Petr Fryčák

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,