Electrochemical Study and Determination of All-trans Retinol at Carbon Paste Electrode Modified by Surfactant

• Published in: Food technology and biotechnology Vol. 56; no. 3; pp. 337 - 343
• Main Authors: Žabčíková, Simona, Mikysek, Tomáš, Červenka, Libor, Sýs, Milan
• Format: Journal Article
• Language: English
• Published: Croatia Sveuciliste U Zagrebu 01.09.2018; Sveuciliste u Zagrebu, Prehramheno-Biotehnoloski Fakultet; University of Zagreb Faculty of Food Technology and Biotechnology
• Subjects: all-trans-retinol, surfactant; Anionic surfactants; Bonds (Securities); Carbon; Carbon electrodes; Chemical properties; Chemical research; Chromatography; Detection limits; Differential media; differential pulse voltammetry; Electroanalysis; Electrochemistry; Electrodes; Electrolytes; Electrolytic analysis; Electrons; Esters; Food; Glassy carbon; glassy carbon electrode; modified carbon paste electrode; Original Scientific Papers; Oxidation; Oxidation-reduction reactions; Particle size; Poisoning; Retinoids; Silver chloride; Sodium; Sodium dodecyl sulfate; Sodium lauryl sulfate; Sulfates; Surface active agents; Surfactants; Vitamin A; Vitamin deficiency; Vitamin E; Vitamins; Voltammetry; United States > US; Czech Republic; all-trans-retinol; glassy carbon electrode; differential pulse voltammetry; modified carbon paste electrode; surfactant
• ISSN: 1330-9862; 1334-2606
• DOI: 10.17113/ftb.56.03.18.5618

The oxidation mechanism of all- -retinol (vitamin A ) and its several esters in non-aqueous, aqueous organic mixture, and pure aqueous media was investigated by cyclic voltammetry. The oxidation occurred in several irreversible steps. The calculated highest density of electrons in retinoid molecules which are delocalized over carbon atoms of the five conjugated double bonds (C5-C14) was found in the part of the molecule involved in oxidation processes. The most sensitive oxidation peak (at +0.8 V . Ag/AgCl) was used for development of new direct voltammetric method based on differential pulse voltammetry for the determination of retinol at carbon paste electrode modified with surfactant sodium dodecyl sulfate (CPE/SDS). The results show that 30% (by mass) of modifier SDS exhibited optimal sensitivity and shape of voltammograms. Compared to commonly used glassy carbon electrode (GCE), the CPE/SDS showed significant progress in the retinol electroanalysis. The linear ranges for retinol determination were 1.5·10 -1.8·10 M for CPE/SDS and 4.4·10 -7.0·10 M for GCE with the detection limits of 1.3·10 and 4.6·10 M, respectively.