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Badanie własności związków kompleksowych wybranych biopierwiastków ze składnikami napojów energetyzujących

Giełzak-Koćwin K., Poroś P.

Chemistry, Environment, Biotechnology

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2017

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Vol. 20

43--50

PL

Napoje energetyzujące cieszą się w Polsce znaczną popularnością, zwłaszcza wśród studentów podczas wzmożonej pracy umysłowej czy sportowców intensywnie trenujących. Produkty te mogą mieć zarówno pozytywne, jak i negatywne oddziaływanie, stąd konieczność prowadzenia badań nad ich optymalnym składem i działaniem na organizm. W tej publikacji badano zdolności kompleksowania wybranych składników napojów energetyzujących, tauryny i L-karnityny z jonami metali bioaktywnych, miedzi(II) i oksowanadu(IV). Przeprowadzono pomiary spektrofotometryczne w zakresie widzialnym promieniowania elektromagnetycznego dla roztworów wodnych zawierających różne stężenia jonów metali oraz tauryny i L-karnityny oraz pomiary pH-metryczne roztworów. Wykazano możliwości tworzenia trwałych połączeń koordynacyjnych L-karnityny z Cu2+ i VO2+ oraz bardzo słabe oddziaływania z tauryną. Wprowadzenie słabej zasady (amoniaku) i słabego kwasu (kwasu octowego), zmieniających pH roztworów badanych, miało zasadniczy wpływ na stany równowagowe w roztworach kompleksów z tauryną i L-karnityną.

EN

Energy drinks sustain considerable level of popularity in Poland, especially among students doing intense mental work or intensively training sportsmen. These products can have both positive and negative influence, hence the need to conduct research on their optimal composition and effects on the body. In this paper the complexation abilities of selected components of energy drinks, taurine and L-carnitine with bioactive metal ions, copper(II) and oxovanadium(IV) have been tested. Spectrophotometric measurements were made in aqueous solutions containing varying amounts of metals and taurine or L-carnitine, without any buffer solutions, and without stabilization of ionic strength in the visible range of electromagnetic radiation as well as the solutions pH-metric measurements. The ability to create persistent coordination bonds of L-carnitine with Cu2+ and VO2+ has been shown as well as a very weak interactions with taurine. Addition of components altering pH of the solutions had a major effect on the equilibrium states in the solution of ammonia and of acetic acid complexes with taurine and L-carnitine.

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Synthesis and Structural Studies on Oxovanadium(IV) Complexes with Polyaza Macrocyclic Ligands Derived from 1,4-Phenylenediamine, Formaldehyde and Primary Diamines

Pandey J., Pandey O., Sengupta S.

Polish Journal of Chemistry

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2006

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Vol. 80, nr 12

1983-1989

EN

A new series of N4 donor macrocyclic oxovanadium(IV) complexes of type [VO(mac)]SO4 (mac =macrocyclic ligands derived from 1,4-phenylenediamine, formaldehyde and various primary diamines) have been prepared by template method. Tentative structures of the complexes have been proposed on the basis of elemental analyses, electrical conductance, magnetic moment and spectral (IR, electronic and EPR) data. The X-band EPR spectra of all the complexes have been recorded at room temperature and at liquid nitrogen temperature. The room temperature EPR spectra do not show anisotropy because of rapid tumbling of molecules in solution. The spectral studies support square-pyramidal geometry for the oxovanadium(IV) complexes.

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Synthesis, Spectral and Antiferromagnetic Interaction in Oxalato-Bridged Linear TRinuclear Oxovanadium(IV) Complexes

Li Y., Yan C., Guan H.

Polish Journal of Chemistry

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2004

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Vol. 78 / nr 2

187-194

EN

Three new linear trinuclear oxovanadium(IV) complexes bridged by oxalato (ox) and end-capped with 2,2_-bipyridine (bpy); 1,10-phenanthroline (phen) or 5-nitro-1,10- phenanthroline (NO2phen); respectively, namely [(VO)3(ox)2(bpy)2]SO4 (1), [(VO)3(ox)2(phen)2]SO4 (2) and [(VO)3(ox)2(NO2phen)2]SO4 (3), have been synthesized and characterized by elemental analyses, molar conductivity, magnetic measurements, IR, ESR and electronic spectral studies. It is proposed that these complexes have extended ox-bridged structures, consisting of three oxovanadium(IV) ions, each in a distorted square-pyramidal environment. Variable-temperature magnetic susceptibility measurements (4.2~300 K) of the complexes (1) and (2) revealed the occurrence of an intramolecular antiferromagnetic interaction between the oxovanadium(IV) ions through the oxalato-bridge within each molecule. The magnetic data have been also used to deduce the indicated structure. On the basis of spin Hamiltonian operator, _ _ _ H = 2J(S S S_ S_ ) 1 2 2 3 Ĺ + Ĺ , the magnetic analyses were carried out for the two trinuclear complexes and the spin-coupling constants (J) were evaluated as -9.85 cm-1 for (1) and -10.16 cm-1 for (2).

4

Synthesis and Magnetic Properties of Dinuclear Oxovanadium(IV) Complexes Bridged by Tetracarboxylato Groups

Li Y., Yan C., Guan H.

Polish Journal of Chemistry

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2004

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Vol. 78 / nr 1

1-7

EN

Three novel _-tetracarboxylato-bridged oxovanadium(IV) dinuclear complexes described by the overall formula [(VO)2(PMTA)L2], where PMTAstands for the tetraanion of pyromellitic acid, and L denotes 2,2_-bipyridine (bpy), 4,4_-dimethyl-2,2_-bipyridine (Me2bpy) or 1,10-phenanthroline (phen), respectively, have been synthesized and characterized by elemental analyses, molar conductivity and room-temperature magnetic moment measurements, IR, ESR and electronic spectral studies. It is proposed that these complexes have PMTA-bridged structures and consist of two oxovanadium(IV) ions, each in a square-pyramidal environment. The [(VO)2(PMTA)(bpy)2] (1) and [(VO)2(PMTA)(phen)2] (2) complexes were further characterized by variable temperature (4.2~300 K) magnetic susceptibility measurements and the observed data were fitted to the modified Bleaney-Bowers equation by the least-squares method, giving the exchange integral J = -2.75 cm-1 for (1) and J = -3.91 cm-1 for (2). This result indicates that there is a weak antiferromagnetic spin-exchange interaction between the two VO2+ ions within each molecule.

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Synthesis and Magnetic Studies of M-Iodanilato-Bridged Binuclear Oxovanadium(IV) Complexes

Li Y., Yan C.

Polish Journal of Chemistry

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2000

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Vol. 74, nr 8

1071-1077

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Oxovanadium(IV) complexes of 1-hydroxyalkane-1,1-diyldiphosphonic acids

Dyba M., Kozłowski H., Tlałka A., Leroux Y., El Manouni D.

Polish Journal of Chemistry

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1998

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Vol. 72, nr 7

1148-1153

EN

Potentiometric and spectroscopic (EPR and UV-VIS) methods were used to study the oxovanadium(IV) complexation with several 1-hydroxyalkane-1,1-diyldiphosphonic acids. Coordination of oxovanadium(IV) to all diphosphonic ligands studied starts at very low pH and formation of the stable monomeric and trinuclear species between pH range 2-9 is observed.