7770, Unique-ID = ISI:000242019000051, - V. Ranc, P. Frycak, L. Muller, P. Bednar, and K. Lemr, “Recognition of isomers by mass spectrometry using the kinetic method,” CHEMICKE LISTY, vol. 100, iss. 3, pp. 196-203, 2006.
[Bibtex]@article ISI:000236139700008, Author = Ranc, V and Frycak, P and Muller, L and Bednar, P and Lemr, K, Title = Recognition of isomers by mass spectrometry using the kinetic method, Journal = CHEMICKE LISTY, Year = 2006, Volume = 100, Number = 3, Pages = 196-203, Abstract = The principle of the Cooks'kinetic method and its application to analysis of isomeric mixtures are described. The kinetic method based on mass spectrometric measurements is applied to discrimination of isomers of various types of compounds (amino acids, peptides, sugars, pharmaceuticals, etc.). So far this method has been used in static systems (with constant analyte concentrations in the course of analytical run). A modification for dynamic systems (flow injection analysis, HPLC) is presented. The accuracy of determination in both static and dynamic systems can worsen due to different ratios of the isomers in liquid and gas phases. A procedure for correction of this phenomenon is also demonstrated., ISSN = 0009-2770, Unique-ID = ISI:000236139700008,
2005
-
P. Frycak, Z. Zdrahal, J. Ulrichova, W. Wiegrebe, and K. Lemr, “Evidence of covalent interaction of fumaric acid esters with sulfhydryl
groups in peptides,” JOURNAL OF MASS SPECTROMETRY, vol. 40, iss. 10, pp. 1309-1318, 2005.
[Bibtex]@article ISI:000233019900005, Author = Frycak, P and Zdrahal, Z and Ulrichova, J and Wiegrebe, W and Lemr, K, Title = Evidence of covalent interaction of fumaric acid esters with sulfhydryl groups in peptides, Journal = JOURNAL OF MASS SPECTROMETRY, Year = 2005, Volume = 40, Number = 10, Pages = 1309-1318, Month = OCT, Abstract = Fumaric acid esters, namely dimethylfumarate, have been used for the treatment of psoriasis for many years. Still, their mode of action is not fully clear. Because addition of nucleophiles to the double bonds of fumarates can occur (Michael analogous addition), a study of the interaction of fumarates with cysteine and cysteine-containing peptides possessing nucleophilic sulfhydryl group was carried out. Experiments were performed in aqueous medium at pH 7.4 and at 37 degrees C to simulate physiological conditions. It was proven by mass spectrometric measurements using an ion-trap and time-of-flight instrument that a covalent bond can form between fumarates and the sulfhydryl group of cysteine or cysteinyl residues in peptides. Structures of the interaction products were elucidated by multistage mass spectrometry applying collision-induced dissociation. Higher reactivity of dimethylfumarate in comparison to monomethylfumarate and fumaric acid was observed. Copyright (c) 2005 John Wiley \& Sons, Ltd., DOI = 10.1002/jms.910, ISSN = 1076-5174, Unique-ID = ISI:000233019900005, -
Z. Lamplot, M. Sebela, P. Frycak, S. Longu, A. Padiglia, R. Medda, G. Floris, and P. Pec, “Reactions of plant copper/topaquinone amine oxidases with N-6-aminoalkyl
derivatives of adenine,” JOURNAL OF ENZYME INHIBITION AND MEDICINAL CHEMISTRY, vol. 20, iss. 2, pp. 143-151, 2005.
