Item

Speciation study of aluminium in beverages by Competitive Ligand Exchange-Adsorptive Stripping Voltammetry

Magnier, A.
Fekete, V.
Bolle, F.
Elskens, M.
Citations
Altmetric:
Abstract

Competitive Ligand Exchange-Adsorptive Stripping Voltammetry (CLE-AdSV) was used for determining the speciation of aluminium in commonly consumed beverages (water, tea, infusion, coffee, orange juice, tomato juice, beer and red wine). Aluminium determination involves the adsorption of Al-complexes with the ligand cupferron onto a hanging mercury drop electrode. All samples were studied at pH 6.5 with an accumulation step at -0.60 V (all potential values in the paper are given versus the Ag/AgCl, [KCl]=3 M reference electrode) during 60 s, and a final cupferron concentration of 4×10-4 M. These conditions were used to establish (i) the concentration of electro-labile aluminium, (ii) the range of ligand concentrations and (iii) the conditional stability constants of beverage samples using titration procedures. The results based on Ruzic plots were compared to computer simulation with Visual MINTEQ. This comparison suggests that labile monomeric Al-forms and soluble organic complexes of low molecular weight can be quantified by the CLE-AdSV procedure. Overall the relative uncertainties on the determination of the electro-active Al fraction and the complexing parameters, i.e., concentration and conditional stability constant of natural ligands in the samples, are less than 15%. Thanks to these results, information on Al bioavailability in beverages was collected and discussed. This study also illustrates the value of computer simulations when complex, time-consuming voltammetric techniques are applied.

Description
Date
2014-05-15
Journal Title
Journal ISSN
Volume Title
Publisher
Chapter title
Publication type
Peer reviewed scientific article
Research Projects
Organizational Units
Journal Issue
Keywords
ALL, Aluminium, at, beer, Beverages, CLE; G; ÇôAdSV, Comparison, conditions, Cupferron, Fraction, i, INFORMATION, Less, Ligands, M, mercury, Molecular Weight, organic, Paper, parameters, ph, RANGE, RED, relative, result, results, S, Sample, Samples, Speciation, stability, study, Tea, Technique, Tomato, uncertainty, values, WATER, Weight, Wine
Citation
Topic(s)
Related project
Embedded videos