A simple and highly selective 1,2,4,5-tetrazine-based colorimetric probe for HSO ion recognition in food.

A series of 3,6-bis-substituted-1,2,4,5-tetrazine-based colorimetric probes has been developed in good yields that exhibits highly selective and sensitive colorimetric recognition of HSO in aqueous solution. The color of the solution containing colorimetric probes changed markedly from orange to colorless, upon the addition of HSO . Quantification of the absorption titration analysis shows that the detection limit of 3,6-bis(2-aminoethylamino)-1,2,4,5-tetrazine (2a) for HSO was 3.