[Bibtex]@article ISI:000228805000006, Author = Lamplot, Z and Sebela, M and Frycak, P and Longu, S and Padiglia, A and Medda, R and Floris, G and Pec, P, Title = Reactions of plant copper/topaquinone amine oxidases with N-6-aminoalkyl derivatives of adenine, Journal = JOURNAL OF ENZYME INHIBITION AND MEDICINAL CHEMISTRY, Year = 2005, Volume = 20, Number = 2, Pages = 143-151, Month = APR, Abstract = Plant copper/topaquinone-containing amine oxidases (CAOs, EC 1.4.3.6) are enzymes oxidising various amines. Here we report a study on the reactions of CAOs from grass pea ( Lathyrus sativus), lentil ( Lens esculenta) and Euphorbia characias, a Mediterranean shrub, with N-6-aminoalkyl adenines representing combined analogues of cytokinins and polyamines. The following compounds were synthesised: N-6-(3-aminopropyl) adenine, N-6-(4-aminobutyl) adenine, N-6-(4-amino-trans-but-2-enyl) adenine, N-6-(4-amino-cis-but-2-enyl) adenine and N-6-(4-aminobut-2-ynyl) adenine. From these, N-6-(4-aminobutyl) adenine and N-6-(4-amino-trans-but-2-enyl) adenine were found to be substrates for all three enzymes (K-m similar to 10(-4) M). Absorption spectroscopy demonstrated such an interaction with the cofactor topaquinone, which is typical for common diamine substrates. However, only the former compound provided a regular reaction stoichiometry. Anaerobic absorption spectra of N-6-(3- aminopropyl) adenine, N-6-(4-amino-cis-but-2-enyl) adenine and N-6-(4-aminobut-2-ynyl) adenine reactions revealed a similar kind of initial interaction, although the compounds finally inhibited the enzymes. Kinetic measurements allowed the determination of both inhibition type and strength; N-6-(3-aminopropyl) adenine and N-6-(4-amino-cis-but-2-enyl) adenine produced reversible inhibition (K-i similar to 10(-5) - 10(-4) M) whereas, N-6-(4-aminobut-2-ynyl) adenine could be considered a powerful inactivator., DOI = 10.1080/14756360400021866, ISSN = 1475-6366, Unique-ID = ISI:000228805000006,
2004
- R. Buchtik, J. Hlavac, J. Slouka, and P. Frycak, “Cyclocondensation reaction of heterocyclic carbonyl compounds – 10. The
direction of competitive cyclocondensation between carbonyl groups of
6-azauracile and 1,2-dihydro-quinoxalin-2-one cycles.,” JOURNAL OF HETEROCYCLIC CHEMISTRY, vol. 41, iss. 4, pp. 597-599, 2004.
[Bibtex]@article ISI:000223479600019, Author = Buchtik, R and Hlavac, J and Slouka, J and Frycak, P, Title = Cyclocondensation reaction of heterocyclic carbonyl compounds - 10. The direction of competitive cyclocondensation between carbonyl groups of 6-azauracile and 1,2-dihydro-quinoxalin-2-one cycles., Journal = JOURNAL OF HETEROCYCLIC CHEMISTRY, Year = 2004, Volume = 41, Number = 4, Pages = 597-599, Month = JUL-AUG, Abstract = In the article the study of cyclocondensation of 3-[2-amino-3-(3,5-dioxo-2,3,4,5-tetrahydro[1,2,4]triazine-6-yl)pheny l]-2,3-dihydro-quinoxalin-2-one 5 is described and it was found, that the reaction does not proceed by both possible directions, but only cyclization with the carbonyl group of 6-azauracile cycle proceeds. The 6-(3-oxo-3,4-dihydro-quinoxaline-2-yl)-4H-2,3-dihydro[1,2,4]triazino[ 5,6-b]indol-3-one 6 was formed in this way. This course of cyclocondensation was confirmed by the fact, that the product 6, mentioned above, is quite different from isomeric compound 7, prepared unambiguously by condensation of 7-(6-azauracile-5-yl)isatine 8 with o-phenylenediamine., ISSN = 0022-152X, Unique-ID = ISI:000223479600019,
2003
- P. Frycak, K. Lemr, T. Adam, and R. Huskova, “Diagnostics of some inherited metabolic disorders by mass spectrometry
using modern ionisation techniques,” CHEMICKE LISTY, vol. 97, iss. 2, pp. 93-100, 2003.
