Fluorescence imaging of intracellular cadmium using a dual-excitation ratiometric chemosensor.
We described here a coumarin-based dual-excitation ratiometric probe for cadmium, CadMQ. This fluorescence sensor has high quantum yields of 0.59 and 0.70 in the metal-free and Cd2+-bound forms, respectively, and has a dissociation constant of 0.16 nM for Cd2+. CadMQ is cell permeable and locates within the acidic compartments of the cells. We further show that CadMQ is a useful tool to ratiometrically probe the change in the intracellular Cd2+ levels with the use of two excited wavelengths.
Taki
Masayasu
M
Graduate School of Human and Environmental Studies, Kyoto University, Yoshida, Sakyo-ku, Kyoto 606-8501, Japan. taki@chem.mbox.media.kyoto-u.ac.jp
Desaki
Mika
M
Ojida
Akio
A
Iyoshi
Shohei
S
Hirayama
Tasuku
T
Hamachi
Itaru
I
Yamamoto
Yukio
Y