Naphthalenediols: A new class of novel fluorescent chemosensors for selective sensing of Cu2+ and Ni2+ in aqueous solution

Naphthalenediols(NDs) such as 1,5-naphthalenediol (1,5-ND) and 2,7-Naphthalenediol (2,7-ND) are found to be potent chemosensor for selective sensing of Cu2+ and Ni2+ ions respectively. The sensitivity and selectivity of chemosensors have been studied by incorporating NDs into β-Cyclodextrin (β-CD). The chemosensor behavior of NDs towards various transition metals is studied under selective pH medium. In 1,5-ND, the colorimetric chemosensor behavior has been identified and demonstrated in aqueous medium for the selective detection of Cu2+ without any modification, likewise 2,7-ND also having sensing ability towards Ni2+. The chemosensor probe 1,5-ND showed selective chromogenic behavior towards Cu2+ ions by changing the colour from pink to purple. No significant colour change is observed upon the addition of other metal ions. The sensing property of naphthalenediols towards metal cations has been studied using UV-vis and fluorescence spectral technique.