Naked-eye and selective detection of mercury (II) ions in mixed aqueous media using a cellulose-based support

A test paper for high-selectivity detecting Hg2+ ions in mixed acetonitrile-water solutions has been achieved using a bis( ferrocenyl) azine, as chromogenic chemosensor molecule, and a solid cellulose fibre, as a substrate. Depending on the amount of mercury ions in contact with the detecting molecule a spectacular color change in the cellulose indicator is produced, being possible to determine the concentration of Hg2+ ions either by naked eye or spectroscopically.