Jump to main content
Jump to site search


Green analytical flow method for the determination of total sulfite in wine using membraneless gas–liquid separation with contactless conductivity detection

Author affiliations

Abstract

A green analytical flow method was developed for the determination of total sulfite in white wine. The method employs the membraneless vaporization (MBL-VP) technique for gas–sample separation allowing direct analysis of wine. Sulfite in an aliquot of sample was converted to SO2 gas via acidification. Dissolution of the gas into the water acceptor led to a change in the conductivity of the acceptor which was monitored using a ‘capacitively coupled contactless conductivity detector’ (C4D) flow cell. Only a minute amount of common acid (100 μL of 1.5 mol L−1 H2SO4) is used. The MBL-VP unit was incorporated into the flow system to separate the SO2 gas from the wine sample using the headspace above the donor and acceptor compartments as a virtual membrane. The method provides a linear working range (10–200 mg L−1 sulfite) which is suitable for most wines with calibration equation y = (0.056 ± 0.002)x + (1.10 ± 0.22) and r2 = 0.998. Sample throughput is 26 samples h−1. The lower limit of quantitation (LLOQ = 3SD of blank per slope) is 0.3 mg L−1 sulfite for 20 s diffusion time with good precision (%RSD = 0.8 for 100 mg L−1 sulfite, n = 10). We also present a simple modification of the MBL-VP unit by the addition of a third cone-shaped reservoir to provide two acceptor zones leading to improvement in sensitivity of more than three-fold without use of heating to enhance the rate of diffusion of SO2.

Graphical abstract: Green analytical flow method for the determination of total sulfite in wine using membraneless gas–liquid separation with contactless conductivity detection

Back to tab navigation

Supplementary files

Publication details

The article was received on 01 Aug 2017, accepted on 22 Sep 2017 and first published on 22 Sep 2017


Article type: Paper
DOI: 10.1039/C7AY01879G
Citation: Anal. Methods, 2017, Advance Article
  •   Request permissions

    Green analytical flow method for the determination of total sulfite in wine using membraneless gas–liquid separation with contactless conductivity detection

    N. Chantipmanee, W. Alahmad, T. Sonsa-ard, K. Uraisin, N. Ratanawimarnwong, T. Mantim and D. Nacapricha, Anal. Methods, 2017, Advance Article , DOI: 10.1039/C7AY01879G

Search articles by author

Spotlight

Advertisements