Design and synthesis of a squaraine based near-infrared fluorescent probe for the ratiometric detection of Zn2+ ions

• Published in: Dyes and pigments Vol. 99; no. 3; pp. 699 - 704
• Main Authors: Huang, Yangwei, Lin, Qian, Wu, Jiaming, Fu, Nanyan
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.12.2013
• Subjects: Acetone; Binding; Bipyridyl ionophore; Dyes; Fluorescence; Fluorescent sensor; Mathematical analysis; Near-infrared functional dye; Pigments; Ratiometric detection; Squaraine; Synthesis; Zinc ion; Fluorescent sensor; Ratiometric detection; Near-infrared functional dye; Bipyridyl ionophore; Zinc ion; Squaraine
• ISSN: 0143-7208; 1873-3743
• DOI: 10.1016/j.dyepig.2013.06.020

A squaraine based ratiometric near-infrared fluorescent probe with bipyridyl binding arms for Zn2+ (SQ-1) has been designed and synthesized. SQ-1 exhibits a selective fluorogenic response to Zn2+ in acetone by a 22 nm red-shift and a remarkable enhancement of the fluorescence intensity. Further study shows that the calculated detection limit for Zn2+ is 6.1 × 10−8 M (3σ/k) and the identification for Zn2+ will not be impacted by competing ions such as Na+, K+, Mg2+, Ca2+, Pb2+, Mn2+, Ba2+ and Hg2+. The binding mode between SQ-1 and Zn2+ has also been discussed. [Display omitted] •A novel ratiometric near-infrared fluorescent probe (SQ-1) for Zn2+ has been first synthesized based on squaraine dye.•SQ-1 can detect Zn2+ in acetone by a 22 nm red-shift and a remarkable enhancement of the fluorescence intensity.•The detection identification for Zn2+ will not be impacted by the biologically ubiquitous ions such as Na+, K+, Mg2+ and Ca2+.