A new Hg2+-selective fluorescent sensor based on a dansyl amide-armed calix[4]-aza-crown

A new fluorescent chemosensor for Hg2+ based on a dansyl amide-armed calix[4]-aza-crown was reported. It exhibits high sensitivity and selectivity toward Hg2+ over a wide range of metal ions in MeCN–H2O (4:1, v/v). The association constant of the 1:1 complex formation for 2-Hg2+ was calculated to be 1.31 × 105 M−1, and the detection limit for Hg2+ was found to be 4.1 × 10−6 mol L−1.