Determination of lead in wines by hydride generation atomic absorption spectrometry

Abstract

The optimization of lead hydride generation in aqueous ethanolic media and the influence on its generation of the wine components, both white and red, have been studied. These interferences were overcome by careful control of the parameters affecting hydride generation and the procedure was applied to the determination of Pb in wines. The method is fast, accurate and sensitive and can be used to quantify 24 ppb of Pb in wines.

Determination of lead in wine and rum samples by flow injection-hydride generation-atomic absorption spectrometry

“…No significant effects were observed from ethanol (up to almost 100%), potassium tartrate (up to 1%, m/v) and dextrose (up to 5%, m/v) on the generation of lead hydride and consequently the absorbance. The results for ethanol were different from that reported by Cacho et al [25], who observed interference from ethanol using H 2 O 2 as oxidizing agent in analysis of wine samples for lead. This was probably due to the differences in the performance of the oxidizing agents, K 3 Fe(CN) 6 and H 2 O 2 , used to convert P(II) to Pb(IV).…”

“…The reduction in the signal profile was similar to that observed with HCl concentration greater than 0.4% (v/v). When compared with potassium tartrate, the suppression or decrease in hydride generation efficiency with tartaric acid was attributed to the increased acidity of the sample solution as also reported in a previous work [25].…”

“…This was probably due to the differences in the performance of the oxidizing agents, K 3 Fe(CN) 6 and H 2 O 2 , used to convert P(II) to Pb(IV). Flame fuel/air ratio may have also contributed to the interference from ethanol reported by Cacho et al [25], as it necessitates a highly oxidizing flame to overcome the high background. In the presence of tartaric acid, the peak height absorbance of Pb reduced due to the tartaric acid concentration exceeded 0.4% (m/v) in the sample solution.…”

“…There are few studies of lead hydride generation in wines those that include the batch mode generation of lead hydride with or without mineralization of the samples [9,[25][26][27][28][29].…”

A Simple and Sensitive Flow-Injection On-line Preconcentration Coupled with Hydride Generation Atomic Fluorescence Spectrometry for the Determination of Ultra-trace Lead in Water, Wine, and Rice

“…1,[19][20][21] However, for wine samples' analysis, ethanol matrix markedly suppresses the efficiency of lead hydride generation, 22 which calls for the development of simple on-line preconcentration and separation procedures. To date, such work dealing with the combination of flow injection/sequential injection on-line preconcentration and separation with hydride generation atomic fluorescence spectrometry (HG-AFS) is rare, 2 due to the narrow range of acidity required for the generation of lead hydride.…”