Jump to main content
Jump to site search
PLANNED MAINTENANCE Close the message box

Scheduled maintenance work on Wednesday 27th March 2019 from 11:00 AM to 1:00 PM (GMT).

During this time our website performance may be temporarily affected. We apologise for any inconvenience this might cause and thank you for your patience.


Issue 17, 2016
Previous Article Next Article

OFF–ON–OFF fluorescent response of N,N,N′,N′-tetrakis(1-isoquinolylmethyl)-2-hydroxy-1,3-propanediamine (1-isoHTQHPN) toward Zn2+

Author affiliations

Abstract

An isoquinoline-based ligand, N,N,N′,N′-tetrakis(1-isoquinolylmethyl)-2-hydroxy-1,3-propanediamine (1-isoHTQHPN), exhibits a fluorescence increase at 475 nm upon addition of 1 equiv. of Zn2+ (IZn/I0 = 12, ϕZn = 0.023). This fluorescence enhancement turns and then decreases sharply after the addition of more than 1 equiv. of Zn2+ reaching a constant minimum intensity with more than 2 equiv. of Zn2+. In contrast, the fluorescence intensity at 353 nm continues to increase until the signal saturates at ca. 5 equiv. of Zn2+. This observation can be explained by the formation of a fluorescent mononuclear complex ([Zn(1-isoHTQHPN)]2+) followed by a non-fluorescent dinuclear complex ([Zn2(1-isoTQHPN)]3+) at 475 nm during the titration of 1-isoHTQHPN with Zn2+. Both the mono- and dinuclear complexes were characterized by UV-vis, fluorescence, 1H NMR, ESI-MS, X-ray crystallography and TDDFT calculations. The fluorescence enhancement at 475 nm is Zn2+-specific; Cd2+ induces a much smaller emission increase (ICd/I0 = 3.7, ICd/IZn = 31%). The Zn2+/Cd2+ selectivity of the fluorescent response correlates with the difference in excimer-forming ability derived from the Cd–Nisoquinoline and Zn–Nisoquinoline bond distances.

Graphical abstract: OFF–ON–OFF fluorescent response of N,N,N′,N′-tetrakis(1-isoquinolylmethyl)-2-hydroxy-1,3-propanediamine (1-isoHTQHPN) toward Zn2+

Back to tab navigation

Supplementary files

Publication details

The article was received on 04 Feb 2016, accepted on 09 Mar 2016 and first published on 09 Mar 2016


Article type: Paper
DOI: 10.1039/C6DT00506C
Citation: Dalton Trans., 2016,45, 7250-7257

  •   Request permissions

    OFF–ON–OFF fluorescent response of N,N,N′,N′-tetrakis(1-isoquinolylmethyl)-2-hydroxy-1,3-propanediamine (1-isoHTQHPN) toward Zn2+

    Y. Mikata, R. Ohnishi, A. Ugai, H. Konno, Y. Nakata, I. Hamagami and S. Sato, Dalton Trans., 2016, 45, 7250
    DOI: 10.1039/C6DT00506C

Search articles by author

Spotlight

Advertisements