Synthesis and Characterization of a New Red-Emitting Ca~(~(2+)) Indicator, Calcium Ruby

摘要

Calcium Ruby m-Cl (X = H, Y = Cl) is a visible-light excited red-emitting calcium concentration ([Ca~(2+)]) indicator dye (579/598 nm peak excitation/emission) with a side arm for conjugation via EDC or click chemistry. Its large molar extinction and high quantum yield rank it among the brightest long-wavelength Ca~(2+) indicators. Calcium Ruby is a promising alternative to existing dyes for imaging [Ca~(2+)] in multicolor fluorescence applications or in the presence of yellow-green cellular autofluorescence.