[Bibtex]@article ISI:000181682000004, Author = Frycak, P and Lemr, K and Adam, T and Huskova, R, Title = Diagnostics of some inherited metabolic disorders by mass spectrometry using modern ionisation techniques, Journal = CHEMICKE LISTY, Year = 2003, Volume = 97, Number = 2, Pages = 93-100, Abstract = The review deals with the progress in the diagnostics of inherited metabolic disorders by mass spectrometry in the last decade. It is focused on the atmospheric pressure ionisation techniques, i.e. electrospray ionisation and atmospheric pressure chemical ionisation. The first part of the article describes very briefly the molecular causes of inherited metabolic disorders, such as disorders of metabolisms of fatty acids, amino acids, bile acids, purine and pyrimidine and related metabolites. The other part describes the procedures from sampling over the analysis itself to the raw data evaluation., ISSN = 0009-2770, Unique-ID = ISI:000181682000004,
2002
-
P. Frycak, R. Huskova, T. Adam, and K. Lemr, “Atmospheric pressure ionization mass spectrometry of purine and
pyrimidine markers of inherited metabolic disorders,” JOURNAL OF MASS SPECTROMETRY, vol. 37, iss. 12, pp. 1242-1248, 2002.
[Bibtex]@article ISI:000180149400009, Author = Frycak, P and Huskova, R and Adam, T and Lemr, K, Title = Atmospheric pressure ionization mass spectrometry of purine and pyrimidine markers of inherited metabolic disorders, Journal = JOURNAL OF MASS SPECTROMETRY, Year = 2002, Volume = 37, Number = 12, Pages = 1242-1248, Month = DEC, Note = 20th Meeting on Mass Spectrometry, FIERA DE PRIMIERO, ITALY, MAY 12-16, 2002, Abstract = Purines and pyrimidines are of interest owing to their significance in processes in living organisms. Mass spectrometry is a promising analytical tool utilized in their analysis. Two atmospheric pressure ionization (API) methods (electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI)) in both negative and positive modes applied to selected purine and pyrimidine metabolites (markers of inherited metabolic disorders) were studied. APCI is less sensitive to alkali metal cations present in a sample and offers higher response than ESI for studied compounds. Both of the techniques afford quasi-molecular ions, but fragmentation also occurs to a certain extent. However, the application of collision-induced dissociation of quasi-molecular ions is essential to confirm a certain metabolite in a sample. Fragmentation of both positive and negative ions was evaluated using multi-stage mass spectrometric experiments. Typical neutral losses correspond to molecules NH3, H2O, HCN, CO, H2NCN, HNCO and CO2. The ion [NCO](-) arises in the negative mode. The cleavage of the glycosidic C-N bond is characteristic for relevant metabolites. Other neutral losses (CH2O, C2H4O2 and C3H6O3) originate from fragmentation of the glycosidic part of the molecules. In addition to fragmentation, the formation of adducts of some ions with applied solvents (H2O, CH3OH) was observed. The composition of the solution infused into the ion source affects the appearance of the mass spectra. Tandem mass spectra allow one to distinguish compounds with the same molecular mass (uridine-pseudouridine and adenosine-2'-deoxyguanosine). Flow injection analysis APCI-MS/MS was tested on model samples of human urines corresponding to adenosine deaminase deficiency and xanthine oxidase deficiency. In both cases, the results showed potential diagnostic usefulness. Copyright (C) 2002 John Wiley Sons, Ltd., DOI = 10.1002/jms.389, ISSN = 1076-5174, Unique-ID = ISI:000180149400009,
2000
- K. Lemr, T. Adam, P. Frycak, and D. Friedecky, “Mass spectrometry for analysis of purine and pyrimidine compounds,” in PURINE AND PYRIMIDINE METABOLISM IN MAN X, 2000, pp. 399-403.
[Bibtex]@inproceedings ISI:000167131900076, Author = Lemr, K and Adam, T and Frycak, P and Friedecky, D, Editor = ZorefShani, E and Sperling, O, Title = Mass spectrometry for analysis of purine and pyrimidine compounds, Booktitle = PURINE AND PYRIMIDINE METABOLISM IN MAN X, Series = ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY, Year = 2000, Volume = 486, Pages = 399-403, Note = 10th International Symposium on Purine and Pyrimidine Metabolism in Man, TEL AVIV, ISRAEL, MAY 14-19, 2000, ISSN = 0065-2598, ISBN = 0-306-46515-9, Unique-ID = ISI:000167131900076,