2005). Therefore, the liquid wine samples were appropriately
diluted 50 times with deionized water, and then filtered by using
a 0.45 lm pore size filter. Chromatogram of several anions and
analytical results of the sulphite in wine samples are shown in
Fig. 5 and Table 1, respectively. According to Japanese Food Sanitation
Law, the residual amount of sulphite was prescribed to be the
value of sulphur dioxide, and therefore, the listed sulphite values
correspond to the sulphur dioxide value in the analysed wine
samples.
To confirm the reliability of this method, a recovery test was
performed for the wine sample spiked with sulphite at a certain
concentration. In the evaluation of the satisfactory recovery rate
and reproducibility of the analytical process, this method shows
applicability for the determination of sulphite in drinking water
without being affected by the coexisting ions.
4. Conclusion
In this study, suppressed ion chromatography with conductivity
detection was developed for the determination of sulphite in several
wines. When a mixed solution of 0.8 mM sodium carbonate,
6.0 mM sodium bicarbonate, and 5.0 (v/v)% acetone was used as
the mobile phase, sulphite was detected in approximately
12 min. The linearity of calibration curves, reproducibility of peak
height, and detection limits were determined for the proposed
method. Further, this method was applied for the determination
of sulphite in several wines, and it shows promise for the detection
of sulphite in drinking water in future studies.
Acknowledgement
This work was supported by Nihon University, College of Science
and Technology Grants-in-Aid for Fundamental Science