Affordable Access

Publisher Website

Convenient, inexpensive quantification of elemental sulfur by simultaneousin situreduction and colorimetric detection

Authors
Journal
Analytica Chimica Acta
0003-2670
Publisher
Elsevier
Publication Date
Volume
703
Issue
1
Identifiers
DOI: 10.1016/j.aca.2011.07.010
Keywords
  • Wine
  • Grapes
  • S8
  • Pesticide Residue

Abstract

Abstract Rapid, inexpensive, and convenient methods for quantifying elemental sulfur (S 0) with low or sub-μg g −1 limits of detection would be useful for a range of applications where S 0 can act as a precursor for noxious off-aromas, e.g., S 0 in pesticide residues on winegrapes or as a contaminant in drywall. However, existing quantification methods rely on toxic reagents, expensive and cumbersome equipment, or demonstrate poor selectivity. We have developed and optimized an inexpensive, rapid method (∼15 min per sample) for quantifying S 0 in complex matrices. Following dispersion of the sample in PEG-400 and buffering, S 0 is quantitatively reduced to H 2S in situ by dithiothreitol and simultaneously quantified by commercially available colorimetric H 2S detection tubes. By employing multiple tubes, the method demonstrated linearity from 0.03 to 100 μg S 0 g −1 for a 5 g sample ( R 2 = 0.994, mean CV = 6.4%), and the methodological detection limit was 0.01 μg S 0 g −1. Interferences from sulfite or sulfate were not observed. Mean recovery of an S 0 containing sulfur fungicide in grape macerate was 84.7% with a mean CV of 10.4%. Mean recovery of S 0 in a colloidal sulfur preparation from a drywall matrix was 106.6% with a mean CV of 6.9%. Comparable methodological detection limits, sensitivity, and recoveries were achieved in grape juice, grape macerate and with 1 g drywall samples, indicating that the methodology should be robust across a range of complex matrices.

There are no comments yet on this publication. Be the first to share your thoughts.