Detection of environmental pollutants heavy metal ions based on the complexation with fluorescent dyes: Reaction of 2-(2ʹ-hydroxyphenyl)-5-amino-benzotriazole with the Sn2+, Hg2+, and Pb2+ ions

[Display omitted] •A fluorescent hydroxyphenylbenzotriazole derivative was synthesized.•The dye was complexed with Sn2+, Hg2+, and Pb2+ metal ions.•Considerable spectral shifts were observed after complexation.•These shifts can be used to differentiate Sn2+ complex from other complexes. Providing a clean environment free of pollutants, toxic substances, and hazardous materials is a pressing worldwide concern. Fluorescent dyes are a promising means to achieve this goal, and their application extends to medicine, academia, and industry. This work aims to provide basic data on a dye that can be used for the detection, quantification, and extraction of heavy metal ions based on its complexation with these environmental pollutants. A hydroxyphenylbenzotriazole derivative, 2-(2ʹ-hydroxyphenyl)-5-amino-benzotriazole (LH), was synthesized, characterized, and chelated with Sn2+, Hg2+, and Pb2+ metal ions. The synthesized LH dye and its metal complexes were characterized using a range of physicochemical and spectroscopic techniques. Binding the dye to the investigated metal ions resulted in colored complexes with 1:2 (metal: dye) stoichiometry and the general composition of [ML2]·xH2O. Larger spectral shifts were observed in the absorption and emission spectra of dye molecule after complexation with the Sn2+ ion compared with the other two metal ions.