Table 19.6 Fluorescent indicators for Zn2+.

Indicator Water-Soluble Salt Cell-Permeant Ester Ex/Em * Kd for Zn2+ †
FluoZin-1F24180F24181495/5158 µM
FluoZin-2NAF24189495/5252 µM
FluoZin-3F24194F24195494/51615 nM **
RhodZin-3R36350R36351550/57565 nM
Newport Green DCFN7990N7991505/5351 µM
Newport Green PDXNAN24191495/52030 µM
* Excitation (Ex) and Emission (Em) maxima, in nm. † Dissociation constant of the indicator Zn2+ complex measured in 50 mM MOPS, pH 7.0, at 22°C. ‡ Excitation peak shifts upon binding Zn2+. § Emission peak shifts upon binding Zn2+. ** Kd determined in 135 mM NaCl, 1.1 mM EGTA, 20 mM HEPES, pH 7.4, 0–10 µM free Zn2+ at 22°C. NA = Not available.