The reduction of sulfite in acidic medium was found to lead to the production of a radical anion that provides a versatile, sensitive and readily accessible diagnostic alternative to current electrochemical detection methodologies.
Isaac, A., Wain, AJ., Compton, RG., Livingstone, C., & Davis, J. (2005). A novel electroreduction strategy for the determination of sulfite. ANALYST, 130(10), 1343-1344. https://doi.org/10.1039/b509721e