OXIDATION PATHWAYS OF NATURAL DYE HEMATOXYLIN IN AQUEOUS SOLUTION

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61388963%3A_____%2F10%3A00354402" target="_blank" >RIV/61388963:_____/10:00354402 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/61388955:_____/10:00354402

Výsledek na webu

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DOI - Digital Object Identifier

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Jazyk výsledku

angličtina

Název v původním jazyce

OXIDATION PATHWAYS OF NATURAL DYE HEMATOXYLIN IN AQUEOUS SOLUTION

Popis výsledku v původním jazyce

The oxidation mechanism of hematoxylin was studied in phosphate buffers and 0.1 M KCl by cyclic voltammetry and UV-Vis spectroscopy under deaerated conditions. The redox potential of hematoxylin in buffered solution strongly depends on pH. A two electronoxidation is preceded by deprotonation. The homogeneous rate of deprotonation process of hematoxylin in 0.1 M phosphate buffer is k(d) = (2.5 +/- 0.1) x 10(4) s(-1). The cyclic voltammetry under unbuffered conditions shows the distribution of various dissociation forms of hematoxylin. The dissociation constants pK(1) = 4.7 +/- 0.2 and pK(2) = 9.6 +/- 0.1 were determined using UV-Vis spectroscopy. The final oxidation product was identified by gas chromatography with mass spectrometry detection as hemathein. The distribution of oxidation products differs under buffered and unbuffered conditions. The dye degradation in natural unbuffered environment yields hemathein and hydroxyhematoxylin, which is absent in buffered solution.

Název v anglickém jazyce

OXIDATION PATHWAYS OF NATURAL DYE HEMATOXYLIN IN AQUEOUS SOLUTION

Popis výsledku anglicky

The oxidation mechanism of hematoxylin was studied in phosphate buffers and 0.1 M KCl by cyclic voltammetry and UV-Vis spectroscopy under deaerated conditions. The redox potential of hematoxylin in buffered solution strongly depends on pH. A two electronoxidation is preceded by deprotonation. The homogeneous rate of deprotonation process of hematoxylin in 0.1 M phosphate buffer is k(d) = (2.5 +/- 0.1) x 10(4) s(-1). The cyclic voltammetry under unbuffered conditions shows the distribution of various dissociation forms of hematoxylin. The dissociation constants pK(1) = 4.7 +/- 0.2 and pK(2) = 9.6 +/- 0.1 were determined using UV-Vis spectroscopy. The final oxidation product was identified by gas chromatography with mass spectrometry detection as hemathein. The distribution of oxidation products differs under buffered and unbuffered conditions. The dye degradation in natural unbuffered environment yields hemathein and hydroxyhematoxylin, which is absent in buffered solution.

Druh

J_x - Nezařazeno - Článek v odborném periodiku (Jimp, Jsc a Jost)

CEP obor

CG - Elektrochemie

OECD FORD obor

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Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

Z - Vyzkumny zamer (s odkazem do CEZ)

Rok uplatnění

2010

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Collection of Czechoslovak Chemical Communications

ISSN

0010-0765

e-ISSN

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Svazek periodika

75

Číslo periodika v rámci svazku

11

Stát vydavatele periodika

CZ - Česká republika

Počet stran výsledku

18

Strana od-do

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Kód UT WoS článku

000284230500003

EID výsledku v databázi Scopus

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